Biofouling protection

Abstract

Disclosed are methods for protecting articles and / or structures exposed, submerged and / or partially submerged in aquatic environments from contamination and / or fouling due to invasion and / or colonization of biological organisms and / or plants of particular types and / or species (e.g., biological organisms and / or plants). Devices, methods and / or systems including protection against microscopic and / or macroscopic fouling over an extended period of time of exposure to an aquatic environment).

Description

[0001] This invention is a divisional application of the invention patent with application number 2020800283555, application date March 13, 2020, and invention name “Biofouling Protection”.

[0002] CROSS-REFERENCE TO RELATED APPLICATIONS

[0003] This application claims priority to and the benefit of U.S. Provisional Patent Application No. 62 / 817,873, filed on March 13, 2019, and entitled “BIOFOULING PROTECTIVE ENCLOSURES,” and Patent Cooperation Treaty (PCT) Patent Application No. PCT / US19 / 59546, filed on November 1, 2019, and entitled “DURABLE BIOFOULING PROTECTION,” the disclosures of each of which are incorporated herein by reference in their entirety. Technical Field

[0004] The present invention relates to improved devices, methods and / or systems for protecting articles and / or structures exposed to, immersed in and / or partially immersed in an aquatic environment from fouling and / or fouling due to invasion and / or colonization by specific types and / or species of biological organisms. More specifically, improved methods, apparatus and / or systems for protecting structures and / or substrates from microscopic and / or macroscopic fouling during extended periods of exposure to an aquatic environment are disclosed. Background Art

[0005] The growth and attachment of various marine organisms to structures in aquatic environments, known as biofouling, is a significant problem for many industries, including recreational and industrial boating and shipping, the oil and gas industry, power plants, water treatment plants, water management and control, irrigation industries, manufacturing, scientific research, the military (including the Corps of Engineers), and the fishing industry. Most surfaces exposed to coastal, harbor, or seawater (and its freshwater counterpart), such as those associated with ship hulls, underwater moorings, chains and piles, oil rig platforms, buoys, boom systems, fishing nets, piers, and docks, are eventually colonized by animal species, such as barnacles, mussels (as well as oysters and other bivalves), bryozoans, hydrozoans, polychaetes, ascidians, and / or other tunicates, as well as various plant species. Biofouling is caused by the interaction between various plant species and / or animal species and various aspects of the substrate to which the plant species and / or animal species ultimately attach, resulting in the formation of an adhesive that firmly binds the biofouling organisms to the substrate, thereby causing biofouling. Despite its apparent simplicity, the biofouling process is a highly complex network of interactions influenced by a myriad of microorganisms, macroorganisms, and changing characteristics of the aquatic environment.

[0006] The economic impact of biofouling is critical to many industries. Extensive biofouling on vessels can lead to corrosion of various surfaces exposed to the aquatic environment, greatly reducing the efficiency of vessel operations and often ultimately leading to the degradation of various parts of the vessel. The accumulation of micro- and macro-organisms can also lead to an increase in the roughness of the vessel's surface, causing the vessel to experience greater frictional resistance, reduced speed and maneuverability, and increased drag, resulting in increased fuel consumption. Both commercial and recreational boaters experience these increased costs due to the attachment of barnacles and other animals to submerged propellers, drive system components, inlets and / or hull components.

[0007] Another important economic consequence of biofouling is the formation of biofouling and / or scaling-induced scale on heat exchange surfaces and / or other wetted surfaces in many industrial facilities. For example, large-scale cooling water systems are used in a variety of industrial processes, and these systems rely most fundamentally on heat transfer from a hotter fluid or gas to a cooler fluid or gas, where this heat typically travels through a "heat transfer surface," which is typically a metal wall of a heat transfer tube that separates the cold and hot substances. Typically, the cooling fluid will include water, which in many cases can be salt water drawn from a bay, sea, and / or ocean, fresh water drawn from a river, lake, or well / aquifer, or wastewater from a variety of sources. Water is a favorable environment for many life forms, and these fouling organisms typically colonize the wetted surfaces of the heat transfer tubes, which can significantly reduce the heat transfer rate of the cooling system. In many cases, even a thin biofilm formed on a heat transfer surface can significantly isolate this surface, reducing its heat transfer efficiency and greatly increasing the overall operating cost of the cooling system.

[0008] In addition to increasing corrosion and other damage to structures, the weight and distribution of macro-fouling on an object can also significantly change the buoyancy or stress and strain experienced by the object and / or supporting structure, which can lead to premature damage and / or sinking of the fouled object. For example, a navigation buoy, oil boom, or pier pillar with a large amount of biofouling on the surface will experience increased stress loads due to the increased weight, and may even sink or sink under excessive macro-fouling. This increased stress often leads to a reduction in the useful life of the structure and requires continuous cleaning and / or replacement. Similarly, due to the invasion and / or colonization of marine organisms, submerged sensors (including tethered sensors and / or free-floating sensors) often fail and / or malfunction relatively quickly (often in less than 30 days).

[0009] Biofouling also creates significant ecological problems by distributing plant and animal species to non-native environments as they "ride along" the fouled objects, and significant legislative and financial resources have been allocated to combat the commercial and ecological impacts of biofouling.

[0010] Various methods have been used to attempt to prevent and / or reduce biofouling buildup. One of the more common methods, particularly in the shipping and maritime industries, is to remove biofouling by scraping. However, scraping is labor intensive and can damage the fouled surface, and has caused environmental concerns due to scraping resulting in increased spread of invasive species and negative environmental impacts on local fauna. Therefore, there is a need for devices that eliminate or reduce the amount of biofouling on surfaces exposed to aquatic environments.

[0011] One strategy for protecting objects in contact with water and preventing fouling by aquatic organisms involves the use of physical covers. These covers desirably act as protective devices by shielding structures from the effects of water or isolating structures from water. For example, U.S. Pat. No. 3,220,374 discloses a marine protective device. The present invention relates to a unique means and method for protecting marine equipment from the corrosive effects of water and / or the growth of marine organisms when the vessel is not in use.

[0012] U.S. Patent No. 3,587,508 discloses an outboard motor protective device that is easily attached to a boat. The device protects the outboard motor of an inboard outboard engine from marine growth when the boat is not in use. The bag is placed around the outboard motor unit so as to be easily attached to the transom in a manner that provides a watertight seal between the bag and the transom of the boat and around the outboard motor unit.

[0013] U.S. Patent No. 4,998,496 discloses a shield for a marine propulsion system, the shield comprising a waterproof shield body that can be fastened to the transom of a vessel to surround an outboard portion of the propulsion system. A locking and sealing mechanism secures the shield to the transom of the vessel in a watertight engagement, and a submersible pump is operable to remove water from the shield body so that the propulsion system is effectively in a "dry dock" when not in use.

[0014] U.S. Patent No. 5,072,683 discloses a drainable protective boat motor bag apparatus including a protective cover defining a bag over the bow and propeller of an outboard motor mounted on the stern of a boat. The bag includes a passage extending from the mouth to the closed end of the bag for receiving an open-ended hose so that once the bag is positioned over the bow, the hose can be inserted to suction residue from such bag. A tether may be incorporated around the mouth of the bag to tie it to the bow, and if desired, a separate protective bag may be included for covering the propeller blades to protect the propeller blades from direct exposure to the bag itself.

[0015] U.S. Patent No. 5,315,949 discloses a device for protectively covering a motor support of a boat. The cover includes an adjustable collar, an opaque flexible bag, and an adjustable collar pull line. The bag has an open top end attached to the collar. The closed bottom end of the bag is opposite to the top end and has a weight attached thereto. The adjustable collar pull line of the collar allows the open end of the bag to be closed around the exposed object by pulling the adjustable collar pull line when the bag is placed above the exposed object. The collar includes a locking groove for appropriately locking the adjustable collar pull line around the exposed object. A manipulator handle is detachably attached to the collar to facilitate placing the cover on and removing it from the exposed object. When the cover is appropriately above the exposed object, water and light are desirably prevented from entering the interior of the bag, whereby aquatic life forms such as filter feeders and plant life desirably cannot thrive in the cover.

[0016] U.S. Patent No. 6,152,064 discloses a protective propeller cover. The cover includes a flexible sleeve in which a buoyant material is placed to provide a flotation hull. A flexible propeller cover portion is secured to the flexible sleeve, and an end of the cover is releasably secured around the propeller. The flotation hull is positioned adjacent the propeller and extends above the waterline when the propeller is positioned below the waterline. The flotation hull is also used to protect swimmers from direct contact with the propeller when swimming near the vessel. The protective propeller cover device is further used to protect the propeller during transport or storage. The protective propeller cover device is further used as an anchor cover when the vessel is underway. The protective propeller cover device is further used as an emergency flotation device.

[0017] U.S. Patent No. 6,609,938 discloses a propeller protector slider for inboard and outboard motors of boats that are anchored, drifting, stranded, docked, stored, or out of the water in transit. The propeller protector slider ensures protection of the propeller from factors that cause pitting and damage to the propeller, and minimizes propeller-related damage. The protector propeller slider also provides a gauge for predicting the distance of the boat's propeller from a following vehicle.

[0018] U.S. Publication No. 2008 / 0020657 discloses an apparatus for protecting an outboard motor of a watercraft. The apparatus includes a positioning member adapted to be attached to the underside of a fin of the watercraft and a shroud engageable with the positioning member to provide an enclosure around the outboard motor. The shroud is buoyant and can float into sliding engagement with the positioning member. The shroud has an opening that is closed when the shroud is engaged with the transom of the watercraft to desirably prevent water from entering the interior of the shroud. A connecting device and a locking device are provided for releasably connecting the shroud to the positioning member.

[0019] In addition to using physical covers as shown above, other strategies have been adopted to reduce biofouling. U.S. Publication No. 2009 / 0185867 discloses a system and method for reducing vibration caused by eddy currents and drag around marine elements. The system includes but is not limited to a housing rotatably mounted around a marine element, the housing having relative edges defining a longitudinal gap, the longitudinal gap being configured to allow the housing to snap around at least a portion of the marine element. Fins can be positioned along each relative edge of the longitudinal gap, wherein each fin can extend outward from the housing. Fins can be positioned on the housing to desirably reduce vibration caused by eddy currents and minimize drag on the marine element. One or more antifouling agents can be placed on, in or around at least a portion of the housing, fins, or a combination thereof.

[0020] U.S. Patent No. 7,390,560 discloses a coating system for defouling a substrate. The system comprises a hull that is submerged in water or seawater for a long period of time. The system comprises a conductive layer, an antifouling layer, and a device for providing an energy pulse to the conductive layer. The conductive layer comprises a conductive polymer, such as carbon-filled polyethylene. The antifouling layer comprises a polymer with low surface free energy, such as polydimethylsiloxane. The layers are designed so that when the conductive layer is exposed to a pulse of electrical, acoustic or microwave energy or a combination thereof, the conductive layer separates from the antifouling layer.

[0021] U.S. Patent No. 6,303,078 discloses an antifouling structure for protecting an object in contact with seawater, the structure may include a water permeable fibrous material incorporating a molded thermoplastic resin or woven fabric containing a large amount of an antifouling agent, wherein the antifouling agent leaches from the structure into the seawater. According to this reference, it is important that the leachate maintains a high concentration of the antifouling agent near the object to prevent attachment of aquatic organisms. In addition, the environment created by many of the shell embodiments disclosed in this reference has extremely low dissolved oxygen levels (i.e., 8.3% or less), which tends to be highly anoxic and promotes excessive microbial corrosion and degradation of the protected object.

[0022] In order to directly shield and / or isolate these objects from biofouling, it is also known in the art that various surface coatings, paints, and / or other materials can be applied to the exterior surfaces of underwater objects. Many of these coatings and / or other materials rely on biocidal additives and / or metal additives (i.e., copper) that are expected to penetrate into the surrounding aqueous environment over time and interfere with various aspects of biofouling organisms. For example, divalent Cu 2 Interferes with enzymes on cell membranes and prevents cell division of various biofouling organisms, while tributyltin (TBT) biocides (now banned for use as marine biocides in many developed countries) and / or other organotin compounds kill or slow the growth of many marine organisms, and many of these substances may also act as endocrine disruptors. However, the process of preparing one or more underwater surfaces of an object and then applying and / or bonding such paints / coatings directly to one or more such surfaces is often an expensive and time-consuming process (which may even require removing the object from the aqueous environment and / or even dry-docking the vessel), and all of these coatings have a limited duration, typically lose effectiveness over time, and often have deleterious (and unwanted) effects on organisms in the surrounding aqueous environment. Similar difficulties exist for systems that rely on ablative and / or surface properties, such as hydrophobic, superhydrophobic, and / or non-sticky (i.e., non-sticky and / or superciliary) surfaces.

[0023] Recently, in an attempt to reduce and / or prevent biofouling, particularly in cooling and / or filtration water systems for large industrial facilities, systems that rely on the release or generation of active corrosive agents such as chlorine that are released into the aqueous environment (i.e., electrochlorination systems that generate hypochlorite compounds from seawater) have been used. In addition to the high cost of purchasing and / or operating such systems, such corrosive substances (which can be strong oxidizers in the case of chlorine) can cause deleterious effects far beyond their intended environments of use (i.e., once released, the corrosive substances can damage organisms in the surrounding aquatic environment), and many of these substances can enhance corrosion and / or degradation of the items they are intended to protect or related system components.

[0024] Various attempts have also been made in the art to completely isolate objects from biofouling elements in aqueous environments, such as by forming a completely sealed environment around the object to be protected from biofouling. However, in these cases, the liquid contained within the sealed environment (which is also in direct contact with the protected object) typically quickly becomes stagnant and / or anoxic, resulting in high levels of anaerobic corrosion of various materials, and particularly high levels of corrosion in anoxic sulfate-rich environments (such as anoxic seawater). Summary of the invention

[0025] Various inventions disclosed herein include fulfillment of the need for improved methods, apparatuses, and / or systems for protecting structures and / or substrates from microscopic and / or macroscopic fouling over extended periods of time when exposed to an aquatic environment, including situations where it may not be feasible, possible, and / or convenient to utilize a completely sealed "housing" or other type of exterior covering around an exposed substrate structure on a continuous basis. This may include situations where the substrate or other object is very large and / or may have extensive underwater support structures, where the substrate or other object is moving through an aqueous environment or providing some form of propulsive power (i.e., a boat propeller and / or hull), where the surrounding water in the aqueous environment is being circulated, consumed, and / or being utilized (i.e., for cooling water and / or being distilled for fresh water), and / or where sensors or other devices are being utilized to record and / or sample the surrounding aqueous environment.

[0026] The various inventions disclosed herein further encompass the realization that a completely sealed enclosure that completely isolates a substrate from a surrounding aqueous environment may not be sufficient to protect a substrate from various negative effects of an aqueous environment, as the "protected" substrate may be subject to corrosion or other effects due to lack of oxygen, acidity, and / or other conditions that may develop within and / or near the substrate (and / or other conditions associated with such an environment, such as the effects of microbial-induced corrosion). Thus, optimal protection of a substrate may be provided by an enclosure that at least partially (but not completely) isolates the substrate from various features and / or aspects of the surrounding aqueous environment.

[0027] In various embodiments, an anti-biofouling "enclosure" or "barrier" is described that can surround, abut and / or otherwise be positioned in proximity to a substrate or other object to filter, isolate, separate, insulate, protect and / or shield the substrate from one or more features or characteristics of the surrounding aqueous environment, including various embodiments using the embodiments described in co-pending U.S. patent application serial number 62 / 817,873, filed on March 13, 2019, and entitled "BIOFOULING PROTECTIVE ENCLOSURES" and co-pending Patent Cooperation Treaty (PCT) patent application No. PCT / US19 / 59546, filed on November 1, 2019, and entitled "DURABLE BIOFOULING PROTECTION," the disclosures of each of which are incorporated herein by reference in their entirety. More specifically, various embodiments of the enclosure will desirably create a "bounded," at least partially enclosed and / or differentiated aqueous environment in close proximity to the substrate that can be used to filter or screen the substrate from direct biofouling by some types of microscopic and / or macroscopic agents, as well as, at least in some cases, promote the formation of a relatively durable surface biofilm, coating or layer on the substrate and / or enclosure walls, which may potentially inhibit, hinder, avoid and / or prevent the settlement, recruitment and / or colonization of the substrate surface by undesirable types of biofouling organisms for extended periods of time (even in the absence of an enclosure) even in the absence of an enclosed environment. In many cases, openings, voids and / or fenestrations in the enclosure walls can allow controlled amounts of water exchange between the aqueous environment within the enclosure and the aqueous environment outside the enclosure, and may even alter the water chemistry and / or turbidity of the liquid contained within the enclosure compared to the surrounding open aqueous environment - to levels that may cause scaling and / or corrosion (or lack of scaling and / or corrosion) of the substrate contained within the enclosure in various ways, which may result in varying levels of clay, silt, finely divided inorganic and organic matter, algae, soluble colored organic compounds, chemicals and compounds, plankton and / or other microscopic organisms suspended in the differentiated liquid.

[0028] In various embodiments, the enclosures described herein are used to create an at least partially "enclosed," "localized," "contained," and / or "differentiated" aquatic environment adjacent to a submerged and / or partially submerged portion of a substrate or surface to be protected that is or becomes unfavorable to the settlement and / or recruitment of aquatic organisms that cause various types of biofouling (the aquatic environment may include surfaces that produce "negative" settlement cues, as well as surfaces that may lack and / or have levels of "positive" settlement cues that reduce one or more types of biofouling organisms). The enclosures and / or other configurations in various embodiments may also desirably filter, reduce, and / or prevent marine organisms that contribute to biofouling from entering the enclosure and / or contacting the submerged and / or partially submerged surfaces of the substrate.

[0029] In various embodiments, the enclosure can include a permeable formable matrix and / or fabric material, which in at least one exemplary embodiment can include a woven polyester fabric made from spun polyester yarn. In at least one additional embodiment, the use of spun polyester yarn can desirably increase the effective surface area and / or fibrillation of the fabric material on a microscopic and / or microscopic scale, which can desirably (1) result in a significant reduction in the "effective" or average size of natural and / or artificial openings extending through the fabric, (2) reduce the amount and / or width of "free space" within openings through and / or within the fabric, thereby potentially reducing the separation distance between microorganisms (in the inflowing / outflowing liquid) and the fabric surface and / or (3) alter and / or cause changes in the water quality within the enclosure in various ways. The reduced average opening size of the fabric will desirably increase "filtration" of liquids to reduce and / or prevent various biological organisms and / or other materials from entering the closed or bounded environment, while the reduced "free space" within one or more openings will desirably reduce the opportunity for organisms to freely pass through the fabric and / or reduce the rate and / or amount of "total water exchange" between the closed or bounded environment and the open aqueous environment. These factors will desirably result in a significant reduction or measurement of the size and / or viability of micro- and macro-organisms (as well as various organic and / or inorganic fouling and / or other compounds) entering / leaving the walls of the enclosure. In addition, these aspects will also desirably reduce the amount, extent and / or rate of biofouling or other degradation that may occur on the enclosure material itself and / or within one or more openings therein, thereby desirably maintaining the flexibility, permeability and / or other properties of the enclosure's fabric over an extended period of time.

[0030] In some embodiments, at least a portion of the fabric wall of the housing may be windowed and / or perforated to a sufficient degree to allow a certain amount of liquid and / or one or more other substances to pass and / or "filter" through the housing wall in a relatively controlled and / or metered manner (i.e., from the external or "open" aqueous environment to the differentiated aqueous environment and / or from the differentiated aqueous environment to the external or open aqueous environment), which desirably provides a certain level, amount and / or percentage of "bulk liquid flow" and / or "total liquid exchange" through the housing wall between the differentiated environment (inside the housing) and the surrounding open aqueous environment (outside the housing), as well as the possibility for various materials and / or compositions to diffuse or otherwise pass through the housing wall and / or its pores. Such movement of liquids and / or other compositions, in combination with various natural and / or artificial processes, desirably induces, promotes and / or produces within the enclosure a relatively "different" or dynamic "artificial" environment, particularly one having characteristics that differ in many respects from the dynamic characteristics of the surrounding aqueous environment, which desirably renders the differentiated environment "undesirable" to many biofouling organisms, and thereby reduces and / or eliminates the occurrence of biofouling within and / or immediately outside the enclosure. Additionally, the presence of a plurality of small perforations in the walls of the enclosure desirably provides various levels of filtration of the introduced and / or exchanged liquids, which can potentially reduce the number and / or viability of organisms that enter the enclosure through the wall holes and negatively impact organisms inside and / or outside the enclosure that may pass near the enclosure walls.

[0031] In various embodiments, the presence of the shell and any optional openings and / or perforations therethrough can create a "closed" or "partially closed" aqueous environment that can be less hostile to micro- and / or macro-fouling of the substrate than the surrounding aqueous environment, which can include the existence and / or presence of biofilm localized settlement cues within the closed environment at lower positive levels than the surrounding aqueous environment for biofilm localized settlement cues. Desirably, the shell will create "differences" in the composition and distribution of various environmental factors and / or compounds within the closed aqueous environment as compared to similar factors and / or compounds within the surrounding open aqueous environment, wherein these "differences" inhibit and / or prevent the occurrence of substantial biofouling (1) on the surface of the protected substrate, (2) on the inner wall surface of the shell, (3) within the voids of the openings and / or perforations in the shell wall, and / or (4) on the outer wall surface of the shell. In some embodiments, the shell can create a sedimentation cue gradient within the shell, thereby causing and / or driving some and / or all microscopic and / or macroscopic fouling organisms to be located at a distal end of the substrate, while in other embodiments, the shell can create a microenvironment close to the substrate that is not conducive to biofouling and / or other degradation of the substrate. In still other embodiments, the shell can be located adjacent to the substrate and / or in direct contact with the substrate, such as being directly wrapped around the substrate, and still provide the various protections described herein.

[0032] In various embodiments, the structure may include a plurality of smaller openings, perforations, and / or holes in the fabric, and one or more larger openings, such as an open bottom and / or top (or portions thereof) and individual openings on the sides of the shell. In various embodiments, a "large" opening may be defined as an opening in the shell that includes a surface area of ​​at least 10% or more of the outer surface area of ​​the shell wall, while in other embodiments, the large opening may include an area that is 2% or more, 5% or more, 15% or more, 20% or more, 25% or more, 30% or more, 35% or more, and / or 40% or more greater than the surface area of ​​the outer surface area of ​​the shell wall. In various other embodiments, a plurality of relatively smaller openings (i.e., 0.25% to 2% of the surface area of ​​the outer surface area of ​​the shell wall) may be functionally and / or structurally equivalent to one or more of the larger openings described herein.

[0033] As an example, the amount of dissolved oxygen in the liquid within the enclosure will desirably differ to a significant degree from the amount of dissolved oxygen in the liquid in the external aqueous environment, wherein changes in dissolved oxygen in the differentiated liquid may reflect, lag, and / or "lag" dissolved oxygen levels in the external aqueous environment (in the amount of change). Desirably, such dissolved oxygen levels in the differentiated liquid are generally less than the dissolved oxygen levels of the surrounding aqueous environment (although in various embodiments, the dissolved oxygen levels may be equal to and / or greater than the dissolved oxygen levels of the surrounding environment, including on a periodic and / or continuous basis), and in various embodiments, the dissolved oxygen levels may fluctuate at values ​​above levels that contribute to sulfate-reducing bacteria or similar bacterial activity (i.e., microbiologically induced corrosion - "MIC") and / or other anoxic degradation / corrosion levels, wherein the fluctuations themselves desirably contribute to inhibiting and / or controlling the dominance of any single undesirable type or group of microorganisms and / or macroorganisms within the enclosure or various sections or portions thereof.

[0034] In various embodiments, a gradient of dissolved oxygen and / or other water chemistry may form within the liquid of the housing between the inner wall of the housing and the outer surface of the protected substrate, wherein this gradient may create a "more suitable region" near the inner wall of the housing and / or a "less suitable region" near one or more surfaces of the substrate, which in some embodiments may cause various microorganisms to migrate toward the inner wall of the housing and / or away from one or more surfaces of the substrate (as an example, this may be due to the increase in the percentage of dissolved oxygen that may be closer to the housing wall), and potentially promote the inability of some microorganisms to colonize, settle, reproduce and / or grow on one or more surfaces of the substrate. In various embodiments, this gradient may be at least partially due to the influx of water through and / or into the housing, and / or may be at least partially due to the outflow of water through and / or out of the housing. The resulting "exchange" of water into and out of the housing and / or out of the housing, and the various concentrations of chemicals and / or compounds contained therein, will desirably reduce the amount, extent and / or rate of biofouling or other degradation that may occur to the substrate in its natural (i.e., unprotected) state.

[0035] In various embodiments, water or other aqueous media entering and / or leaving the enclosure will desirably accomplish this circulation primarily in a "bulk" manner, wherein local variations in water velocity and / or "current" within the enclosure will be minimized. The resulting relatively static nature of the water within the enclosure will desirably reduce and / or inhibit significant "mixing" of the water within the enclosure, desirably resulting in greater levels of stratification and / or differentiation within the enclosure, which may include stratification based on oxygenation levels (i.e., chemostrata) and / or other properties (i.e., salinity, density, temperature), thereby potentially resulting in the creation of localized anoxic and / or sea-quiet zones within the enclosure (which may be suspended within the enclosure and / or separated from the surface of the substrate by other water regions within the enclosure). In addition, water exiting the enclosure (which may include various metabolic waste products and / or harmful compounds (including various known and / or unknown microbial "toxins") and / or other inhibitory compounds produced within the differentiated environments) will desirably "linger" within the pores of the enclosure and / or near the outer walls of the enclosure as a "cloud" of such "waste products" / compounds for varying lengths of time, which will desirably reduce and / or prevent colonization of the enclosure walls (including outward-facing walls) by fouling organisms.

[0036] In an exemplary embodiment, an enclosure may be utilized in proximity to a substrate to create an oxygen-depleted zone within the enclosure, wherein at least a portion of the oxygen-depleted zone is proximate to or in contact with the substrate, wherein in some embodiments, the oxygen-depleted zone may include the entire differentiated aqueous environment (i.e., within the enclosure), while in other embodiments, the oxygen-depleted zone may include only a portion of the differentiated aqueous environment. Desirably, various aspects of the unique design and arrangement of the enclosure will allow one or more natural processes to initially create the oxygen-depleted zone, although in some embodiments, additional actions and / or activities may be taken to initiate, accelerate, maintain, delay, reduce, and / or supplement one or more natural processes that may affect the resulting oxygen-depleted zone.

[0037] Desirably, the shell will provide a unique protective environment in an aqueous environment, wherein the number and / or diversity of bacteria and / or other microorganisms within the shell may be different from those bacteria and / or other microorganisms located outside the shell. In addition, the shell can produce multiple differentiated environments within the shell, which can include a first differentiated "environment" that can be quantified as "adjacent to the inner wall of the shell" (i.e., for example, within a few millimeters of the inner wall of the shell) and at least one second differentiated "environment" that can be quantified as the outer surface of the adjacent substrate (i.e., within a few millimeters of the outer surface of the substrate). In various exemplary embodiments, a given differentiated environment can cause or promote the formation of one or more biofilms within the shell, which can include forming a biofilm on the surface of the substrate, which may be different in various aspects from the biofilm that can be formed on the substrate in the aqueous environment without a different biofilm on the inner surface of the shell and / or the shell wall or in the pores. For example, a substrate biofilm in a "closed" or differentiated environment may incorporate a lower / less diverse diversity of bacteria or other microorganisms, or may include a "thinner" layer than a biofilm typically formed on the surface of an unprotected equivalent substrate (which may facilitate heat transfer through the film and / or adjacent surfaces in a desired manner). In various cases, such a differentiated biofilm may be advantageous for preventing and / or reducing micro- and / or macro-fouling of the substrate or for other reasons.

[0038] In some embodiments, the unique protected environment within the aqueous environment can cause a unique number and / or diversity of bacteria and / or other microorganisms within the shell, which can cause or promote the formation of one or more biofilms within the shell, wherein such biofilms may be "less firmly attached" to the substrate than biofilms typically encountered in unprotected environments. Such biofilms can promote the removal and / or "scraping" of fouling organisms from the substrate and / or from the intermediate biofilm layer. In such cases, the microbial flora and / or microfauna can include different phyla (i.e., different bacteria and / or cyanobacteria and / or diatoms) than those located outside the shell.

[0039] In various embodiments, the presence of the shell and various perforations therethrough can create a "differentiated" aqueous environment that can be less favorable to micro- and / or macro-fouling of the substrate than the surrounding aqueous environment, which can include the presence and / or presence of biofilm localized settlement cues within the differentiated environment at lower positive levels than the surrounding aqueous environment for biofilm localized settlement cues. Desirably, the shell will create "differences" in the composition and distribution of various environmental factors and / or compounds within the differentiated aqueous environment as compared to similar factors and / or compounds within the surrounding open aqueous environment, wherein these "differences" inhibit and / or prevent the occurrence of substantial biofouling (1) on the surface of the protected substrate, (2) on the inner wall surface of the shell, (3) within the voids of the openings and / or perforations in the shell wall, and / or (4) on the outer wall surface of the shell. In some embodiments, the shell will create a sedimentation clue gradient within the shell, thereby causing and / or driving some and / or all microscopic and / or macroscopic fouling organisms to be located at a distal end of the substrate, while in other embodiments, the shell can create a microenvironment close to the substrate that is not conducive to biofouling and / or other degradation of the substrate. In still other embodiments, the shell can be located adjacent to the substrate and / or in direct contact with the substrate, such as being directly wrapped around the substrate, and still provide the various protections described herein.

[0040] In various other embodiments, the presence of a perforated shell wall can similarly affect the presence / absence of various water chemistry factors and / or nutrients and / or waste within a differentiated environment and / or a portion thereof, as compared to the surrounding aqueous environment. For example, pH, total dissolved nitrogen, ammonium, nitrate, nitrite, orthophosphate, total dissolved phosphate, and / or silica can vary between a differentiated environment and the surrounding open aqueous environment, and even within a differentiated environment, the levels of such nutrients can also vary across closed or bounded aqueous regions. Typically, near at least a portion of the shell wall (i.e., the "upstream portion" based on the direction of the bulk water flow), the level of water chemistry, nutrient levels, and / or waste metabolites in the liquid within the shell may be closer to the level of the liquid level outside the shell, wherein typically greater changes can be seen further within the shell and / or near the substrate surface.

[0041] In various embodiments, the presence of an enclosure as described herein may alter water chemistry such that fouling organisms that may land on a substrate may not settle or attach to the substrate and / or may not be able to reproduce and / or colonize the substrate due to various "unsuitable" conditions within the differentiated environment, which prevent the organisms from growing (including growing as rapidly as comparable organisms located outside the enclosure), reproducing and / or passing through one or more of the required natural processes and / or stages that these organisms undergo to become fully functional large fouling organisms. For example, various chemical changes may occur within the enclosure (compared to the surrounding open aquatic environment), including lower dissolved oxygen levels, altered pH, different nutrient levels and / or concentrations, waste product levels and / or lack of moving water, etc. within the enclosure. In many cases, when a substrate is placed within the various enclosures described herein, fouling organisms may even disconnect and / or "die off" from already fouled surfaces, which may stop and / or reduce fouling of the substrate, as well as may loosen and / or detach some existing biofouling organisms and / or skeletal remains, such as shells, bones, exoskeletons and / or associated support structures, from one or more fouled surfaces.

[0042] In various embodiments, the arrangement, small size and / or distribution of the perforations of the shell wall and the presence of various lines and / or line portions (i.e., fibrils) positioned therein may limit, prevent and / or regulate the presence and / or availability of sunlight or other light / heat energy (including artificial and / or bioluminescent energy sources) within the shell or various portions thereof, including limiting and / or preventing various energy sources (such as sunlight for photosynthesis) from being readily available to various microorganisms and / or other degradation processes, particularly where the shell is utilized closer to the surface of an aqueous environment or in proximity to such other energy sources. If desired, the availability or presence of such energy sources near the shell wall (i.e., through the perforations) may cause some active organisms to aggregate and / or pool near the inner wall of the shell, thereby desirably reducing their presence near the surface of the substrate to be protected. In various alternative embodiments, the light source or other energy source may be positioned in the surrounding aqueous environment near the shell and / or may be positioned within the shell in various locations, including near the substrate to be protected, thereby increasing the availability of such energy sources near and / or within the shell. Such embodiments may be particularly useful in limiting the presence and / or growth of biofouling organisms that are sensitive to added energy sources (ie, such as providing a light source that inhibits zebra mussels, which generally prefer darker environments).

[0043] In various embodiments, the arrangement, small size and / or distribution of the perforations of the shell wall and the presence of various lines and / or line portions therein can limit, prevent and / or regulate the location and / or amount of one or more higher velocity mass water flows that may occur within the shell or its various portions, including limiting and / or preventing various types of laminar and / or turbulent flows (i.e., localized water flows or "jets") of liquid within the shell and / or near the substrate. In some embodiments, the relatively "slow" but slightly less than completely "still" nature of the water that can be obtained within the shell can prevent a large number of non-sessile microorganisms from contacting the substrate or a boundary layer adjacent thereto. In addition, limited liquid flow within the shell can allow a thinner / thicker aqueous liquid boundary layer to exist near the protected substrate and / or shell wall, which can further limit microorganisms or contact with the protected substrate and cause or allow the formation of a thinner / thicker biofilm on the substrate than would normally exist in one or more more active flow conditions of an open aqueous environment.

[0044] In at least one alternative embodiment, the various advantages of the present invention can be provided by an impermeable enclosure (comprising plastic, wood and / or metal wall sheets or panels, etc.) in combination with a supplemental and / or artificial water exchange structure (such as a powered pump or "check valve" arrangement, a propeller system and / or a petal system) that provides the desired level of water exchange between the differentiated aqueous environment and the surrounding open aqueous environment.

[0045] In some embodiments of the present invention, some or all of the biofouling protection and / or effectiveness described herein for protected substrates may desirably be provided by the housing and its permeable formable matrix, fiber matrix, and / or fabric wall material without the use of various supplemental anti-biofouling agents, while in other embodiments, the housing may include a permeable formable fiber matrix and / or fabric wall material that incorporates one or more bactericides and / or antifoulants into some or some portions of the wall structure and / or its coating. In some embodiments, one or more bactericides and / or antifoulants may provide biofouling protection for the housing wall and / or components (where the housing itself provides a certain level of biofouling protection for the substrate), while in other embodiments, one or more bactericides and / or antifoulants may provide a certain level of biofouling protection for the substrate itself, while in still other embodiments, one or more bactericides and / or antifoulants may provide biofouling protection for both the housing and the substrate and / or various combinations thereof.

[0046] In some embodiments, the enclosure can provide biofouling protection to both the substrate and the enclosure wall to varying degrees even in the absence of supplemental biocides or other fouling protective substances, inhibitors, and / or toxins that can be integrated into and / or supplementally provided to the enclosure structure. For example, when an enclosure as described herein is placed around a substrate and creates one or more of the disclosed differentiated environments, the one or more environments can also increase the concentration of various metabolic waste products, and various processes and / or metabolic activities occurring within the enclosure can produce one or more substances (e.g., hydrogen sulfide or NH 2 O) that are harmful, injurious, toxic, and / or otherwise negatively impacting fouling organisms. 3 -N – ammoniacal nitrogen). For example, NH 3 -N is the undissociated form of ammonia, also known as free ammonia nitrogen (FAN) or ammoniacal nitrogen, which is found to be harmful and / or toxic to microorganisms because it can permeate cell membranes. In some embodiments, desired concentrations of such harmful compounds (including various known and / or unknown microbial "toxins") and / or inhibitory compounds may develop within the enclosure (and these concentrations may then be continuously "replenished" by various processes occurring within the enclosure), wherein the compounds may reside in differentiated aqueous regions within the enclosure and / or elute through the walls of the enclosure, thereby potentially creating a local "cloud" of harmful chemicals that protects the outer walls of the enclosure from fouling organisms to some extent. However, once these compounds leave the enclosure, these harmful and / or inhibitory compounds may be rapidly diluted and / or decomposed by various natural processes, thereby avoiding significant concerns about the long-term effects of these substances on the environment at a distance from the enclosure. In addition, because the process of generating these compounds within the enclosure is continuous and / or periodic, the enclosure can continuously generate and / or elute these inhibitory compounds at relatively constant levels on an uncertain basis without the need for an eluent reservoir and / or external replenishment or external power source.

[0047] In at least one exemplary embodiment, the shell may include a permeable, formable fibrous matrix of a polyester fabric made from spun polyester yarns, which may be coated on at least one side (e.g., the outwardly facing surface of the shell) with a biocide compound or a coating or paint containing a biocide, wherein at least some of the biocide compound at least partially permeates into the bulk of the fabric. In at least one additional embodiment, the use of ring-spun polyester yarns may desirably increase the effective surface area and / or fibrillation of the fabric material on a microscopic and / or microscopic scale, which may desirably (1) result in a significant reduction in the average size of natural openings extending through the fabric and / or (2) reduce the amount and / or width of "free space" within openings through and / or within the fabric, thereby potentially reducing the separation distance between microorganisms (in the inflowing / outflowing liquid) and one or more biocide coatings residing on the fabric. In such embodiments, the reduced average opening size of the fabric will desirably increase the "filtration" of liquids to reduce and / or prevent various biological organisms and / or other materials from entering the closed or bounded environment, while the reduced "free space" within one or more openings will desirably increase or amplify the effect of the biocide on organisms passing through the enclosure (including an increased likelihood of direct contact between the biocide and various organisms) due to the close proximity of the biocidal coating. These factors will desirably result in a significant reduction in the size and / or viability of microorganisms and macroorganisms (as well as various organic and / or inorganic fouling) that enter the enclosure. In addition, the presence of one or more biocide coatings and / or one or more paints and / or one or more additives on and / or in the fabric of the enclosure will desirably significantly reduce the amount, extent and / or rate of biofouling or other degradation that may occur on the enclosure material itself and / or within one or more openings therein, thereby desirably maintaining the flexibility, permeability and / or other properties of the fabric of the enclosure over an extended period of time.

[0048] In some embodiments and / or some aqueous environments, the presence of an optional biocide coating at least on the outer surface of the flexible shell material will desirably reduce the thickness, density, weight and / or degree of biofouling and / or other degradation experienced on and / or within openings within the shell itself, which will optimally maintain a desired level of water exchange between the shell and the surrounding environment and / or extend the useful life of the shell in its desired location around the substrate. In many cases, biofouling of the shell can significantly increase the weight and / or stiffness of the shell, which can damage the shell and / or structures attached to the shell (including the substrate itself), as well as adversely affect the buoyancy of the shell and / or any objects attached thereto. In addition, biofouling of the shell itself can reduce the flexibility and / or ductility of various fabric components, which can cause and / or contribute to premature tearing and / or failure of the fabric and / or associated attachment mechanisms in dynamic aqueous environments. Additionally, biofouling formation on / in the shell may potentially “clog” or reduce the size of openings through and / or within the shell fabric and / or close openings, which may potentially alter the permeability and / or liquid exchange rate between the differentiated environment and the surrounding dynamic and / or open aqueous environment, possibly leading to undesirable conditions (i.e., low dissolved oxygen levels and / or hypoxia) and / or corrosion or other problems occurring within the shell.

[0049] In at least one embodiment, the housing can include an initial biocide treatment that elutes and / or otherwise distributes within a limited period of time after the housing is deployed, wherein this period of time is sufficient to allow other features of the housing to develop a differentiated environment, wherein the differentiated environment can produce various inhibitory substances to provide subsequent biofouling protection to the substrate and / or housing after the initial biocide elution is reduced to a lower and / or ineffective level and / or elution or distribution has ceased. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] The foregoing and other objects, aspects, features and advantages of the embodiments will become more apparent and can be better understood by referring to the following description made in conjunction with the accompanying drawings, in which:

[0051] Figure 1 An exemplary embodiment of a housing in the form of a kilt-like or skirt-like structure is depicted;

[0052] Figure 2 Depicted Figure 1 A partial cross-sectional view of a skirt shell system;

[0053] Figure 3A depicts a perspective view of an exemplary sheet or wall for use in various biofouling protective systems described herein;

[0054] Figure 3Bdepicts a perspective view of another embodiment of a peripheral ring or curtain biofouling protection system;

[0055] Figure 3C depicts a perspective view of an exemplary embodiment of a filter module or filter element for a biofouling protection system;

[0056] Figure 3D Another exemplary embodiment of a peripheral ring or curtain biofouling protection system is depicted;

[0057] Figure 4A depicts a cross-section of another embodiment of a skirt housing positioned at least partially around a floating object;

[0058] Figure 4B depicts a cross-section of another exemplary embodiment of a skirt-type housing positioned at least partially around a floating object;

[0059] Figure 5 depicts a side view of another exemplary embodiment of a skirt or peripheral enclosure biofouling protection system positioned around an offshore oil platform;

[0060] Figure 6 Another exemplary embodiment of a biofouling protection system having a plurality of housings and partial housings positioned around various support legs of an oil rig is depicted;

[0061] Fig. 7A and 7B Depicts top and perspective views of a U-shaped biofouling protective enclosure positioned within a standard marine slide;

[0062] Figure 7C and 7D depicts side and perspective views of another exemplary U-shaped biofouling protective enclosure incorporating a hanging curtain closure;

[0063] Fig. 8A and 8B Depicted are components of a biofouling protective system comprising a plurality of deployable roll sheets;

[0064] Fig. 9A depicts a perspective view of another exemplary embodiment of a fabric skirt section and buoy of a biofouling protective system;

[0065] Fig. 9B and 9C Depicting a sliding or tongue-and-groove connection between adjacent floating boom sections of a biofouling protective system;

[0066] Fig.9D and 9Edepicts a closable flap that may be engaged to protect a connection between adjacent floating boom sections of a biofouling protective system;

[0067] Fig.10 depicts a side view of an exemplary embodiment of a fabric sheet and associated structure for attachment to a commercially available floating boom system;

[0068] Fig.11 depicts a side view of another exemplary embodiment of a skirted biofouling protective enclosure;

[0069] Fig. 12A and 12B depicts a view of another exemplary embodiment of an enclosure for reducing biofouling in intake piping and associated equipment of a manufacturing plant or other facility;

[0070] Fig.13A depicts a simplified perspective view of an exemplary embodiment of a natural or artificial reservoir or pond;

[0071] Fig. 13B and 13C An exemplary embodiment of a labyrinth or tortuous path biofouling protective enclosure is depicted;

[0072] Fig.13D Alternative embodiments of labyrinth or tortuous path biofouling protective enclosures are depicted;

[0073] Fig.14A depicts a scanning electron microscope (SEM) micrograph of an exemplary spun yarn for use in a biofouling protective enclosure;

[0074] Fig. 14B Depicted Fig.14A A cross-sectional SEM micrograph of the central body portion of the yarn;

[0075] Fig. 14C depicts SEM micrographs of knitted fabrics comprising PET spun yarns;

[0076] Fig.15A An exemplary fabric material in the form of a rolled sheet for use in a biofouling protective enclosure is depicted;

[0077] Fig. 15B Another exemplary fabric material in the form of a rolled sheet for use in a biofouling protective enclosure is depicted;

[0078] Fig.16 depicts a cross-sectional view of an exemplary permeable fabric showing various pore openings and simplified channels;

[0079] Fig.17AAnother exemplary embodiment of an uncoated polyester woven fabric is depicted;

[0080] Fig. 17B An embodiment of 17A having a coating is depicted;

[0081] Fig.18A Depicts natural uncoated burlap fabric;

[0082] Fig.18B and 18C Depicted are methods for applying solvent-based biocidal coatings and water-based biocidal coatings. Fig.18A fabric;

[0083] Fig.19A An uncoated polyester fabric is depicted;

[0084] Fig.19B Depicts coating with a bactericidal coating Fig.19A fabric;

[0085] Fig.19C An uncoated spun polyester fabric is depicted;

[0086] Fig.19D Depicts coating with a bactericidal coating Fig.19C fabric;

[0087] Fig.19E An uncoated spun polyester cloth is depicted;

[0088] Fig.19F Depicted after coating Fig.19E an uncoated side of a spun polyester fabric;

[0089] Fig. 20 depicts detection of rhodamine concentration over time in an exemplary housing;

[0090] Fig.21 Depicted are the various plankton types and conditions identified in the various enclosure embodiments;

[0091] Fig. 22 depicts a perspective view of another exemplary embodiment of an enclosure for protecting a substrate from biofouling, the enclosure incorporating a wall structure having multiple layers;

[0092] Fig.23 depicts one exemplary embodiment of an aqueous flow mechanism for a supplemental pumping system for use with various embodiments of a biofouling protective enclosure; and

[0093] Fig.24 The distribution of various bacterial phyla in biofilms formed on various substrates in seawater was depicted;

[0094] Fig.25 The percentage reduction in heat transfer is depicted. DETAILED DESCRIPTION

[0095] The disclosure of the various embodiments described herein is provided with sufficient specificity to meet statutory requirements, but these descriptions are not necessarily intended to limit the scope of the claims. The claimed subject matter may be embodied in a variety of other ways, may include different steps or elements, and may be used in conjunction with other technologies including past, present, and / or future developments. Except for explicitly describing the order of the various steps or the arrangement of the elements, the description provided herein should not be interpreted as implying any particular order or arrangement among or between the various steps or elements.

[0096] Disclosed herein are various readily assembled and / or usable housings and / or other devices that can be placed near, around, within, on top of, and / or below a substrate or other object positioned within (or placed within) an aqueous environment or aqueous containment tank susceptible to biofouling. In various embodiments, disclosed are systems, devices, and methods that can protect a submerged and / or partially submerged substrate or other object (or portion thereof) from aqueous biofouling, including that the substrate develops biofouling resistance, and may retain biofouling resistance, for some extended period of time after the housing is opened and / or removed.

[0097] In various embodiments, a protective shell is disclosed that can be formed from relatively inexpensive and readily available materials such as polyester, nylon or rayon fabrics and / or natural materials such as cotton, linen or burlap fabrics (or various combinations thereof). In various embodiments, the shell can include treatment and / or biodegradability features that allow the shell or a portion thereof to decouple from the substrate and / or support structure after a certain amount of exposure to an aqueous environment, decompose and / or otherwise degrade, which may include degradation and / or detachment after forming a desired biofilm or other layer on the substrate.

[0098] In the various embodiments disclosed herein, the terms "differentiated aqueous environment" and / or "local aqueous environment" are intended to broadly cover some and / or all aqueous areas whose water chemistry has or will be changed due to the impact and / or presence of the shell, and the differentiated aqueous environment and / or local aqueous environment may include one or more of the following (and / or any combination thereof): 1) any water within the inner wall of the shell (i.e., a "closed" or "differentiated" aqueous environment), 2) any water within any pores or spaces between the inner and outer surfaces of the shell (i.e., an "entrained" aqueous environment) and / or 3) any water in close proximity to the outer surface of the shell (i.e., the "proximal" aqueous environment).

[0099] Although in some embodiments, the housing may substantially surround and / or enclose the outer surface of the substrate, in some alternative applications, the housing may desirably be positioned and / or configured to protect a substrate positioned proximate and / or external to the housing, wherein an "open aqueous environment" may be considered to be positioned within the housing, and a "closed" or "differentiated" aqueous environment may be positioned between the outer wall of the housing and the inner wall of the substrate. For example, in a water storage tank, the inner wall of the tank may constitute the "substrate" to be protected, and some or all of the water pumped into the tank (i.e., pumped from an external environmental source such as a stream, lake, well, harbor, or reservoir) may constitute the "open aqueous environment" from which protection of the substrate is sought. In such cases, a housing as described herein may be positioned around a water inlet (or the housing wall may be positioned at some point between the water inlet and the tank wall), wherein the housing desirably creates one or more "differentiated" environmental conditions proximate to the tank wall, and thereby protects the tank wall from the various effects of biofouling as described herein.

[0100] In a similar manner, for embodiments that may involve "filtering" and / or "straining" liquids using the housing and / or portions thereof, the "open aqueous environment" may be considered to be the upstream source of liquid water (or other liquid) prior to passing through the housing walls, and the "differentiated aqueous environment" may be considered to be the liquid after having passed through one or more housing portions. At least one alternative embodiment may include a housing element that may line the interior wall of a tank, holding chamber, or dispensing unit, such as a biofouling protective "windbag" or similar design that may be deployed within an aqueous pipe flange.

[0101] It should be understood that in various alternative embodiments, "enclosed" substrates as described herein encompass partially enclosing a substrate with an enclosure or other device to an extent sufficient to cause some and / or all desired filtration and / or water chemistry changes when in proximity to the protected substrate, including enclosures that may not completely seal or isolate the substrate from the surrounding aqueous or other environment. For example, an enclosure protecting a hull or other submerged and / or partially submerged portion of a boat or vessel may be considered to "enclose" the hull described herein, even if the enclosure only encompasses some or all of the underwater portions of the hull and portions of the enclosure that may be open to the surrounding air (i.e., including portions open to the "above water" environment), portions of the aqueous environment, and / or to other objects such as wooden structures, rock walls, solid metal sheets, etc. In a similar manner, an enclosure having various notches, openings, seams, crevices, cracks, and / or missing wall elements therein can be considered to "enclose" a substrate as described herein, wherein sufficient enclosure structure is present to desirably cause some and / or all of the desired water chemistry changes and / or filtration functions to occur proximate the enclosure and / or protected substrate, thereby protecting the enclosure and / or substrate from biofouling as described herein and / or reducing the amount of biofouling of the enclosure / substrate to an acceptable level and / or causing the formation of a desired biofilm on the substrate.

[0102] In at least one embodiment, a partially open or skirted enclosure is disclosed, such as an enclosure having a lower edge of the enclosure wall proximate to and / or contacting the bottom surface of the harbor floor. In at least one possible embodiment, the enclosure may include features that partially and / or completely "seal" some or some portions of the enclosure against other objects such as seawalls, hull portions, larger hulls, submerged and / or partially submerged structures, and / or the bottom surface / mud of the seafloor. In other embodiments, the enclosure may desirably include sufficient depth to provide the biofouling protection described herein, but will be shallow enough to avoid contacting the bottom of the aqueous medium during low tide (i.e., for example, a length of 3 feet, 6 feet, and / or 9 feet underwater). If desired, the bottom portion of the vertically oriented sheet may include fenestrations, slits, striations, and / or perforations that may inhibit, but not completely prevent, water from flowing into and / or out of the space between the bottom of the enclosure and the seafloor.

[0103] In some embodiments, a "partial" enclosure and / or "overhang" of a natural water column near a submerged structure can provide significant biofouling protection and / or improvements in preventing and / or reducing biofouling of a partially or fully submerged structure, particularly where some "active" measures can be taken simultaneously to desirably artificially induce and / or accelerate some portion of the various water chemistry changes described herein. In other embodiments, the design and / or positioning of a "partial" enclosure or similar structural element can utilize hydrodynamics (i.e., generating artificial water flow, such as pumping or redirecting water and / or utilizing natural water flow, such as currents, tides, etc.) to improve and / or accommodate the presence of various openings in the enclosure, thereby preventing and / or reducing biofouling of a partially or fully submerged structure protected thereby.

[0104] If desired, a "partially open" enclosure may be effectively utilized in some environments without significantly impeding the flow of water and / or other materials into and / or out of submerged inlets / outlets of a fully or partially submerged structure, which may include inlets / outlets of a ship hull and / or plant, heat exchangers, power generation structures and / or water treatment plants.

[0105] In various embodiments, a skirt or kilt-type protective system may include separate elements for a housing or similar structure comprising a plurality of vertically oriented "sheets" or similar structures that can be deployed into water surrounding an object or portion thereof, wherein a portion of the sheet extends downwardly below the object to be protected and, in some embodiments, extends significantly below the upper edge of the skirt, object and / or water surface, and in some embodiments includes extending within and / or beyond a portion of a light-transmitting zone (i.e., a sunlit zone) of the water body, wherein the protective system desirably creates a partially or completely low-light zone (i.e., a low-light zone) of water near the object, or creates a partially and / or completely confined water area that induces and / or maintains a desired chemical change in the water near the protected object, thereby desirably inhibiting biofouling. In various embodiments, the protective system desirably can further induce some level of permeability variation to the sunlight passing therethrough, which in some embodiments can reduce and / or prevent a significant amount of available sunlight from being admitted into this low light band (i.e., available to organisms for photosynthesis) through the top of the enclosure in conjunction with barrier materials (e.g., sheets, meshes, screens, and / or other barriers) to reduce and / or eliminate the passage of sunlight (and / or various wavelengths and / or components thereof) between objects and the upper portion of the enclosure wall. In various embodiments, these barrier materials can also inhibit or prevent physical mixing of oxygen with water within the barrier by wave and / or wind action.

[0106] In other embodiments, a skirt or peripheral housing may be placed around an offshore oil platform to desirably reduce and / or eliminate biofouling of various portions of the support structure or "legs" surrounding the platform. In such embodiments, the housing walls may be deployed around most of the perimeter of the entire support structure and extend vertically downward from a drum dispenser or "buoy" into the water (or may be secured directly to the platform and / or legs), wherein the depth of one or more of the housing walls may be increased and / or decreased as desired. Desirably, the housing walls will completely and / or partially surround the platform support (which may include surrounding a single support leg with a separate housing or the entire support structure in a single housing), and will extend to a sufficient depth to cause desired water chemistry changes in various portions of the enclosed or bounded body of water, including changes near the shallower portions and / or surface of the enclosed or bounded body of water. If desired, one or more of the housing walls may be raised or lowered as desired to cause desired water chemistry changes if such chemistry is being monitored (i.e., for example, around a drilling rig or at a remote monitoring station). In a similar manner, one or more openings, partitions, and / or sections in or between housing walls may be opened and / or closed as desired to desirably alter water chemistry in a desired manner.

[0107] If desired, the antifouling system can include a free-floating hull, wherein the hull walls can be supported by floating booms that can wrap around or encircle the protected vessel. In various embodiments, the disclosed structures and / or components thereof can be directly attached to and / or suspended directly from a dock or boat slipway. For example, a U-shaped hull can be positioned within a standard boat slipway, wherein the hull walls are connected to one or more adjacent docks and / or other structures.

[0108] In various embodiments, the housing may be used to periodically provide biofouling protection to the protected substrate, which may include interrupting biofouling protection when water flow near the protected substrate may increase, decrease, and / or some other change in water flow is desired, wherein biofouling protection may be restored at a time period when water flow near the protected substrate has returned to a "normal" or desired level (which may be the same or different than the water flow level before the change). For example, the housing may include one or more subsurface openings that may be automatically and / or controlled by a user, which may be opened when an increase in water flow into and / or out of the housing is desired. Such situations may include the removal of the substrate from the housing, the need to sample the external environmental water quality, and / or the need for large amounts of cooling and / or other water (e.g., through submerged intakes and / or discharges in the substrate hull). In other embodiments, the housing may be designed to increase the flow of water through the housing wall during a desired time period, which may reduce and / or eliminate some or all of the biofouling protection provided by the housing during one or more increased flow time periods, but once the water flow decreases below a predetermined design threshold, the biofouling protection may be restored.

[0109] In at least one exemplary embodiment, a housing design having particular utility as an anti-biofouling and / or filtration system for systems that utilize seawater and / or fresh water as a cooling water source may be provided. In this embodiment, a floating housing or a partially / fully submerged housing or "reservoir" in an aqueous environment may be provided, wherein the housing contains more aqueous fluid than the amount that may be immediately required by the cooling system during normal use. For example, if the cooling system requires 1000 gallons of water per minute during normal operation, the "reservoir" (i.e., the body of water between the housing wall and the intake or inlet of the cooling water system within the housing) may desirably contain at least 10,000 gallons, at least 20,000 gallons, at least 50,000 gallons, at least 100,000 gallons, at least 500,000 gallons, and / or at least 1,000,000 gallons and / or more of water. In one exemplary embodiment, the water inlet of the cooling system can be located near the top of the reservoir to desirably draw water having a relatively low dissolved oxygen level into the inlet for use by the cooling device, wherein "replacement" water having a relatively high dissolved oxygen level is drawn into the bottom and / or any lower side openings or gaps of the reservoir. During the time it takes for the bulk of water molecules and / or droplets to be transported up the water column within the reservoir, natural and / or artificial deoxygenators within the water column can desirably reduce the dissolved oxygen level in the water such that the dissolved oxygen level is slightly depleted prior to entering the inlet. However, in at least one alternative embodiment, the water inlet can be located near the bottom of the housing and / or the bottom surface of the reservoir, which water inlet may be particularly desirable because of the typically cooler water within the housing / reservoir for use by the cooling device.

[0110] In at least one exemplary embodiment, methods for determining the appropriate design, size, shape, and / or other features of an enclosure can be used to determine a recommended minimum enclosure or bounded volume and / or water exchange rate to desirably reduce and / or eliminate biofouling within the enclosure. In some embodiments, such as in a membrane filter configuration, where an enclosure can be utilized to provide a cooling water source and / or other source of water to a manufacturing plant (i.e., a power plant, desalination plant, refinery, and / or other manufacturing plant), the disclosed methods can potentially be used to reduce and / or eliminate biofouling within the plant's water and / or other conduits, and in some embodiments, no additional filtering and / or microfiltration of the water is required. In various embodiments, the enclosure may include multiple filters or modular filter panels, wherein one or more filters / panels may be replaced when desired. In some embodiments, the filter panels may be replaced while the system is operating normally.

[0111] In various embodiments, under certain conditions, the design and use of the enclosure may potentially promote, cause and / or facilitate the formation of layers, biofilms and / or deposition of materials on the substrate and / or enclosure walls, thereby reducing, repelling, inhibiting and / or preventing subsequent attempts by microorganisms and / or macroorganisms to colonize, recruit and / or contaminate some or all of the protected substrate (i.e., providing a certain level of "biofouling inoculum" to the substrate). For example, various embodiments of the enclosure disclosed herein may cause the creation of a unique aqueous environment within the enclosure, resulting in the creation of a unique mixture of microorganisms and / or microbial flora within the environment (including within one or more aqueous layers near the surface of the substrate). In many embodiments, the unique mix and / or distribution of microorganisms / microbial flora within the enclosure may cause and / or influence the creation of a microbial biofilm or other layer on the substrate, which in combination with various surface bacteria may release fouling organisms that affect the settlement, recruitment and / or colonization of the substrate. In various embodiments, once a unique microbial biofilm layer is established, this layer can remain durable and / or self-replenishing, which can continue to protect the substrate from certain types and / or amounts of biofouling for extended periods of time in the absence of the shell (i.e., in situations where the shell can be temporarily and / or permanently removed and / or damaged).

[0112] In various embodiments, chemicals and / or compounds that affect the settlement, recruitment and / or colonization of fouling organisms on substrates can include toxins and / or biocides, as well as chemicals and / or compounds that prevent such settlement, recruitment and / or colonization, and chemicals and / or compounds that may lack positive settlement, recruitment and / or colonization cues, and chemicals and / or compounds that may produce lower levels of positive settlement, recruitment and / or colonization cues compared to those produced on surfaces within the surrounding aqueous environment and / or compared to chemicals and / or compounds that produce positive settlement, recruitment and / or colonization cues for beneficial organisms (e.g., organisms that may not generally be considered important biofouling organisms). In some embodiments, certain "welcome cues" may be absent on the protected substrate and / or associated biofilm, which may provide extended fouling protection for the substrate. In various embodiments, "welcome cues" may include nutrients and / or chemicals that micro and / or macro flora require, desire and / or promote the settlement, recruitment, colonization, growth and / or replication of a given surface, and such "deterrent cues" may include waste metabolites and / or other chemicals that can inhibit, deter and / or prevent the settlement, recruitment, colonization, growth and / or replication of micro and / or macro flora on a given surface.

[0113] It is common to distinguish between "microfouling" (often referred to as "slime"), which results from the formation of complex biofilms by single-celled microorganisms such as bacteria, diatoms, and protozoa; "soft macrofouling," which includes macroscopic algae (seaweed) and invertebrates such as soft corals, sponges, anemones, tunicates, and hydroids; and "hard macrofouling" from shelled invertebrates such as barnacles, mussels, and tube worms. Furthermore, a given biocide or biocide dosage level may often have different efficacy against juvenile and adult members of the same species, as well as different efficacy based on a number of water chemistry factors, including pH, dissolved oxygen levels, water temperature, and / or many other factors.

[0114] In various embodiments, inhibition of scaling may be represented by a reduction in total coverage of the substrate and / or one or more housing surfaces / voids by scaling organisms as compared to the total scaling coverage of a substantially similar substrate immersed and / or partially immersed in a substantially similar aquatic environment (without a protective housing). Such reduction in scaling may be a 10% reduction in scaling or more, a 15% reduction in scaling or more, a 25% reduction in scaling or more, a 30% reduction in scaling or more, a 40% reduction in scaling or more, a 50% reduction in scaling or more, a 60% reduction in scaling or more, a 70% reduction in scaling or more, a 80% reduction in scaling or more, a 90% reduction in scaling or more, a 95% reduction in scaling or more, a 98% reduction in scaling or more, a 99% reduction in scaling or more, a 99.9% reduction in scaling or more, and / or a 99.99% reduction in scaling or more. Alternatively, the inhibition of scaling on one or more protected articles can be expressed as a percentage of the amount of scaling cover and / or the mass of scaling (i.e., by volume and / or weight) formed on an equivalent unprotected substrate. For example, a protected article may form a scaling cover that is less than 10% of the unprotected substrate (e.g., where the protected substrate forms a scaling cover having a thickness of less than 0.1", and the unprotected equivalent substrate forms a scaling cover having a thickness of 1" or greater), which would reflect a reduction in scaling levels of the protected substrate and / or housing wall by more than ten times compared to the scaling levels of the unprotected substrate. In other embodiments, the protected article may form less than 1% scaling, or the scaling levels of the protected substrate and / or housing wall may be reduced by more than one hundred times. In still other embodiments, the protected article may form less than 0.1% scaling, and the protected article may have a reduction in scaling levels of the protected substrate and / or housing wall by more than one thousand times. In even other embodiments of the invention, the protected substrate and / or shell wall may have no appreciable fouling in any affected area or areas of the substrate and / or shell wall, which may represent a fouling level of 0.01% (or more) or even 0% of the protected substrate and / or shell compared to the unprotected substrate (i.e., the fouling level of the protected substrate and / or shell wall is reduced by more than ten thousand times). ASTM D6990 and the Navy Ship Technical Manual (NSTM) are known reference standards and methods for measuring the amount of fouling percentage coverage and fouling thickness on a substrate.

[0115] In various additional embodiments, inhibition of fouling can be indicated by a reduction in the total increase in coverage of both the substrate and shell surfaces by fouling organisms as compared to the total increase in fouling coverage of a substantially similar substrate (i.e., without a protective shell) submerged and / or partially submerged in a substantially similar aquatic environment, which can be measured by visual inspection, physical measurement, and / or based on the increased weight and / or volume of the combined substrate and shell (i.e., the increase in weight due to the weight of the fouling organisms attached thereto) when removed from the aqueous medium. This reduction in scaling can be a 10% reduction in scaling or more, a 15% reduction in scaling or more, a 25% reduction in scaling or more, a 30% reduction in scaling or more, a 40% reduction in scaling or more, a 50% reduction in scaling or more, a 60% reduction in scaling or more, a 70% reduction in scaling or more, a 80% reduction in scaling or more, a 90% reduction in scaling or more, a 95% reduction in scaling or more, a 98% reduction in scaling or more, a 99% reduction in scaling or more, a 99.9% reduction in scaling or more, and / or a 99.99% reduction in scaling or more.

[0116] Improved heat transfer efficiency

[0117] In various embodiments, the disclosed system can significantly improve the efficiency, function and / or durability of heat exchangers in large-scale cooling water systems. Large-scale cooling water systems are used in a variety of industrial processes, and these systems most fundamentally rely on heat transfer from a hotter fluid or gas to a cooler fluid or gas, where this heat usually travels through a "heat transfer surface", which is usually a metal wall of a heat transfer tube that separates the cold substance from the hot substance. Typically, the cooling fluid will include water, which in many cases can be salt water drawn from a bay, sea and / or ocean, fresh water drawn from a river, lake or well / aquifer, or wastewater from various sources. Some facilities utilize a cross-flow or single-pass cooling process, in which cooling water is pumped into the cooling system of the plant and used for a single pass through the heat exchanger, and the heated cooling water is then discharged to the environment, while other facilities use a cooling water recirculation system, including cooling towers, cooling ponds, air-cooled chillers (if in areas where air cooling is cost-effective) or similar heat removal equipment, attempting to extract waste heat from the heated cooling water, allowing this cooling water to return multiple times through the heat exchanger. Although recirculating cooling water systems draw less water from external sources than once-through cooling systems, recirculating systems typically still require a significant amount of "make-up" or replacement water to replace water lost through evaporation (for open recirculating systems) and "blowdown" or discharge of liquid containing concentrated dissolved solids.

[0118] In some cases, a crossflow or once-through cooling system can utilize between 20 and 40 times more water to remove the same heat load as a cooling tower system operating 5 cycles. For example, a power plant using crossflow cooling might draw 20,000 to 50,000 gallons per MWh produced, while a similar power plant using recirculating cooling might only draw 500 to 1,200 gallons per MWh. Although the water load of a crossflow plant is enormous, approximately 3,500,000 to 8,750,000 gallons per hour to power a 175MWh plant, even a recirculating plant still requires a significant amount of water, approximately 87,500 to 210,000 gallons per hour to power 175MWh.

[0119] Water is a favorable environment for many forms of life. In a single-pass cooling system, the water pumped into the cooling equipment will often breed adult and / or larval fouling organisms, many of which will seek to colonize various submerged surfaces. Even for a recirculating system with a reduced water inlet (compared to a single-pass system), any replacement or "make-up" water entering the plant will often contain many living organisms, and the flow characteristics of a recirculating cooling water system will often promote the colonization of sessile organisms to utilize the circulating supply of food, oxygen, and nutrients, and the temperature of the cooling water may become high enough to support thermophilic populations in various parts of the cooling system. These organisms will often colonize the wetted surfaces of the heat transfer tubes, which can significantly reduce the heat transfer rate of the cooling system. In many cases, even a thin biofilm formed on a heat transfer surface will significantly isolate this surface, reducing its heat transfer efficiency and greatly increasing the overall operating cost of the cooling system.

[0120]

[0121] Table 1: Increased operating costs due to biofouling

[0122] In addition to directly reducing heat transfer efficiency, biofouling often causes and / or leads to scaling and / or corrosion on wetted metal surfaces because as the biofilm thickens, less oxygen is available to the material and / or cells near the tube wall. Bacteria such as sulfate-reducing strains can produce metabolites that attack metals in a process known as microbiologically influenced corrosion (MIC). In studies conducted in the 1980s and early 1990s, the cost of cleaning, fluid handling, replacement parts, and production losses due to heat exchanger scaling were estimated to be approximately 0.25% of the GDP of all industrialized countries. For process plants, the estimated cost of repairing heat exchangers and boilers is approximately 15% of the total plant maintenance cost, with approximately half of this cost being due solely to scaling. In 2016, the World Corrosion Authority (National Association of Corrosion Engineers (NACE International)) estimated the global cost of corrosion at $2.5 trillion.

[0123] In many cooling systems, heat exchanger components are typically overdesigned by at least 70% to 80%, an amount that desirably includes compensation for the expected 30% to 50% reduction in efficiency due to fouling of the heat exchange surfaces. In addition to reducing heat transfer, fouling can also reduce the cross-sectional area of ​​the pipes or flow channels, which can increase the resistance of the cooling fluid to pass through the heat transfer surfaces. Continued reduced flow can significantly increase the pressure drop across the heat exchanger, further reducing flow rates and exacerbating heat transfer problems (including eventual plugging of the heat exchanger pipes). However, by controlling and / or improving the effects of biofouling in many of these systems, the present system allows operators to reduce this required "overdesign" to a significant level, which can result in substantial savings in capital equipment.

[0124] Similarly, biofouling in various components of recirculating cooling systems, such as cooling towers, can significantly alter flow distribution and significantly reduce evaporative cooling rates. Biofouling in these systems can also have adverse effects, such as oxygen concentrations that increase corrosion rates of the cooling system's metal walls and promote the growth and distribution of potentially deadly organisms such as Legionella, which live in amoebas.

[0125] In various embodiments, biofouling protective system embodiments are disclosed that can significantly reduce the thickness and / or extent of biofouling films formed on heat transfer surfaces of a cooling system, thereby reducing the insulating effect of biofouling and ensuring that optimal heat transfer efficiency levels are maintained within the cooling system. In some embodiments, the biofouling protective systems described herein can provide fouling protection for the entirety and / or multiple portions of a cooling system, while other embodiments can provide a "localized" or specific protection system for specific areas and / or "modules" of a cooling system, such as wetted heat transfer surfaces of one or more heat exchangers in the cooling system.

[0126] In one exemplary embodiment, the biofouling protective system may include an optional biocide-impregnated filter medium or "biocide filter" through which some or all of the cooling water flow may pass. Desirably, the filter medium may inhibit and / or "filter out" some and / or all of a variety of "larger" fouling organisms, including adult organisms of many fouling species, while the biocide in the filter medium will desirably kill, injure and / or inactivate a variety of "smaller" and / or immature fouling organisms. Such inhibition may desirably include inhibiting colonization of wetted surfaces for a limited period of time, such as the amount of time required for a target fouling organism to pass through a heat exchange tube and / or an entire cooling water system (e.g., in a single-pass cooling system). In various embodiments, the filtration and / or inhibition provided by the optional biocide-impregnated filter medium may induce the formation of a thin, minimal and / or thermally conductive biofilm on a wetted heat transfer surface, which will desirably provide an increase in heat transfer efficiency and / or the useful life of heat transfer components compared to the heat transfer efficiency / components of existing heat transfer systems that may be negatively affected by biofouling. In various alternative embodiments, the filtration and / or inhibition provided by the optional biocide-impregnated filter media can induce the formation of an easily removable or reduced biofilm on the wetted heat transfer surface that can be removed using cheaper and / or less invasive cleaning methods than existing biofilms.

[0127] In various embodiments, the biocide-impregnated filter medium will desirably inhibit the growth of biofouling on and / or within the filter medium itself, which will greatly improve the performance, service life and / or applicability of the filter medium in the disclosed system. The presence of the biocide will desirably inhibit the attachment, sedimentation and / or growth of organisms on the outer and / or inner surfaces of the filter, which can maintain the flexibility of the filter medium and significantly reduce the chance of filter tearing, tearing and / or other failures due to the presence and / or total weight increase of fouling organisms. In addition, the presence and distribution of the biocide will further desirably prevent and / or inhibit the attachment, sedimentation and / or growth of fouling organisms (especially spores, propagules, larvae and / or juveniles) in the openings and / or "pores" of the filter medium. In many cases, biocides may have very different levels of effectiveness against adult and juvenile members of the same species, where significantly higher doses of a given biocide are generally required to prevent the fouling activity of larger and / or mature organisms compared to the doses required to prevent smaller and / or juvenile organisms. By inhibiting the passage of larger organisms through the filter media and applying highly effective doses of biocide directly to smaller organisms as they pass through the biocide-coated pores of the filter media, the present system provides highly effective fouling protection without requiring highly toxic levels of biocides and / or other system components.

[0128] In various embodiments, most and / or all of the aqueous media "downstream" of the disclosed biocide filtration devices will desirably pass through one or more biocide-impregnated filter media, while in other embodiments, some portions of the fluid stream may have bypassed and / or not undergone filtration through the biocide-impregnated filter media. For example, a "skirt" or other biofouling protective device may incorporate a peripheral "wall" of the biocide-impregnated filter media, while the various openings and / or bottom of the device may be open to the surrounding environment. In such cases, biofouling is still effective against any protected substrate, as the presence of the filter media and its action may still reduce fouling of the protected substrate to some extent compared to an unprotected substrate. In a similar manner, aqueous flows of water or other liquids may benefit from partial "filtration" of the water stream through a biofouling protective device disclosed herein (i.e., which may incorporate one or more filtration units including biocide-impregnated filter media), such that filtration may desirably remove and / or inactivate larger and / or smaller fouling organisms in the filtered water stream, while a certain amount of eluted biocide in the filtered water stream will mix with the remaining unfiltered water to potentially inhibit the activity of biofouling organisms in the downstream area of ​​the filter. Such "partial filtration" filtration systems may have particular utility in circulating water streams such as cooling towers and / or the like.

[0129] Dispensing pads and filters

[0130] In various embodiments, a highly efficient device and / or system for applying and / or "dispensing" a biocide into a fluid stream to desirably inhibit the attachment, settling and / or growth of biofouling organisms within the fluid stream is disclosed. In various embodiments, a fabric filter medium is disclosed, the fabric filter medium having a top surface, a bottom surface, and a plurality of holes extending from the top surface through the fabric to the bottom surface, having a coating or "paint" containing at least one biocide or poison applied thereon. In at least one exemplary embodiment, the coating can be applied to the top surface of the fabric, wherein some portion of the coating enters and / or passes through the holes. If desired, the coating application process can include applying suction or vacuum to the bottom surface of the fabric, which can desirably draw some portion of the coating into the holes while desirably maintaining the openness (i.e., "open" state) of the hole opening through the fabric (i.e., the coating desirably does not "block" most of the holes through the fabric after being applied thereto). Once the coating is dried or otherwise cured to a desired state, the coated fabric can be formed into a desired shape and / or configuration and then placed into a water stream, wherein the fluid passes through the pores of the fabric, wherein a certain amount of the biocide and / or toxicant is eluted or otherwise distributed into the individual fluid streams passing through the pores. Because the spores, propagules, larvae and / or juvenile forms of the fouling organisms also pass through these individual pores, these organisms are exposed to relatively high doses of the biocide and / or toxicant, which desirably inactivates and / or inhibits their ability to attach, settle and / or grow within the pores of the filter medium and / or on wetted surfaces otherwise downstream in the fluid stream.

[0131] Protective systems, filter media and altered water areas

[0132] In various embodiments, the disclosed systems and / or system components will desirably alter the natural activity of biofouling organisms on a "protected" wetted surface, thereby reducing, eliminating and / or altering natural biofouling of the surface. Figure 1 An exemplary kilt or "skirt-style" enclosure system 100 is depicted, which may include separate elements of an enclosure, such as a plurality of vertically oriented "sheets" or similar structures that may be deployed into the water around an object or portion thereof, with some portion of the sheet extending downwardly below the object to be protected. If desired, the protective sheet may extend significantly below the upper edge of the skirt, object, and / or water surface, including in some embodiments to considerable depths, including 5, 10, 20, or 100 times or more the depth of the object in the water.

[0133] Figure 2 Depicted Figure 1290 (i.e., a vessel hull). In this embodiment, a vertical hull sheet or wall 200 is shown in combination with a floating support structure or boom 210 from which it is suspended downwardly into the water column. In various alternative embodiments, the disclosed hulls and / or other components may be attached directly to one or more surfaces of a protected substrate, its support structure, and / or any submerged portion thereof, while in other embodiments, the hull components may form an independent free-floating system, such as a boom boom and / or fender (i.e., free-floating between a vessel hull and a dock and / or between a vessel hull and other floating structures or around an object such as an oil rig, fixed vessel, or seawall).

[0134] Figure 3A A perspective view of an exemplary sheet or wall 300 is depicted that can be used with various systems disclosed herein. The sheet can include a fabric filter medium 310 that can be secured at a top edge to a support structure 320 that can include flexible and / or rigid support beams. One or both sides of the media 310 can include a fastening device 330, such as Velcro. TM Connect or hook and loop fasteners, or other fastening structures known in the art.The bottom edge of the media 310 may include a flexible seal or edge 340 that may act as a "soft seal" against another object and / or the bottom / sea floor of the aqueous media.

[0135] In various embodiments, a plurality of sheets 400, such as the previously described sheets, may be assembled into a peripheral ring or curtain 410 that surrounds or substantially surrounds a substrate to be protected, such as Figure 3B 4. In this embodiment, ring 410 may be completely closed, or as depicted, may be only partially closed with one or more openings along the periphery. If desired, sheet 400 may be slidably secured to support structure 420, which may allow ring 410 structure to be opened and / or closed at the periphery as desired.

[0136] Figure 3CA perspective view of an exemplary filtration module 500 is depicted, which can be used with various systems disclosed herein. The module 500 can include a fabric filter medium 510 that can be fixed to the outer edge by a support structure 520, which in this embodiment can include a flexible and / or rigid outer frame of a support beam. In addition, this embodiment desirably includes a reinforcing material 530, which is positioned on the downstream face of the medium 510 (if desired, the material can be fixed to the frame and / or fixed to the frame), such as expanded metal or wire mesh, which can strengthen and / or otherwise support the medium 510 to resist the flow force from the fluid passing therethrough. If desired, the size of the module 500 can be set and configured to fit a receiver of a filter unit, such as a fluid pipe and / or an immersion filter unit, wherein the unit optionally includes multiple filter modules (not shown). In some embodiments, if desired, the filter unit can include multiple filters in series and / or parallel with the fluid flow, including using multiple filters for a single water flow.

[0137] Figure 3D An exemplary embodiment of a free-floating enclosure 600 is depicted, wherein enclosure walls 610 may be supported by floating booms 620 that may surround or encircle a protected vessel (not shown). In various alternative embodiments, the disclosed structure and / or components thereof may be directly attached to and / or suspended directly from a dock or boat slip. For example, Fig. 7A and 7B A top view and perspective view of a U-shaped enclosure 1000 are depicted that may be positioned within a standard marine slipway 1010 with enclosure walls 1020 connected to an adjacent dock and / or other structure. If desired, a submerged and / or partially submerged door 1030, suspended curtain, or other movable wall structure may be provided proximate the stern of the vessel or other substrate to close an open "U" shaped section that may be opened and / or closed to allow a vessel to enter or exit the dock and / or enclosure. If desired, the suspended curtain may include an underwater wall of the enclosure that may rotate or swivel or pivot away from and / or toward the enclosure (i.e., in a manner similar to opening and / or closing a door) to open and / or close the enclosure to allow a vessel or other floating structure to enter and / or exit the enclosure. Alternatively, Figure 7C and 7DDepicted are side and perspective views of another U-shaped enclosure 1100 incorporating a suspended curtain closure 1110 which may include features that allow the curtain 1110 and / or portions thereof to be raised and / or lowered to allow a vessel to enter / egress from the enclosure 1100 in a typical manner (i.e., when the curtain sections are lowered a sufficient amount, the vessel may float in and / or out of the enclosure above the lowered curtain sections). As another alternative, one or more sections of enclosure wall material and / or some or all of the support structures (i.e., support ducts or wire rope supports) may "slide open" (pull up to a surface in a manner similar to opening and / or closing a shower curtain or in a manner similar to a blind configuration) to allow entry and / or exit from the enclosure - see Figure 3B .

[0138] In any of the disclosed embodiments, the upper edge of the housing wall can be suspended at least one or two feet above the water surface (with the housing desirably extending a desired degree below the water surface) so that water and / or wave action desirably does not impinge on the top of the housing wall. In various alternative embodiments, the suspended curtains and / or other structures can be mounted on a variety of surfaces, including to the protected substrate itself, a floating structure, a fixed structure, an above-water surface, an underwater surface, and / or on / in the bottom of a body of water and / or an underground harbor structure and / or the sea floor.

[0139] Figure 4A An exemplary embodiment of a skirted enclosure 700 positioned at least partially around a floating object 710 and / or other substrate is depicted, wherein a lower portion or bottom 730 of the enclosure wall 720 extends significantly below the lowest point 740 of the object 710. In this embodiment, the enclosure 700 encompasses an enclosed region of water, wherein the enclosed region is positioned within a first water layer 750 having a relatively high level of dissolved oxygen or other chemical factors, and the bottom 730 of the enclosure terminates within and / or near a second water layer 760, wherein the second layer has a significantly lower level of dissolved oxygen or other chemical factors. Desirably, this arrangement can promote the creation of a region of differentiated chemical and / or water conditions within / near the enclosure and near the floating object 710, such as an aqueous region of reduced (but not completely depleted) oxygen levels. In various embodiments, the open bottom of the enclosure can allow for a certain amount of mixing between the enclosed water and the surrounding environment, but this mixing zone 770 will desirably not significantly affect the conditions of the water region near the floating object 710.

[0140] Figure 4BAnother exemplary embodiment of a skirted enclosure 780 positioned at least partially around a floating object 785 and / or other substrate is depicted, wherein a lower portion or bottom 795 of an enclosure wall 790 extends close to and / or in contact with the bottom of a body of water and / or an underground harbor structure and / or the seafloor. In some embodiments, this can minimize mixing of the enclosure water to a desired level, although direct contact of the enclosure with the seafloor may be less desirable in situations where stronger undercurrents and / or excessive siltation may occur, or where undesirable life forms on the seafloor may invade and / or attempt to colonize enclosure components, while in other embodiments, it may be desirable to have a partial and / or complete seal of the bottom surface (i.e., natural and / or artificial surface).

[0141] In some embodiments, the disclosed enclosures will desirably provide (1) a barrier to significant levels of oxygen transmission through the enclosure sheets, (2) a potential reduction in the available energy and / or nutrient supply for biological and / or chemical reactions within the enclosure, which may reduce and / or prevent natural photosynthesis or other metabolic processes of microorganisms and / or undesirable chemical reactions within the enclosure, and / or (3) reduce and / or prevent diffusion and / or mixing of oxygen and / or other chemicals / elements into the enclosed water at the top of the enclosure. Desirably, the majority of external liquid entering the enclosure at the open and / or partially enclosed bottom will contain a lower dissolved oxygen concentration (and / or different levels of other chemical constituents) than the unprotected surface liquid level, with mixing of such water occurring primarily at depths well below the bottom of the protected item and / or hull. Once the enclosure is in the desired position, natural biological processes within the enclosure will desirably utilize most of the dissolved oxygen contained in the liquid within the enclosure, thereby significantly reducing the dissolved oxygen level within the enclosure to a level that may approach anaerobic levels, but which desirably does not exceed anaerobic levels for an extended period of time (with a certain level of dissolved oxygen supplemented through the open bottom of the structure and / or through openings and / or perforations in or between the sheet walls of the enclosure).

[0142] In various embodiments, after a period of at least 1 or 2 hours, the enclosures described herein will desirably cause the dissolved oxygen level and / or other water chemistry level of the enclosed aqueous environment (i.e., within the enclosure as compared to the dissolved oxygen level - or other water chemistry - outside the enclosure) to differ by at least 10%, at least 15%, at least 20%, at least 25%, at least 50%, at least 70%, at least 90%, or more.

[0143] In some embodiments, the vertically oriented sheets or similar structures may desirably extend to a sufficient depth in the water column to exceed the depth of the protected item and / or to reach areas of lower dissolved oxygen concentrations and / or even exceed the natural depth of the euphotic zone or thermocline, which may include depths of 1 foot, 2 feet, 3 feet, 4 feet, 5 feet, 6 feet, 7 feet, 8 feet, 9 feet, 10 feet, 11 feet, 12 feet, 13 feet, 14 feet, 15 feet, 25 feet, 50 feet, 75 feet, 100 feet, 150 feet, 200 feet, 500 feet, 1,000 feet, and / or greater depths depending on the relevant water column or other aqueous medium. Alternatively, if desired, the vertically oriented sheets or similar structures may extend to a depth near the bottom of a harbor or other bottom feature (see Figure 4B ), or may even touch the bottom of the body of water. As another alternative, the vertically oriented sheet or similar structure may extend to a depth where dissolved oxygen levels (i.e., percentage and / or absolute dissolved oxygen levels) or other water chemistry components are significantly lower than those near the surface of the water (e.g., 30%, 40%, 50%, 60%, 70%, 80%, and / or 90% or more of the dissolved oxygen or other components are reduced compared to the dissolved oxygen levels or other components of the same nearby shallower water). In various embodiments, the bottom portion of the vertically oriented sheet may include fenestrations, slits, striations, and / or perforations that may inhibit, but not completely prevent, water from flowing into and / or out of the space between the bottom of the enclosure and the seafloor.

[0144] Figure 5An exemplary embodiment of a skirt or peripheral housing placed around an offshore oil platform 810 is depicted that desirably reduces and / or eliminates biofouling of various portions of a support structure or "leg" 820 around the platform. In this embodiment, a housing wall 800 is deployed around most of the perimeter of the entire support structure and extends vertically downward into the water from a drum dispenser or "buoy" 840 (or may be secured directly to the platform and / or leg), wherein the depth of one or more of the housing walls may be increased and / or decreased as desired. Desirably, the housing wall will completely and / or partially surround the platform support (which may include surrounding a single support leg with a separate housing or the entire support structure in a single housing), and will extend to a sufficient depth to induce desired water chemistry changes in various portions of the enclosed body of water, including changes near the shallower portions and / or surface of the enclosed body of water. If desired, one or more of the housing walls may be raised or lowered as desired to induce desired water chemistry changes if such chemistry is being monitored (i.e., for example, around a drilling rig or at a remote monitoring station). In a similar manner, one or more openings, partitions, and / or sections in or between housing walls may be opened and / or closed as desired to desirably alter water chemistry in a desired manner.

[0145] In various embodiments, the housing may include features for partially and / or completely closing the bottom and / or top of the housing, which may include closable and / or openable features such as Velcro or hook and loop fastener assemblies, zippers, magnetic closures, and / or cross-stitched features. Similar types of connections may be used to connect the side edges of separate sheets together around the protected object). In at least one possible embodiment, the housing may include features that partially and / or completely "seal" some or some portions of the housing against other objects such as seawalls, hull components, larger hulls, submerged structures, and / or the bottom surface / mud of the seafloor. In other embodiments, the housing may desirably include sufficient depth to provide the biofouling protection described herein, but will be shallow enough to avoid contacting the bottom of the aqueous medium during low tide (i.e., for example, lengths of 3 feet, 6 feet, 9 feet, 12 feet, and 17 feet underwater).

[0146] It should be understood that "enclosing" and / or "partially enclosing" a substrate as described herein may also include partially enclosing a substrate with an enclosure to an extent sufficient to cause some and / or all desired water chemistry changes when in close proximity to the protected substrate, including enclosures that may not completely seal or isolate the substrate from the surrounding aqueous or other environment. For example, an enclosure protecting a hull or other submerged portion of a boat or vessel may be considered to "enclose" the hull described herein, even if the enclosure only encompasses some or all of the underwater portions of the hull and portions of the enclosure that may be open to the surrounding air (i.e., open to the "above water" environment) or to other objects such as wooden structures, rock walls, solid metal sheets, etc. In a similar manner, an enclosure having various notches, openings, seams, cracks, crevices, and / or missing wall elements therein can be considered to "enclose" a substrate as described herein, wherein there is sufficient enclosure structure to desirably cause some and / or all of the desired water chemistry changes to occur near the enclosure and / or protected substrate (wherein such chemical changes may occur naturally within the enclosure, and / or due to certain additives or modifiers that may react, absorb and / or release certain substances to artificially alter the water chemistry, or various combinations of both), thereby protecting the enclosure and / or substrate from biofouling as described herein and / or reducing the amount of biofouling of the enclosure / substrate to an acceptable level and / or causing the formation of a desired biofilm on the substrate.

[0147] In at least one exemplary embodiment, the housing may desirably include an upper surface open to the surrounding atmosphere. In this embodiment, the aqueous medium may desirably mix freely with the atmosphere and / or evaporate into the atmosphere, which may be particularly useful in evaporative cooling applications such as cooling ponds and / or cooling towers.

[0148] Figure 6Another exemplary embodiment of a biofouling protection system 900 is depicted, in which multiple housings and / or partial housings 910 can be positioned around various support struts 920 of an offshore oil drilling platform. In this embodiment, housings positioned around each of the support struts are shown, and these housings are expected to protect the support struts from biofouling as described herein. In addition, the various housings can be expected to provide some level of biofouling protection to the center drill pipe 930 (i.e., a centrally located square tube), which may not be directly protected by the housing, but the combined effect of the various modular housings positioned in discrete areas of the platform, when combined, can provide protection to areas outside the housing (i.e., a "magic cube" protection system). This design can form a "tortuous path" protective system type for a substrate, where multiple cubes, cylinders, squares and / or rectangles (or other shapes) can be segmented together to cover some or all of the support structure and / or the water below the structure, especially in situations where the structure may be too large or too widely distributed and / or the environment is not suitable for placing a single protective housing to protect the entire structure (i.e., in the North Sea). In situations where a single enclosure may not be suitable and / or feasible, it may be desirable to "break up" the enclosure into individual segments where the individual segments can be better controlled and / or even isolated to potentially allow biofouling control over a larger area encompassed by the segments (as well as potentially protecting substrates located between segments that may not be located within any segment). In some embodiments, natural and / or man-made features such as shorelines, harbor bottoms, pier walls, piers, and / or other submerged structures may form part of a tortuous or "maze-like" path in a biofouling protection system.

[0149] Fig. 8A and 8B Depicted are components of a biofouling protective system comprising a plurality of deployable "roll" sheets 1300, each roll sheet comprising a storage roll 1310 and a deployable flexible sheet 1320, wherein the flexible sheet 1320 can be deployed from the storage roll 1310 and extend downwardly (i.e., in some embodiments, desirably under the force of gravity). In various embodiments, the storage roll 1310 can include a buoyant member (e.g., a buoyant Styrofoam TMIn some embodiments, the storage roll 1310 may be attached to a support mechanism or similar structure (not shown). In various embodiments, a plurality of such deployable "roll" sheets may be provided around the periphery of the substrate 1330, with some or all of the flexible sheets deployed to form a partial and / or complete skirt or biofouling protective shell, as described herein. If desired, the various roll sheets may be deployed to a desired depth below the water surface, which may include deploying different sheets to different depths for a variety of reasons, including accommodating irregular and / or uneven bottom surfaces, to accommodate changing water conditions and / or any other reasons. If desired, the sheets may include an attachment mechanism to allow adjacent sheets to be attached to each other.

[0150] Fig. 9A Another exemplary embodiment of a biofouling protective system assembly 1400 is depicted, comprising a fabric skirt section 1410 having an upper edge that substantially surrounds and is attached around a flotation tube or float 1420. The fabric skirt section 1410 may further include a lifting handle or anchor 1430, a reinforcing strip 1435 on at least one side edge, and a sliding connector 1440. The sliding connector 1440 may desirably include a connector as known in the art for connecting to an adjacent skirt section (see Fig. 9B and 9C ) can be connected to the buoy 1420 by an appropriate connector, such as a slidable tongue in a groove arrangement. The sliding connector 1440 can also include a removable and replaceable pin or stop 1450, allowing the sliding connector to be locked in a desired position and / or preventing accidental movement of adjacent components due to wind and / or wave action. Desirably, the skirt section 1410 can further include one or more tubular fabric sections 1460, which can accommodate connectors and / or weights 1470, such as rope or chain weights positioned below the float 1420 and / or between adjacent fabric sections, which can ensure proper orientation of the components and also significantly increase the strength and / or stability of the final assembled system. In various embodiments, the skirt section can include closable flaps that provide protection for the connection to the adjacent boom section (see Fig.9D and 9E ). If desired, multiple straps, hook and loop connectors and / or Velcro may be provided. TM Straps 1480 are provided to allow fabric skirt section 1410 to be secured around float 1420 in a desired manner.

[0151] In at least one alternative embodiment, the various components of the biofouling system may be attachable to a commercially available floating boom system, such as the U.S. Marine PIG Super Swamp Boom (BOM 100) (commercially available from New Pig Corporation of Tipton, Pennsylvania, USA). In this embodiment, Fig.10 As shown, a coated fabric sheet 1500 (which may optionally be coated with a biocide-containing formulation) may be attached to an existing floating boom system 1510 via a hook-and-loop type fastener or similar arrangement, wherein the sheet 1500 includes various flaps 1520 and / or closures 1530 that desirably allow the fabric sheet to be positioned over various locations of the boom system 1510 that are currently susceptible to biofouling. In this embodiment, the fabric sheet 1500 may include a coated and / or impregnated fabric, such as the various fabric structures described herein. If desired, one or more of the fabric sheets may be removed from the boom system to allow for repair and / or replacement of individual sheets or boom sections, and then replaced to facilitate continued operation of the biofouling protective system.

[0152] Fig.11Another exemplary embodiment of a skirted enclosure is depicted that can be particularly useful as an anti-biofouling and / or filtration system for systems that use seawater and / or fresh water as a cooling water source. In this embodiment, a floating enclosure 1600 or "reservoir" in an aqueous environment 1610 is provided, wherein the enclosure has one or more peripheral walls 1620 that can contain significantly more aqueous fluid than the amount required by the cooling system on a normal use basis. For example, if the cooling system requires 1000 gallons of water per minute during normal operation, the reservoir can desirably contain at least 10,000 gallons, at least 20,000 gallons, at least 50,000 gallons, at least 100,000 gallons, at least 500,000 gallons, and / or at least 1,000,000 gallons and / or more water. If desired, an optional top cover 1630 can be provided to isolate the enclosed water from the atmosphere, such as by using a flexible non-permeable membrane or plastic tarpaulin material. The water inlet 1640 can be located near the top center of the reservoir, where the inlet is supported by a float 1650 or other support, with a connected flexible or rigid water tube 1660 carrying water (which can have a relatively low - but preferably not anoxic - dissolved oxygen level or other desired water chemistry factor level in various embodiments) drawn from the inlet 1640 for transfer to the cooling device or other use. Desirably, water with a relatively high dissolved oxygen level can enter the reservoir through the bottom 1670 and / or any side openings or gaps of the reservoir. During the time it takes for water molecules to be transported up and / or across the water column in the reservoir, natural and / or artificial deoxygenators in the water column will desirably reduce the dissolved oxygen level in the water (as depicted by the gradient arrows 1680) so that the dissolved oxygen level is depleted before entering the inlet. However, in at least one alternative embodiment, the water inlet can be near the bottom of the housing and / or the bottom surface of the reservoir, and the water inlet is typically the coldest water in the housing / reservoir for use by the cooling device.

[0153] As previously noted, at least one exemplary embodiment includes a method for determining an appropriate design, size, shape, and / or other features of an enclosure that can be used to determine a recommended minimum enclosed volume and / or water exchange rate to desirably reduce and / or eliminate biofouling within the enclosure. In some embodiments, such as in a membrane filter configuration, where the enclosure can be utilized to provide a cooling water source and / or other source of water to a manufacturing plant (i.e., a power plant, desalination plant, refinery, and / or other manufacturing plant), the disclosed method can potentially be used to reduce and / or eliminate biofouling within the plant's water and / or other conduits, and in some embodiments, no additional filtering and / or microfiltration of the water is required.

[0154] Fig. 12A and 12BAnother exemplary embodiment of an enclosure 1700 is depicted that can be used to reduce biofouling and facilitate utilization of seawater, freshwater, brackish water, or some other aqueous liquid by a manufacturing plant, power plant, or some other facility. In this embodiment, the enclosure 1700 can be positioned within a body of water and can even be fully submerged within the aqueous environment (i.e., an underwater "balcony") to a depth "D", such as Fig. 12A The housing may include one or more replaceable impregnated fabric filter media 1710 on one or more exterior surfaces, wherein a suction tube or other inlet device 1720 is positioned within the housing 1700, and as water is drawn into the suction device, a replacement water flow may enter the housing through the media 1710 and / or any other openings and / or perforations in and / or between the housing walls (which may include the ceiling, side walls, and / or floor surfaces of the housing).

[0155] In some embodiments, the volume of the housing may be large enough to contain a substantial liquid reservoir such that the liquid may be retained within the housing for a desired "residence time" to allow desired water chemistry changes to occur to reduce and / or eliminate biofouling occurring within the water piping of the housing and / or facility. In some other embodiments, the volume of the housing may be smaller and may not contain a significantly large liquid reservoir (compared to the expected flow rate into the inlet during use), in which embodiments, the liquid may not be retained within the housing for a desired "residence time" to allow desired water chemistry changes, but may rely primarily on filtration and / or optional biocide application through the filtration media to desirably reduce and / or eliminate biofouling occurring within the water piping and / or heat transfer surfaces of the housing and / or facility.

[0156] In various desired embodiments, a fully submerged enclosure may be particularly useful in situations where the enclosure retains and / or draws water from a lower or lowest point within a water column, which water may be cooler water (i.e., for use as industrial cooling water) and / or the water body may contain lower and / or minimal levels of dissolved oxygen (or other desired water chemistry factors).

[0157] In various embodiments, the shell design may desirably contain a volume of water equal to or exceeding the daily (i.e., 24-hour) water consumption of the facility. For example, if the facility utilizes 100,000 gallons of cooling water per hour over a 24-hour period, a preferred shell design will contain at least 2.4 million gallons of water. Assuming that 1 cubic foot of seawater contains approximately 7.48 gallons, a preferred shell design may contain approximately 321,000 cubic feet, which may be a shell containing a volume of approximately 113 feet wide, 113 feet long, and 26 feet high (i.e., 331,994 cubic feet). In other preferred embodiments, the volume of water contained may be sufficient to supply at least 8 hours of water, while other preferred embodiments may provide 2 or more days of water. The water desirably present in the shell will desirably be granted sufficient "residence" time to change the water chemistry in a desired manner (as previously disclosed) so as to produce a certain type of "adjusted" water, which may include a situation where the entire water demand of a given device can be provided by the "adjusted" water, and a situation where the "adjusted" water can only provide a portion of the water demand of a given device.

[0158] In some alternative embodiments, it may be desirable to modify an existing body of water to include various features of the housing of the present invention, such as utilizing a natural or artificial water source to provide cooling water and / or water for some other industrial process. For example, energy generation facilities often utilize 300,000 to 500,000 gallons of water (or more) per minute to cool generator sets, while a typical large refinery may utilize 350,000 to 400,000 gallons per minute. In such cases, it may be uneconomical, practical, and / or undesirable to construct a single housing or series of housings containing a full day's worth of water. Instead, various embodiments incorporating the "partial" housings and / or housing components (i.e., vertical sheets and / or skirts) described herein can be used to create a tortuous path for water within an existing natural and / or artificial reservoir to condition the water to meet a desired water chemistry level, and may include features that expose the surface of the flowing water to the atmosphere to promote evaporative cooling of the reservoir and / or turbulent mixing of water along a tortuous flow path.

[0159] Fig.13A A simplified perspective view of an exemplary embodiment of a natural or artificial reservoir or pond 1800 is depicted, which can include a water source for cross-flow cooling as well as a recirculating water reservoir or "cooling pond" often used in recirculating cooling systems. Fig. 13B and 13CAs best seen in , the biofouling protection system can include a plurality of housing walls 1810 positioned within the pond 1800 to desirably create a labyrinthine or tortuous path for an aqueous liquid within the body of water, such as by positioning a series of alternating walls 1810 within a basin, pond, or harbor that alters the natural form of the fluid toward an inlet 1820. In this embodiment, the walls 1810 can desirably redirect the liquid along one or more desired paths, thereby potentially increasing the effective length and / or shape of the desired water "path," which can allow the water to be "conditioned" in a desired manner to obtain various of the improvements disclosed herein. For example, water passing through such tortuous paths can be granted sufficient "residence" time to change the water chemistry in a desired manner so as to produce a certain type of "conditioned" water, which can include situations where the entire water demand of a given device can be provided by the "conditioned" water, as well as situations where the "conditioned" water can only provide a portion of the water demand of a given device. If desired, the present invention can treat different water "streams" in different manners, such as in Fig. 13C In an embodiment wherein a first water stream 1850 passes through the entire maze to inlet 1820, a second water stream 1860 is added to the maze at a location where it only passes halfway through the maze to inlet 1820. Such an arrangement may include water from different sources that is added directly to the conditioned water within the housing.

[0160] Fig.13D Another alternative arrangement of a labyrinth path is shown in , in which a series of circular housings are employed to form a tortuous path towards the centre of the reservoir where the inlet 1820 is located, from which water can then be removed from the path as previously described.

[0161] If desired, the housing and / or other system design may incorporate one or more flow paths for the aqueous fluid that gradually increase in width and / or volume, with increasing cross-section as the water flows near an inlet, which may be a particularly useful design feature in natural reservoirs and / or artificial tributaries or rivers, providing additional residence time and / or more surface area for the flowing water.

[0162] Fig. 22A perspective view of another exemplary embodiment of an enclosure 2200 for protecting a substrate from biofouling is depicted, the enclosure incorporating a wall structure having multiple layers, which may include a wall structure incorporating multiple layers having the same, similar, or different permeabilities in each layer, having the same, similar, or different materials in each layer, and / or having the same, similar, or different thicknesses in each layer. In another embodiment, the layers may be spaced apart with minimal or no distance between each layer or a significant distance between each layer. If desired, the first cover layer 2210 may be removable, wherein removal of the first cover layer (which may include a "tear-off" or other type of connection section 2215) exposes an intact second lower layer 2220, and removal of the second lower layer exposes an intact third lower layer (not shown), etc., all surrounding the protected substrate. If desired, the first cover layer can be removable, wherein the remaining one or more lower layers remain intact around the substrate, and a replacement first cover layer can then be positioned around the intact one or more lower layers and / or substrate, such as where the first cover layer may become sufficiently fouled to justify removal and / or replacement. Alternatively, the multiple upper and / or lower layers can include multiple sacrificial layers, each of which is removed as it becomes sufficiently fouled, thereby exposing the original or semi-original layer below (i.e., still surrounding and protecting the substrate). In some embodiments, the lower layer can remain in place around the substrate for an extended period of time, even 1, 2, 3, 4 and / or 5 years or more, and the substrate and / or the outer layer around the one or more lower layers as previously described are periodically removed, replaced and / or refreshed (i.e., the fouled layer is removed and replaced with a new cover layer immediately and / or delayed). If desired, such a system can be applied in salt water, fresh water and / or brackish water.

[0163] Fig.23An exemplary embodiment of an aqueous flow mechanism of a supplemental pumping system 2300 for adding and / or removing aqueous liquids and / or other materials or substances from a closed environment within a housing 2310 is depicted. In this embodiment, the housing comprises an outer wall or boundary, which in some embodiments may include one or more permeable walls, and in other embodiments may include one or more semi-permeable and / or non-permeable walls (which in some embodiments may include some or all of the walls of the housing being impermeable). A pumping mechanism 2320 having a flow cavity or inlet 2330 and an inlet tube 2340 may be provided, wherein the pump further comprises an outlet 2360 and an outlet tube or flow cavity or flow path tube 2370 extending from the outlet of the pump through at least one wall of the housing and through / into the aqueous environment within the housing. In various embodiments, at least some flow cavity portion 2380 of the outlet tube may extend a distance within the housing, wherein the outlet may be positioned proximate and / or distal to a protected substrate (not shown) and / or one or more housing walls of the housing. During use, the pumping mechanism can be activated to supply external water into the housing in a desired manner, and / or the pump operation can be reversed to draw water from the housing to release it into the environment outside the housing. Alternatively, the pumping mechanism can be used to supply additional oxygen or other water chemical factors to the closed environment. If desired, some or all of the pumping mechanism and / or flow chamber and / or inlet 2330 can be positioned in the housing, or alternatively in a certain part of the housing wall and / or through the certain part, or can be positioned outside the housing if desired. In one embodiment, the aqueous flow mechanism can be a propeller system, a petal system, a flow conduit, a flow channel or a flow tunnel that can be used to move water or produce desired flow characteristics in a manner similar to a pump system.

[0164] In various embodiments, the enclosure design can incorporate various configurations of permeable walls, including (1) an enclosure that completely encloses the substrate (i.e., a "box" or "flexible bag" enclosure), (2) an enclosure having side walls surrounding the periphery of the substrate (i.e., a "skirt" or "overhang" that encloses the sides of the substrate but may have an open top and / or bottom), (3) an enclosure formed from modular walls that can be assembled around a substrate, which modular walls may incorporate various openings and / or missing modular sections (i.e., an "open geodesic dome" enclosure), (4) an enclosure that only surrounds an immersed portion of the substrate (i.e., a "floating bag" enclosure with an open top) and / or (5) an enclosure that only protects a single side of the substrate (i.e., an "overhang" enclosure), as well as many other possible enclosure designs. Additionally, the housing wall may be relatively smooth or flat or curved and / or continuous, or, if desired, the housing wall may include a more complex structure, such as an undulating surface, a corrugated or accordion-shaped surface, a folded, "corrugated" or "crimped" surface, and / or other features that may significantly increase the surface area and / or potentially alter the filtering capabilities of the housing wall.

[0165] In various embodiments, the housing can incorporate one or more walls comprising a three-dimensional flexible filter fabric comprising fiber filaments and having an average base filament diameter of about 6 mils or less (i.e., 0.1524 mm or less). In various alternative embodiments, the housing material can include a deformed polyester. In addition, natural fiber materials (such as 80×80 burlap) may also be useful for protecting a substrate as a housing material, even though the natural material degrades relatively quickly in an aqueous environment, and the potential degradation process also results in significant measurable pH differences within the housing, which may be useful in various aqueous environments. If desired, various housing embodiments can incorporate degradable and / or hydrolyzable materials and / or connections (i.e., between components and / or along polymer chains of component materials) that allow the housing components to degrade in an aqueous medium after a certain period of time.

[0166] In various embodiments, the devices of the present invention will desirably provide for reducing, stopping and / or reversing biofouling and / or creating a desired enclosed environment that prevents the settlement of biofouling organisms and / or facilitates the formation of a desired antifouling layer and / or biofilm on a substrate - when deployed to affect the formation of a favorable biofilm, a desired local aquatic environment (i.e., a "differentiated environment") is created, which results in reduced biofouling on the protected substrate or article. In various embodiments, this "differentiated environment" can be created within minutes or hours of the deployment of the enclosure around the substrate, while in other embodiments, it may take days, weeks, or even months to create the desired "differentiated environment." If desired, the enclosure can be deployed long before the substrate is placed therein, while in other embodiments, the enclosure can be deployed simultaneously with the substrate, or the enclosure can be deployed long after the substrate is submerged and / or maintained in the aqueous environment. In various embodiments, significant water chemistry differences and / or other unique aspects of the differentiated environment may be generated beginning immediately after deployment or may be generated within 1 hour of placing the housing in an aqueous environment (which may include placing the housing alone in the environment and / or in proximity to the substrate to be protected), while in other embodiments, initiating and / or generating the desired differentiated environment (which may include generating a complete differentiated environment as well as generating various scale inhibition conditions that may be altered and / or supplemented with the introduction of additional aspects of the differentiated environment) may require the housing to be in place around the substrate for at least 2 hours, at least 3 hours, at least 6 hours, at least 12 hours, at least 18 hours, at least 1 day, at least 2 days, at least 3 days, at least 4 days, at least 5 days, at least 6 days, at least 1 week, at least 2 weeks, at least 3 weeks, at least 4 weeks, at least one month, at least 2 months, at least 3 months and / or at least 6 months or more. In various embodiments, the various water chemistry differences that may occur during these different time periods may include dissolved oxygen, pH, total dissolved nitrogen, ammonium, ammoniacal nitrogen, nitrate, nitrite, orthophosphate, total dissolved phosphate, silica, salinity, temperature, turbidity, chlorophyll, etc., and the various concentrations of the water chemistry differences may increase and / or decrease at different times, including different concentrations of individual components at different shell immersion durations.

[0167] In some cases, after a certain period of time, the device of the present invention and / or its components may degrade and / or no longer provide the desired level of antifouling and / or environmental generation effect. In various embodiments, the time until the shell loses its antifouling effect may vary based on a variety of factors (including the specific aquatic environment, season, temperature, marine biological composition present, temperature, light, salinity, wind, water speed, etc.). It should be noted that based on the conditions of the aquatic environment, the shell may temporarily lose its antifouling and / or environmental generation effect, only to restore one or more of its antifouling / environmental generation effects when the conditions return to normal or reach a certain desired measurement. As used herein, "service life" can mean the amount of time from the deployment of the shell to the time when the macroscopic fouling level on the substrate becomes a problem, while "shell life" can mean the amount of time that the shell itself is physically intact and effective around the substrate itself (the shell life may be exceeded by the "service life" of the biofouling protection provided by the shell). In various aspects of the present invention, one or both of the service life of the shell and / or the shell life can be: not less than 3 days, not less than 7 days, not less than 15 days, not less than 30 days, not less than 60 days, not less than 90 days, not less than 120 days, not less than 150 days, not less than 180 days, not less than 270 days, not less than 1 year, not less than 1.5 years, not less than 2 years, not less than 3 years, not less than 4 years or not less than 5 years.

[0168] If desired, the shell or its portion can be optionally made of degradable materials and / or can incorporate degradable attachments and / or closures, the degradable materials can include biodegradable, photodegradable, oxidizable and / or hydrolyzable materials, which desirably result in a decrease in molecular weight, quality and / or strength or durability of the shell or its portion over time under certain conditions (as well as other potential effects). In various embodiments, the continued exposure of such materials to an aquatic environment may ultimately result in the shell (or one or more layers thereof) being separated from the substrate and / or the environmentally friendly degradation of the shell and / or its various components. Such separation can include separating the entire shell and / or separating different layers in a manner that is released over time and / or by a degree of fouling (i.e., based on weight, based on resistance and / or reduced wall flexibility).

[0169] Regardless of which type of material is used, the housing can be optionally constructed so that the structure can be shaped to be expandable in three dimensions, radially, longitudinally, and / or various combinations thereof. If desired, this type of construction will desirably allow positioning on and / or around an object in a variety of configurations, which can include positioning so that the housing walls can mirror the contour of the surface of the object to which the object is attached. In some embodiments, the housing can be formed in a mirror shape of one or more surfaces of the substrate and is typically at least slightly larger in size to accommodate the substrate therein.

[0170] In some exemplary embodiments, the housing may be constructed of entirely natural materials (e.g., burlap or hemp) and may be deployed to protect substrates in particularly sensitive waters (e.g., drinking water reservoirs and / or wildlife sanctuaries) where the use of artificial materials and / or germicidal toxins is prohibited and / or prevented. In such cases, even if the housing becomes detached from the substrate and / or associated support structure (because one or more additional openings in the detached structure may now prevent the development of a protected aqueous environment and its attendant advantages), the housing will desirably provide protection for the underlying substrate for a desired period of time without creating a significant potential for contaminating the water and / or harming the local aquatic environment. In such cases, once the substrate no longer requires protection, or the housing becomes fouled and / or damaged for a variety of reasons, the housing may be removed and / or replaced with a new housing and / or housing assembly of similar material, wherein fouling protection is restored to the substrate as desired.

[0171] Filter Media and Fabrics

[0172] In various embodiments, a variety of fabrics and / or other filter media are described that can be incorporated into some or all of the fouling protective systems described herein. In many of these embodiments, a coating or paint can be incorporated into the fabric, wherein the coating or paint contains one or more biocidal and / or biotoxic substances that can be released and / or eluted into a fluid flowing through the fabric and / or its pores.

[0173] Fig.14A An exemplary scanning electron microscope (SEM) micrograph of an exemplary spun yarn 1900 is depicted, depicting a central body or yarn bundle 1910 of entangled filaments 1920 with individual filament ends 1930 extending transversely relative to the central body 1910. Fig. 14B A cross section of a central body 1910 is depicted, highlighting the very fine size of the individual filaments 1920 within the yarn bundle 1910. As shown in FIG. 1 , an enlarged view of a knitted fabric 1950 comprising PET spun yarn is depicted. Fig. 14C As best seen in FIG. 1 , a series of gaps or openings 1980 are positioned between the yarn bundles 1970 during the weaving process, with one or more extended fibers or fiber ends 1990 extending across each opening (with multiple fiber ends desirably traversing each opening in various embodiments).

[0174] In various embodiments, the housing wall and the protected substrate therein may be separated and / or spaced apart by an average spacing (i.e., between the inner wall of the housing and the outer surface of the substrate) of about 200 inches, about 150 inches, or about 144 inches, or about 72 inches or less, or about 36 inches or less, or about 24 inches or less, or about 12 inches or less, or about 6 inches or less, or about 1 inch or less, or about 1 inch or more, or 6 inches or more, or about 1 inch to about 24 inches, or about 2 inches to about 24 inches, or about 4 inches to about 24 inches, or about 6 inches to about 24 inches, or about 12 inches to about 24 inches, or about 1 inch to about 12 inches, about 2 inches to about 12 inches, or about 4 inches to about 12 inches, or about 6 inches to about 12 inches, or about 1 inch to about 6 inches, or about 2 inches to about 6 inches and / or about 4 inches to about 6 inches. In various alternative embodiments, at least a portion or all of the housing may be in direct contact with the substrate in one or more areas (including but not limited to enclosed portions of the housing), and thus in some embodiments there may be substantially little or no distance between the structure and the substrate.

[0175] In various other embodiments, it may be desirable for the spacing between the shell wall and the substrate to fall within a certain average distance range, or the desired spacing may be proportional to the width, length, depth, and / or other characteristics of the shell and / or the substrate to be protected. For example, maintaining a predetermined spacing between a smaller substrate and a smaller shell containing only a few gallons of water may be more critical than the spacing between a relatively large ship hull and a large shell containing thousands or millions of gallons of water in its "differentiated environment" within the shell, especially in the presence of relatively small amounts of water in a differentiated environment that may be more susceptible to changes in water exchange levels and resulting water chemistry relative thereto. In such cases, the desired spacing between the shell wall and the opposing surface of the substrate may be 2% or less of the distance between the opposing shell walls, or 5% or less, or 10% or less, or 20% or less, or 30% or less, or 40% or as much as 49.9% of the distance between the opposing shell walls, depending on substrate size, type, shell design, and / or shell rigidity and / or design. In another embodiment, the localized aqueous environment can extend a distance of 100 inches or more, 50 inches or more, 10 inches or more, 5 inches or more, 3 inches or more, 2 inches or more, 1 inch or more, 0.5 inches or more, 0.1 inches or more, 0.04 inches or more, 50 feet or less, 40 feet or less, 20 feet or less, 20 feet or less, 10 feet or less, 4 feet or less, 2 feet or less, 100 inches or less, 10 inches or less, 5 inches or less, 1 inch or less, 0.1 inches or less, 0.04 inches or less from the surface of the substrate.

[0176] Fig.15A An exemplary fabric material 2000 in the form of a rolled sheet is depicted, which can be used in various ways to form various housings and / or filter elements described herein. In this embodiment, the material desirably includes a flexible fiber material, in this case a fabric material, which can include woven, knitted, felted, nonwoven and / or other structures of natural fiber cloth and polyester or other synthetic fibers and / or various combinations thereof. In various embodiments, the fabric can be used to construct the various housing embodiments described herein, and / or it may be possible and / or desirable to wrap or otherwise "cover" an elongated substrate with such a rolled sheet material, particularly in cases where the unrolled and wrapped sheet may overlap with other sheet sections (i.e., along a pile or support beam), which other sheet sections can produce an "enclosure" including a gradually wrapped substrate, wherein the fabric material is wrapped around the substrate in overlapping "spiral stripes" or a maypole-type technique or the inner wall lining of a water tank or irrigation pipe. In such cases, it may be desirable for the fabric to be in direct contact with the protected substrate, with the very thin layer of liquid between the fabric shell wall and the substrate surface (and optionally liquid within the fabric itself) constituting a "differentiated environment" as described herein.

[0177] Fig. 15B Another exemplary embodiment of a rolled sheet fabric 2005 is depicted that incorporates adhesive, hook and loop fastener material 2010 (and / or sewn seams) along various portions of the fabric that may desirably self-adhere to other fabric portions and / or other devices and / or components, wherein a majority of the fabric includes perforated or permeable portions 2020 as described herein (and in various embodiments, the fastener material itself may also include permeable and / or impermeable portions). If desired, the material flap covering some other fabric portion may be impermeable and protect the underlying structure.

[0178] In use, the fabric may be wrapped around a pile or supporting beam or other structure to form an enclosure around a portion of the pile, which may include a progressive wrapping method (i.e., a "spiral rib" type wrap) or an annular wrapping method (i.e., a "loop" type wrap) to produce various enclosures that function similarly to those described herein to protect various portions of the pile from biofouling organisms and / or other degradation. In various embodiments, attachment using hook and loop or similar fasteners is particularly desirable because such fastening techniques can be made permeable and allow water exchange therethrough in a manner similar to the various permeable materials described herein.

[0179] If desired, the shell can be constructed using separate component segments that can be assembled into a three-dimensional (3D) construct. For example, separate wall segments of the shell can be arranged to be attached to each other in various configurations (comprising triangles, squares and / or other polygons). If desired, the wall segments can be supported by a relatively rigid chassis, or the segments can be highly flexible and / or arranged on rollers or other carriers, which can be unfolded to release each individual segment before assembly. In at least one alternative embodiment, an open shell frame or support can be provided, wherein an elongated sheet or shell wall material that can be wrapped around and / or covered on the frame segment is provided (and, for example, applied to the frame in a manner similar to taping or a "ship wrap" object to be shipped by a common carrier).

[0180] In various alternative embodiments, the shell and / or its constituent materials may include a three-dimensional fabric matrix and / or fiber matrix structure, which is formed by interlaced and / or entangled wire strands formed by a grid-like, net-like, mat-like or porous fabric arrangement, and the three-dimensional fabric matrix and / or fiber matrix structure may be combined with one or more non-flat and / or non-smooth fabric layers in various embodiments. In a very simplified form, the shell may contain multiple horizontally positioned elements (and various combinations of other fiber elements arranged in different directions) interlaced with multiple vertically positioned elements, and the shell may include multiple separated and / or interlaced layers. The flexible material may include one or more spaced apart layers that may include baffles or various interconnected sections. Desirably, each yarn or one or more other wire elements in the shell material will include a preselected number of individual strands, wherein at least a portion of the strands extend outwardly from the wire core element at different positions and / or directions, thereby generating a three-dimensional tortuous network of interlaced wires and wire strands in the fabric. In various embodiments, the various elements of the fibrous matrix can be arranged in virtually any orientation (including diagonal lines), or arranged in a manner parallel to each other so as to form a right angle, or arranged in virtually any other orientation, including a three-dimensional orientation and / or a random distribution (i.e., a felt pad) and / or pattern. In addition, although in some embodiments, there may be significant spacing between individual elements, in other embodiments, the spacing can be reduced to a tighter pattern so as to form a tight pattern with little or no spacing between each other. In various preferred embodiments, elements such as threads and / or fibers can be made of natural or synthetic polymers, but can be made of other materials such as metal, nylon, cotton, or combinations thereof.

[0181] Various aspects of the invention may include the use of a highly ciliated fiber matrix and / or flexible material, meaning that the material may include tendrils or hair-like appendages (i.e., fibers) that protrude from its surface or enter the pores or open spaces of a 3D flexible fabric, thereby creating a "filter" medium. The tendrils or hair-like appendages may be part of or incorporated into the material that makes up the three-dimensional flexible filter material. Alternatively, the tendrils or hair-like appendages may be formed from a separate composition that is adhered or attached to the flexible material. For example, the tendrils or hair-like appendages may be attached to and protrude from an adhesive layer that is itself attached to the surface of the flexible material. In various aspects of the invention, the tendrils or hair-like appendages may protrude from the surface of the shell material, while in other aspects, the tendrils or hair-like appendages may extend inwardly from the shell material and / or extend inwardly toward and / or into other lines and / or fibers of the shell material fiber matrix and / or fabric. In various aspects of the invention, the tendrils or hair-like appendages may be elastic and / or may vibrate and / or sway due to the movement of the shell and / or water. In various embodiments, a combination of the movement of the cilia themselves and / or the tendrils or hair-like appendages may also prevent the settlement of biofouling organisms on or in the surface of the enclosure.

[0182] In various embodiments, the presence of many small fibers in the permeable material of the shell can greatly increase the complexity of the 3-dimensional structure of the material, because these structures can extend into and / or around the open gaps in the woven fabric pattern. This arrangement of fibers can further provide a more tortuous path for organisms attempting to penetrate the depth of the fabric and enter the internal environment protected by the shell (i.e., increasing the "filtering" effect of the material) and / or can provide a higher surface area of ​​the fabric on which the optional biocide coating can be adhered. In various embodiments, it has been determined that spun polyester has very desirable properties as a shell material because the shape and / or size of the three-dimensional "entry paths" into the shell (i.e., when microorganisms pass through the openings and / or holes of the material) will desirably provide longer paths, larger surface areas and / or can prove to be more effective in filtering and / or preventing fouling organisms from flowing into the shell and / or retaining a larger amount of biocide coating therein.

[0183] In various embodiments, the three-dimensional topography of the shell wall will desirably contribute to the anti-biofouling effect of the shell, as such fabric construction can increase the "filtration effect" of the shell wall and / or may negatively impact the ability of various fouling organisms to "latch onto the shell fabric and / or protected substrate." However, in other embodiments, the shell wall and / or other components can include "flatter" and / or "smoother" materials, such as textured yarns or other materials (and / or other material construction techniques), and still provide many of the anti-biofouling effects disclosed herein. Although such materials can be significantly flatter, smoother, and / or less fimbriae than materials incorporating spun polyester yarns, these materials can still provide acceptable levels of biofouling protection for various applications.

[0184] The various materials that may be suitable for constructing the shell to varying degrees include various natural and synthetic materials, or combinations thereof. For example, burlap, jute, canvas, wool, cellulose, silk, cotton, hemp and muslin are non-limiting examples of possible useful natural materials. Useful synthetic materials may include but are not limited to the polymer classes of polyolefins (such as polyethylene, ultra-high molecular weight polyethylene, polypropylene, copolymers, etc.), polyesters, nylons, polyurethanes, rayon, polyamides, polyacrylates and epoxy resins. Various types of glass fiber compositions may also be used. The combination of polymers and copolymers may also be available. These three-dimensional flexible materials may be formed into textile structures, permeable sheets or provide other configurations that can provide structures of antifouling and / or filtering properties as described herein. The example of the potential suitable flexible material for constructing the shell described herein includes but is not limited to burlap, canvas, cotton fabric, linen, muslin, permeable polymer sheets, fabrics constructed of polymer fibers or filaments, and permeable films and membranes. In various aspects of the invention, the flexible material can be selected from natural or synthetic fabrics such as burlap, knitted polyester or other fabrics, woven polyester or other fabrics, spun polyester or other fabrics, various combinations thereof, or other fabrics having various properties, including those disclosed herein.

[0185] In various embodiments, the flexible material forming one or more walls of the shell can have a structure formed by entangled fibers or fiber bundles (that is, yarn). As used herein, "entanglement" means that the fiber can be nonwoven, woven, braided, knitted or otherwise mixed to produce a fiber matrix that can have various filtrations described herein and / or water permeability and / or water exchange characteristics. The material that the fibers are entangled together can desirably produce a pattern of open space and closed space in a three-dimensional flexible material, wherein the open space defines a gap. Desirably, the fiber that can constitute the flexible material is a combination of, for example, a single filament, a plurality of filament bundles, a filament of a natural or synthetic composition or a natural and synthetic composition. In various aspects of the invention, the fibers have an average diameter (or "average filament diameter") of about 50 mils or less, about 25 mils or less, about 10 mils or less, about 6 mils or less, about 5 mils or less, about 4 mils or less, about 3 mils or less, about 2 mils or less, about 1 mil or less, about 0.5 mil or less, about 0.4 mil or less, about 0.3 mil or less, about 0.2 mil or less, or about 0.1 mil or less.

[0186] In some aspects of the invention, the flexible material may include a woven or knitted fabric. For example, the weft per inch ("ppi" or weft per inch) of the woven fabric is about 3 to about 150, about 5 to about 100, about 10 to about 50, about 15 to about 25, about 20 to about 40, and / or about 20 ppi. In other aspects of the invention, the warp per inch ("epi" or warp per inch) of the woven fabric is about 3 to about 150, about 5 to about 100, about 10 to about 50, about 15 to about 25, about 20 to about 40, and / or about 20 epi or about 24 epi. In still other various other aspects of the invention, the courses per inch ("cpi") of the knitted fabric may be about 3 to about 120, about 5 to about 100, about 10 to about 50, about 15 to about 25, about 20 to about 40, and / or about 36 cpi or about 37 cpi. In even other aspects of the invention, the knit fabric has a wale per inch ("wpi") of about 3 to about 80, about 5 to about 60, about 10 to about 50, about 15 to about 25, about 20 to about 40, and / or about 36 wpi or about 33.7 wpi.

[0187] Thus, in at least one aspect of the invention, the yarn size density (i.e., weft yarns multiplied by warp yarns per unit area) of the woven fabric is from about 9 to about 22,500, from about 100 to about 20,000, from about 500 to about 15,000, from about 1,000 to about 10,000, from about 2,500 to about 8,000, from about 4,000 to about 6,000, from about 2,500 to about 4,000, from about 5,000 to about 15,000, from about 10,000 to about 20,000, from about 8,000 to about 25,000, from about 20 to about 100, from about 30 to about 50, about 45, or about 40 yarns per square inch.

[0188] In another aspect of the invention, the yarn size of the woven or knitted fabric can be about 40 denier to 70 denier, about 40 denier to 100 denier, about 100 denier to about 3000 denier, about 500 denier to about 2500 denier, about 1000 to about 2250 denier, about 1100 denier, about 2150 denier or about 2200 denier.

[0189] In still another aspect of the invention, the basis weight per unit area of ​​the woven or knitted fabric can be about 1 to about 24 ounces per square yard (about 34 to about 814 g / m2), about 1 to about 15 ounces per square yard, about 2 to about 20 ounces per square yard (about 68 to about 678 g / m2), about 10 to about 16 ounces per square yard (about 339 to about 542 g / m2), about 12 ounces per square yard (about 407 g / m2), or about 7 ounces per square yard (about 237 g / m2), or about 3 ounces per square yard. In another aspect of the invention, a desired woven fabric based on spun polyester fibers can be used as a shell material, wherein the basis weight of the fabric (including the weight of the base fabric before any coating or modification) is about 410 grams per square meter (see Table 3).

[0190] In various exemplary embodiments, suitable shell or structural wall thicknesses may range from 0.025 inches to 0.0575 inches or greater, with desirable shells being approximately 0.0205 inches thick, approximately 0.0319 inches thick, approximately 0.0482 inches thick, and / or approximately 0.0571 inches thick. Shells having thicknesses greater than and / or less than the specifically described thicknesses may be used in a variety of shell designs and various shell materials with varying degrees of success, depending on the desired substrate or particular application to be protected, in various alternative embodiments, the flexible base materials, fibers, and / or strands used in the construction of the disclosed fiber matrix may have a wide variation in thickness and / or length, depending on the desired substrate or particular application to be protected. For example, in some aspects of the invention, the thickness of the flexible material can be about 0.001 to about 0.5 inches, about 0.005 to about 0.25 inches, about 0.01 to about 0.1 inches, about 0.02 inches, about 0.03 inches, about 0.04 inches, about 0.05 inches, or about 0.06 inches. Variations in thickness and permeability are contemplated within a single structure, such as a membrane filtration structure, and multiple layers thereof.

[0191] It should be understood that a variety of materials and / or material combinations can be used as shell materials to achieve the various purposes described herein. For example, a film or similar material can be used as an alternative to a fabric shell wall material, which can include permeable and / or impermeable films in some or all of the shell walls. Similarly, natural and synthetic materials such as rubber, latex, thin metals, metal films and / or foils and / or plastics or ceramics can be utilized, with varying results.

[0192] In various embodiments, it is desirable to use "permeability" as a metric for some aspects of the enclosure and / or its components because it may be somewhat difficult to measure and / or determine the "effective" porosity of openings throughout the polymeric textile and / or burlap material due to the "fuzziness" and / or randomness in the architecture of such fabrics, which permeability may be exacerbated by changes in the flexibility and / or form of the fabric under wet and / or dry conditions, which Applicants believe may be important to the effectiveness of various embodiments of the disclosed systems and devices. In various embodiments, the enclosure may include one or more walls comprising a flexible material having openings and / or holes formed therethrough. In some desirable embodiments, some or all of the openings through the one or more walls may include a tortuous or "tortuous" flow path, where the tortuosity is defined as the actual length (L) of the flow path. t ) to the straight-line distance between the two ends of the flow path:

[0193]

[0194] In one exemplary embodiment, a woven fabric made from a textured yarn or spun polyester yarn may be highly desirable for use in creating an exemplary shell wall, wherein the spun polyester yarn may have a large number of fiber ends extending from the yarn at various locations and in multiple directions (i.e., a relatively higher level of "hairiness" or fuzz) - desirably creating a more complex 3-dimensional macrostructure and / or multiple tortuous paths from the outer surface to the inner surface of the fabric. In various preferred embodiments, these fiber ends may extend into natural openings that may exist in the fabric weave, thereby potentially reducing and / or eliminating "straight path" openings through the fabric and / or increasing the tortuosity of existing paths through the fabric (which in some cases may extend a considerable distance through the topography of the 3-dimensional fabric). In various embodiments, it may be desirable for portions of the fabric to incorporate openings having a tortuosity greater than 1.25, while in other embodiments, tortuosity greater than 1.5 may be more desirable for various openings in the fabric.

[0195] Permeability

[0196] In many embodiments, it is highly desirable to incorporate permeable elements, components, and / or structures into some and / or all housing components that allow for bulk transport of water into and / or out of the filter media and / or housing in a controlled manner and / or rate. Desirably, the material or materials selected for the filter media / housing will comprise one or more wall structures having a level of permeability that allows for a level of "bulk fluid exchange" between the housing and the surrounding aqueous environment. Desirably, this permeability will be optimized and / or appropriate for the local environment within which the enclosure will be placed, but typically enclosures may incorporate low to moderate levels of permeability, as enclosure materials with very high permeabilities may be somewhat less effective in altering water chemistry within the enclosure and / or limiting or reducing biofouling on the protected article, while enclosure materials with exceptionally low or no permeability (or enclosure materials whose permeability may become very low over time for a variety of reasons, including due to fouling on and / or in the textile surface) may result in unacceptably low levels of liquid exchange through the fabric wall, which may result in various substrate corrosion or other issues caused by low oxygen levels (i.e., anoxic or other conditions) or other chemical levels within the protected environment. Greater or lesser permeabilities or other enclosure design variations may be desirable in various locations and / or environmental conditions, including various changes in seasons and / or weather patterns. In many cases, local environmental conditions (i.e., water flow, temperature, bio-flora type, growing season, salinity, available nutrients and / or oxygen, pollutants, etc.) and / or local water conditions / velocities (i.e., due to currents and / or tides) may affect the desired permeability and / or other design considerations - for example, for a given material permeability, higher velocity liquid impingement on the enclosure may produce increased water exchange rates, which in such cases may require or suggest the use of a lower permeability material.

[0197] In various embodiments, the housing can desirably inhibit biofouling on a substrate or portion of a substrate at least partially immersed in an aquatic environment, wherein the housing comprises a material that is or becomes water permeable during use, the housing being adapted to receive the substrate and form a differentiated aquatic environment extending from a surface of the substrate to at least an inner / outer surface of the structure, wherein the water permeability of the structure or portion thereof is about 100 ml of water per second per square centimeter of substrate or less when or after the structure is positioned about the substrate. In various embodiments, the water permeability of the structure can be achieved by forming the structure to allow water to penetrate through the structure (such as by manufacturing a textile having a desired permeability). In some embodiments, the structure can be designed to become water permeable over time when in use. For example, an otherwise water-permeable structure may include a coating that initially renders it substantially impermeable (such impermeability being particularly useful in “jump starting” desired hypoxic conditions within the enclosure immediately following initial placement), but as the coating ablates, corrodes, or dissolves, the underlying permeability increases and / or becomes useful (which may allow oxygenated water to permeate into / through the enclosure and help prevent unwanted, sustained hypoxic conditions from occurring within the enclosure after hypoxic conditions are achieved).

[0198] In various embodiments, the optimal and / or desired permeability level for the shell fabric can be approximated by any of the fabric permeabilities identified in Table 2 (below), and in some embodiments, can include permeabilities ranging from 100 ml / sec / cm2 to 0.01 ml / sec / cm2. In various alternative embodiments, fabric or other permeable material may be utilized in or on one or more walls of the housing, including materials having a permeability range of: 0.06 ml / sec / cm2 to 46.71 ml / sec / cm2, or 0.07 ml / sec / cm2 to 46.22 ml / sec / cm2, or 0.08 ml / sec / cm2 to 43.08 ml / sec / cm2, or 0.11 ml / sec / cm2 to 42.54 ml / sec / cm2, or 0.13 ml / sec / cm2 to 42.04 ml / sec / cm2, or 0.18 ml / sec / cm2 to 40.55 ml / sec / cm2, or 0.19 ml / sec / cm2 to 29.08 ml / sec / cm2, or 0.32 ml / sec / cm2 to 28.16 ml / sec / cm2 , or 0.48 ml / s / cm2 to 25.41 ml / s / cm2, or 0.50 ml / s / cm2 to 22.30 ml / s / cm2, or 0.77 ml / s / cm2 to 21.97 ml / s / cm2, or 0.79 ml / s / cm2 to 20.46 ml / s / cm2, or 0.83 ml / s / cm2 to 15.79 ml / s / cm2, or 0.90 ml / s / cm2 to 14.72 ml / s / cm2, or 1.05 ml / s / cm2 to 14.19 ml / s / cm2, or 1.08 ml / s / cm2 to 14.04 ml / s / cm2, or 1.11 ml / s / cm2 to 13.91 ml / s / cm2, or 1.65 ml / s / cm2 to 11.27

[0199] ml / s / cm2, or 2.09 ml / s / cm2 to 11.10 ml / s / cm2, or 2.25 ml / s / cm2 to 10.17 ml / s / cm2, or 2.29 ml / s / cm2 to 9.43 ml / s / cm2, or 2.36 ml / s / cm2 to 9.20 ml / s / cm2, or 2.43 ml / s / cm2 to 9.02 ml / s / cm2, or 2.47 ml / s / cm2 to 8.24 ml / s / cm2, or 2.57 ml / s / cm2 to 8.16 ml / s / cm2, or 2.77 ml / s / cm2 to 8.11 ml / s / cm2, or 3.68 ml / s / cm2 to 6.04 ml / s / cm2, or 3.84 ml / s / cm2 to 5.99 ml / s / cm2, or 4.43 ml / s / cm2 to 5.40 ml / s / cm2 and / or 4.70 ml / s / cm2 to 4.77 ml / s / cm2.

[0200]

[0201]

[0202] In various embodiments, the optimal and / or desired water exchange rate between the differentiated environment within the housing and the open environment can range from about 0.1% to about 500% per hour, or 0.1% to about 400% per hour, or about 0.1% to about 350% per hour, or about 20% to about 375% per hour, or about 0.1% to about 100% per hour, or about 0.1% to about 250% per hour, or about 20% to about 500% per hour, or about 50% to about 200% per hour, or about 100% to about 200% per hour, or about 0.1% to about 20% per hour, or about 100% to about 100% per hour. To about 200%, or about 25% to about 200%, or about 25% to about 100%, or about 10% to about 75%, or about 25% to about 275%, or about 100% to about 500%, or about 100% to about 250%, or about 50% to about 150%, or about 75% to about 200%, or about 20% to about 350%, or about 50% to about 100%, or about 0.2% to about 120%, or about 0.2% to about 20% per hour, or about 20% to about 50% per hour, or about 25% by volume per hour.

[0203] The water permeability of a material can be a function of many factors, including the composition of the material, the method and type of construction of the material, whether the material is coated or uncoated, whether the material is dry, wet or saturated, whether the material itself is scaled in some way and / or whether the fabric is "pre-wetted" prior to testing and / or use in an aqueous environment. In addition, because the permeability of a given material can change over time, there may be a range of acceptable and / or optimal water permeabilities even for a single material. In various aspects of the present invention, the water permeability of the enclosure can be an initial minimum permeability that is sufficient to desirably avoid creating constant anoxic conditions in the local (i.e., protected within the enclosure) aquatic environment, while in other embodiments, the permeability can be greater. In various aspects of the invention, the water permeability (ml of water per square centimeter of substrate per second) of the shell material as measured by the above test method achieved before or during use is: about 100 or less, about 90 or less, about 80 or less, about 70 or less, about 60 or less, about 50 or less, about 40 or less, about 30 or less, about 25 or less, about 20 or less, about 10 or less, about 5 or less, about 4 or less, about 3 or less, about 2 or less, about 1 or less, about 0.5 or less, about 0.1 or less, about 1 or greater, about 0.5 or greater, about 0.1 or greater, about 0.1 to about 100, about 0.1 to about 90, about 0.1 to about 80, about 0.1 to about 70, about 0.1 to about 60, about 0.1 to about 50, about 0.1 to about 40, about 0.1 to about 30, about 0.1 to about 25, about 0.1 to about 20, about 0.1 to about 10, about 0.1 to about 5, about 0.5 to about 100, about 0.5 to about 90, about 0.5 to about 80, about 0.5 to about 70, about 0.5 to about 60, about 0.5 to about 50, about 0.5 to about 40, about 0.5 to about 30, about 0.5 to about 25, about 0.5 to about 20, about 0.5 to about 10, about 0.5 to about 5, about 1 to about 100, about 1 to about 90, about 1 to about 80, about 1 to about 70, about 1 to about 60, about 1 to about 50, about 1 to about 40, about 1 to about 30, about 1 to about 25, about 1 to about 20, about 1 to about 10, or about 1 to about 5.

[0204] Optional biocide coating

[0205] In various exemplary embodiments, the disclosed housing may optionally include the use of supplemental biocides and / or antifoulants to the housing to provide sufficient biofouling protection for the housing material and / or substrate, which may also include periodic use of an uncoated fabric housing during certain immersion periods when fouling pressures may prevent the unprotected fabric from macrofouling, and / or when the uncoated housing may be sufficient to provide protection for the contained substrate over a desired period of time. In many embodiments, at least a portion of the surface of the filter medium and / or housing wall structure may be impregnated, injected and / or coated with a biocidal paint, coating and / or additive. In some other embodiments, one or more biocides and / or antifoulants may be integrated into the filter medium and / or housing wall and / or other portions thereof to desirably protect the housing itself from undesirable fouling. In some exemplary embodiments, the fabric or material may serve as a carrier for the biocide.

[0206] Typically, a biocide or some other chemical, compound and / or microorganism that has the ability to destroy, deter, render harmless and / or exert a control effect on any unwanted or undesirable organism by chemical or biological means can be optionally incorporated into and / or onto some or some portion of the material, such as during the manufacture of the material or material components, or the biocide or the like can be introduced into the material after manufacture. Desirably, the one or more biocides in / on the material will inhibit and / or prevent aquatic organisms from colonizing the exterior surface and / or within the openings in the enclosure, as well as repel, incapacitate, harm and / or weaken biofouling organisms to be small enough to attempt or successfully penetrate the openings in the enclosure, such that the fouling organisms are less able to thrive in the artificial or synthetic localized aquatic environment between the structure and the substrate. In various embodiments, the housing desirably incorporates a material that maintains sufficient strength and / or integrity to allow protection and / or inhibition of biofouling (and / or enable creation of a desired artificial local aquatic environment or synthetic local aqueous environment) over a useful life of not less than about 3 to 7 days, 7 to 15 days, 3 to 15 days, at least 1 month, at least 3 months, at least 6 months, at least 12 months, at least 2 years, at least 3 years, at least 4 years, and / or at least 5 years or more.

[0207] In at least one exemplary embodiment of the hull, the hull may incorporate a material coated, painted and / or impregnated with a biocide coating that desirably adheres to and / or penetrates the material at a desired depth (which may include surface coatings of the material on only one side of the fabric, as well as coatings that may penetrate 1% to 99% of the fabric, as well as coatings that may completely penetrate the fabric and coat some or portions of all opposing sides of the fabric). Desirably, the biocide will reduce and / or prevent the type, rate and / or extent of biofouling on the material, and / or may have some deleterious effect on microorganisms attempting to enter the differentiated aqueous environment through openings in the material (and may also have some effect on microorganisms already present in the hull). In various embodiments, the presence of a biocide coating or paint along a 3-dimensional "entry path" into the hull (i.e., as microorganisms pass through openings and / or holes in the material) will desirably provide a greater surface area and prove more effective than the standard two-dimensional "flat" paint biocide coverage utilized on rigid submerged surfaces used offshore today (i.e., hard flat coatings). In various aspects, particularly where the fabric substrate material is highly fibrillated and / or ciliated, coatings of such materials can be expected to provide a higher fabric "functional surface area" for the biocide coating to adhere to, which desirably increases the potential anti-biofouling efficacy because as organisms pass through the fabric, they are more likely to localize in proximity to and / or contact with these small fibers (and the biocide paint, coating or additive residing thereon or therein).

[0208] In various alternative embodiments, the housing may incorporate a material coated, painted and / or impregnated with a biocide coating (which may include a surface coating of the material on only one side of the fabric, and a surface coating that may extend from the front and / or back of the fabric a certain amount into the pores of the fabric), which may include a coating on one surface of the fabric that penetrates up to 5% of the pores of the fabric, up to 10% of the pores of the fabric, up to 15% of the pores of the fabric, up to 20% of the pores of the fabric, up to 25% of the pores of the fabric, up to 30 ... Up to 35%, up to 40% into the pores of the fabric, up to 45% into the pores of the fabric, up to 50% into the pores of the fabric, up to 55% into the pores of the fabric, up to 60% into the pores of the fabric, up to 65% into the pores of the fabric, up to 70% into the pores of the fabric, up to 75 into the pores of the fabric, up to 80% into the pores of the fabric, up to 85 into the pores of the fabric, up to 90% into the pores of the fabric, up to 95 into the pores of the fabric, up to 99 into the pores of the fabric, up to 100% through the pores of the fabric and / or extending from the pores to the opposite surface of the fabric.

[0209] In various embodiments, incorporating additional biocide coatings or other coatings / additives also desirably improves the durability and functional life of the filter media, housings, and / or components thereof in some embodiments, since biofouling organisms and / or other harmful agents should be inhibited and / or prevented from colonizing in the flexible fabric and / or perforations for a period of time after immersion, thereby desirably maintaining the flexibility, perforated nature of the housing wall and the attendant advantages. In the case where the biocide is primarily retained near the fabric substrate (i.e., in the case where there may be very low or no biocide elution levels on the outside of the fabric or housing), the biocide will desirably significantly inhibit biofouling of the housing wall, while the presence of the housing and the "differentiated aqueous environment" created therein will reduce and / or inhibit biofouling of the protected substrate. In various exemplary embodiments, the biocide has extremely low detectable levels and / or no detectable levels in water within the differentiated aqueous environment and / or in open water adjacent to the housing (i.e., less than 30 ng / L), and still remains highly effective in protecting the housing and / or substrate from biofouling. In one example, the release rate of the biocide from the shell material was detected to be 0.2-2 ppm and / or lower within 7 days in artificial seawater, and at local low concentrations (i.e., the release rate of the biocide) was detected to be 0.2-2 ppm and / or lower within 7 days in artificial seawater, and these release rates effectively protected the shell material from biofouling.

[0210] Various supplemental coatings incorporating various biocides and / or other dispensing and / or eluting materials may be incorporated into a given housing design to provide various antifouling advantages. For example, coatings that release econea and / or pyrithione in varying amounts and / or times may be used to combat biofouling, including embodiments that initially have a high release rate that decreases significantly after only a few days and / or weeks after immersion, and other embodiments that initially have a low release rate that increases with immersion time.

[0211] In at least one exemplary embodiment, the shell material may include a spun polyester fabric having a surface and / or subsurface coating of a commercially available biocide coating, including water-based and / or solvent-based coatings containing registered biocides, as well as coatings applied to the fabric by virtually any means known in the art, including by brushing, roller coating, painting, dipping, spraying, production printing, encapsulation, and / or screen coating (with and / or without vacuum assistance). Coating of the material may be accomplished on one or both sides of the material, as well as single-sided coating on the inward-facing side of the material, although single-sided coating on the outward-facing side of the material (i.e., away from the substrate and toward the open aqueous environment) has demonstrated significant levels of effectiveness while minimizing biocide content, cost, and maintaining favorable flexibility. Although water-based ("WB") biocide coatings are primarily discussed in the various embodiments herein, solvent-based ("SB") biocide coatings may alternatively be used in a variety of applications (and / or in combination with water-based coatings) if desired.

[0212] In various embodiments, the use of various printing processes for the coating can have the added benefit of allowing visible patterns and / or logos to be incorporated into and / or onto the shell wall, which can include marketing and / or advertising materials for identifying the source of the shell (i.e., the shell manufacturer) and identifying one or more users (i.e., a specific marina and / or ship owner / ship name) and / or identifying the intended area of ​​use and / or conditions (i.e., "submerged in salt water only" or "for use only in Jacksonville Harbor" or "for use only in summer"). If desired, various indicators can be incorporated to identify the age and / or condition of the shell, including printing a "replacement date" on the exterior of the shell. If desired, the biocide coating itself can be used to print visible patterns, the biocide coating can incorporate supplemental inks and / or dyes into the coating mixture, or a separate additive can be used to print additional logos, etc.

[0213] In various embodiments, the biocide coating or paint may be desirably applied to the material in an amount ranging from 220 grams to 235 grams per square meter, although less than 220 grams per square meter (including 100 grams per square meter or less) and more than 235 grams per square meter (including 300 grams per square meter and more) are shown to have significant potential. In various alternative embodiments, the coating mixture may include one or more biocides by various percentage weights of the mixture, including 10% or less of the weight of the biocide, such as 2%, 5% and / or 7% of the mixture, or greater amounts of biocide, including 10%, 20%, 30%, 40%, 50% and / or more biocides by weight of the coating mixture, and actually covers the range of its combination (i.e., 2% to 10% and / or 5% to 50%, etc.). In the case where the housing design may be particularly large, it may be desirable to significantly increase the percentage of biocide in the coating mixture, which will desirably reduce the total amount of coating required to protect the housing and / or substrate.

[0214] Fig.16 A cross-sectional view of an exemplary permeable fabric 2100 is depicted having individual pore openings 2110 and simplified channels 2120 extending from a front face 2130 to a back face 2140 of the fabric 2100. Also shown is a coating substance 2150 optionally containing a biocide or other debilitating substance, wherein portions of this coating substance extend at least a distance "D" from the front face 2130 into the pore openings 2110 and / or channels 2120 of the fabric 2100. In various embodiments, it is desirable that the coating substance will penetrate a certain average distance "D" into the openings / pores of the fabric and / or fabric wall of the material (i.e., a penetration depth into the fabric of 3%, 5%, 10%, 15%, 20%, 25%, 50%, 75%, or more - see Fig.16 ). Desirably, the coating material (which is often "harder" than the fabric to which it is applied in a dry configuration) is applied in a manner that allows the fabric to be bent and / or molded to some extent (i.e., the coating will desirably "stiffen" the fabric to an undesirable degree), thereby allowing the fabric to be formed into a desired shell shape and / or wrapped around a structure and / or formed into a flexible bag and / or container (if desired). In the case of providing a bag or similar shell (i.e., a closable shape), it may be desirable to apply the coating to / in the article after the article is manufactured, which may include coating and / or encapsulation of any seams and / or stitched / adhesion areas beneath one or more coatings. In various embodiments, the coating penetration depth will, on average, not exceed half of the depth through the material.

[0215] Once coated with a coating or paint, the material and / or housing can be allowed to cure and / or air dry for a desired period of time (which may take less than two minutes for some commercial applications, or up to an hour or more in other embodiments) or can be force dried using gas, oil, or electric heating elements. The material and / or housing can then be used as described herein.

[0216] In various embodiments, the shell may include an optional biocide that is attached to, coated on, encapsulated, integrated into, and / or "woven into" the strands of the material. For example, the biocide may be incorporated into strips containing various concentrations of one or more biocides, thereby desirably preventing various animal and plant species from attaching to or existing on and / or in the shell. Alternatively, the shell may include a reservoir or other component containing the biocide in free or microencapsulated form. Microencapsulation desirably provides a mechanism in which the biocide can be diffused or released into the environment in a time-dependent manner. Microcapsules filled with biocides may be embedded in individual strands and / or woven materials without the use of a reservoir or container, or alternatively the biocide may be coated on the surface of the fiber substrate element (i.e., strands) and / or the openings or "holes" therebetween.

[0217] Other methods of inserting and / or applying the coating or antifouling agent are contemplated, such as application using a spray known to those skilled in the art of coatings. In addition, the housing need not contain separate fiber elements, but can be made of a perforated and / or flexible sheet material containing the agent embedded therein and / or coated on the material. To provide a securing mechanism, the housing can include fastening elements, such as, but not limited to, loop and hook type fasteners, such as Snaps, buttons, hooks, clips, buttons, adhesive strips or zippers. If desired, the shell may desirably include multiple wall structures, each of which is attached to one or more adjacent wall structures (if any) by stitching, weaving, etc., which may include coatings and / or encapsulations of any seams and / or stitching / adhesion areas below one or more coatings for forming a modular shell. If desired, shell material may be added to extend beyond and / or onto the shell fastening elements to protect the fastening elements from fouling.

[0218] In various embodiments, the shell desirably comprises anti-biofouling properties attached and / or embedded within the threads and / or fibers (i.e., various elements of the fiber matrix) to inhibit and / or prevent biofouling of the shell. In preferred embodiments, the anti-biofouling agent is a biocide coating comprising Econea TM(tralopyril - commercially available from Janssen Pharmaceutical NV, Belgium) and / or omadine zinc (i.e., pyrithione), but other anti-biofouling agents known to those skilled in the art, such as zinc, copper, or derivatives thereof, currently available and / or developed in the future, may be used. In addition, antifouling compounds from microorganisms and their synthetic analogs may be utilized, wherein these various sources are generally classified into ten types, including fatty acids, lactones, terpenes, steroids, benzyl compounds, benzyl ethers, polyketides, alkaloids, nucleosides, and peptides. These compounds may be isolated from seaweed, algae, fungi, bacteria, and marine invertebrates (including larvae, sponges, worms, snails, mussels, etc.). One or more of any of the previously described compounds and / or their equivalents (and / or any future developed compounds and / or their equivalents) (or various combinations thereof) can be used to create anti-biofouling structures that prevent both microfouling (such as biofilm formation and bacterial attachment) and macrofouling (attachment of large organisms (including barnacles or mussels)) against one or more target species, or, if desired, can be used as a "broad-spectrum" antifouling agent against a variety of biofouling organisms.

[0219] In an exemplary embodiment, a desired woven fabric based on spun polyester fibers may be used as an outer shell wall material, wherein the fabric has a basis weight (including the weight of the base fabric prior to any coating or modification) of approximately 410 grams per square meter (see Table 3).

[0220]

[0221] Table 3: Exemplary fabric specifications

[0222] Table 4 depicts some alternative fabric specifications that may be used as shell materials with varying levels of utility.

[0223]

[0224] Table 4: Additional Exemplary Fabric Specifications

[0225] For various structures or housing embodiments, the target add-on weight on the paint / coating can be set at approximately 5 g / m2 to 500 g / m2, approximately 50 g / m2 to 480 g / m2, approximately 100 g / m2 to 300 g / m2, approximately 120 g / m2 to 280 g / m2, approximately 224 g / m2 (or up to ±10% thereof).

[0226] In various embodiments where it may be desirable to add a biocide or other coating, it should be understood that in some embodiments, the coating may be applied to the housing after the housing is fully assembled and / or constructed, while in other embodiments, the coating may be applied to some or all of the components of the housing before assembly and / or construction. In still other embodiments, some portions of the housing may be pre-coated and / or pre-treated, while other portions may be coated after assembly. In addition, where processing and / or handling steps during manufacture and / or assembly may involve techniques that may negatively impact the quality and / or performance of the biocide or other coating characteristics, it may be desirable to perform those processing and / or handling steps on the housing and / or housing components prior to applying their coatings. For example, where heat-sensitive biocides and / or coatings may be desired, material processing techniques involving high temperatures may be employed to produce and / or process the fabric and / or housing walls prior to applying their biocide coatings (i.e., to reduce the chance of heat-related degradation of the biocide and / or coating).

[0227] In various embodiments, coating materials or other additives (including biocide coatings or other materials) can be applied to and / or incorporated into the fabric of the shell, potentially resulting in a change in permeability level, which can convert a material that may be less suitable for protecting a substrate from biofouling into a material that is more desirable to protect a substrate from biofouling in the coated state. For example, uncoated polyester fabric, which has been experimentally demonstrated to have a high permeability to liquids (i.e., 150 mL of liquid passed through the test fabric in less than 50 seconds), is less desirable for forming an enclosure for protecting a substrate from biofouling, as described herein. However, when properly coated with a biocide coating to a desired level, the permeability of the coated fabric can be greatly reduced to a more desirable level, such as a moderately permeable level (i.e., 100 mL of liquid passed through the test fabric in between 50 and 80 seconds) and / or a very low permeability level (i.e., almost no liquid passed through the test fabric). In this way, if desired, a deliberate permeability level can be optionally "dialed into" or adjusted for each selected fabric.

[0228] During immersion testing in an aqueous environment over an extended period of time, one embodiment of the housing incorporating a polyester coated fabric did not form macrofouling and / or a very small macrofouling coating. Additionally, one example of the polyester fabric became more permeable during immersion, while the other example became less permeable during immersion.

[0229] Fig.17ADepicted is an exemplary embodiment of an uncoated 23×23 polyester woven fabric that has been experimentally demonstrated to have a low permeability to liquids (i.e., 100 mL of liquid passed through the test fabric in approximately 396 seconds), which may be at the low end of the desired permeability range for forming some enclosure designs to protect substrates from biofouling, depending on local conditions as described herein. When coated (see Fig. 17B ), these materials become substantially impermeable prior to immersion, but become more permeable after immersion. As previously described, the desired permeability level can be "dialed in" or adjusted for each desired fabric, if desired. In various embodiments, the permeability of a given fabric and / or shell component can be altered or different in wet or dry conditions, if desired.

[0230] During immersion testing in an aqueous environment over an extended period of time, both the uncoated 23×23 polyester and the coated polyester fabrics showed no macroscopic fouling on the shell and / or substrate. In addition, each of these materials showed significantly improved permeability during immersion, with the 23×23 uncoated polyester fabric allowing 150 mL of liquid to pass through in 120 seconds, while the first 23×23 coated polyester fabric allowed 150 mL of liquid to pass through in 160 seconds, and the second 23×23 coated polyester allowed 150 mL of liquid to pass through in 180 seconds.

[0231] In other alternative embodiments, Figures 18A to 18C Depicts the uncoated ( Fig.18A ), coated with a solvent-based bactericidal coating ( Fig.18B ) and coated with a water-based bactericidal coating ( Fig. 18C ) of natural materials, burlap. During the permeability test, the permeability of the uncoated burlap fabric was demonstrated to be 50.99 ml / sec / cm2, while the permeability of the coated burlap fabric was 52.32 ml / sec / cm2 and 38.23 ml / sec / cm2 for the solvent-based biocide coating and water-based biocide coating, respectively. After 32 days of immersion in salt water, the permeability of both coated fabrics increased significantly to 85.23 ml / sec / cm2 and 87.28 ml / sec / cm2, while the permeability of the uncoated burlap fabric decreased to 20.42 ml / sec / cm2. For fouling observations, the uncoated burlap fabric experienced very little fouling, and the coated burlap fabric experienced almost no macro fouling.

[0232] Additionally, in another alternative embodiment, the uncoated fabric of 1 / 64 polyester is coated with a solvent-based bactericidal coating, and alternatively coated with a water-based bactericidal coating. During the permeability test, the permeability of the uncoated 1 / 64 polyester fabric was proved to be 26.82 ml / sec / cm2, while for the solvent-based bactericidal coating and the water-based bactericidal coating, the permeability of the coated 1 / 64 polyester fabric was 44.49 ml / sec / cm2 and 29.25 ml / sec / cm2, respectively. After being immersed in salt water for 32 days, the permeability of all 1 / 64 polyester fabrics significantly decreased to 10.99 ml / sec / cm2, 13.78 ml / sec / cm2 and 13.31 ml / sec / cm2, respectively. For fouling observation, the uncoated 1 / 16 polyester fabric experienced some fouling, but the coated 1 / 64 polyester fabric almost did not experience macroscopic fouling.

[0233] In constructing and testing anti-biofouling enclosures, a variety of different fabrics have been manufactured, coated, and utilized. Fig.19A ), a deformed polyester cloth is coated with a biocide coating on a first surface, wherein a significant amount of this coating penetrates completely through the cloth to an opposing second surface (wherein some areas of the coating on the second surface are thinner than other areas). Fig.19B The coated cloth is depicted at a scale of 1000 μm. On average, the coated cloth had 523.54 (± 2.33) pores per square inch, with approximately less than 5% of the pores being blocked (on average).

[0234] Fig.19C Another preferred embodiment of a 100% spun polyester fabric is depicted, wherein Fig.19D This fabric coated with a bactericidal coating is depicted. During testing, the permeability of the uncoated 100% polyester fabric was demonstrated to be 10.17 ml / sec / cm2 of the fabric, while the permeability of the coated polyester fabric was 0.32 ml / sec / cm2 and 1.08 ml / sec / cm2. After 23 days of immersion, there was no significant change in the permeability of both coated fabrics, with the uncoated poly fabric experiencing very little fouling and the coated polyester fabric experiencing almost no macro fouling. However, in various other embodiments, it is expected that the method for preparing spun polyester yarn (such as core-spun staple fibers around a continuous core, open-end spinning, ring spinning, and / or air-jet spinning) will also produce favorable results.

[0235] In another embodiment ( Fig.19EThe uncoated fabric shown in FIG. , where the scale bar is 500 μm), the spun polyester cloth is subsequently coated with a biocide coating on a first surface, wherein a significant amount of this coating partially penetrates the fibers and / or pores of the cloth (in some embodiments, the penetration rate through the cloth is as much as or more than 50%). Fig.19F The opposite uncoated side of the fabric at 1000 μm is shown, where this figure also demonstrates that significant pore size reduction can be achieved using this coating technology if desired. On average, this coated cloth has 493 (± 3.53) pores per square inch, with approximately 7% to 10% of the pores being completely blocked by the coating material (on average).

[0236] Experimentally, all of these fabric embodiments demonstrated desirable levels of permeability, which may be due to the large number of small pores, smaller fiber size, and / or various combinations thereof. The various coating methods were very effective in coating and permeating the fabrics to the desired levels and produced highly effective materials for incorporation into protective enclosures.

[0237] Table 2 depicts various fabrics potentially suitable for use in various embodiments of the present invention, and exemplary permeabilities of these fabrics in an uncoated state and a coated state. For example, in the Port Canaveral Harbor (Port Canaveral, Florida, USA), experimentally determined permeabilities ranged from 0.5 ml / sec / cm2 to 25 ml / sec / cm2 to 50 ml / sec / cm2 to 75 ml / sec / cm2 to 100 ml / sec / cm2, or about 0.1 ml / sec / cm2 to about 100 ml / sec / cm2, or about 1 ml / sec / cm2 to about 75 ml / sec / cm2, or about 1 ml / sec / cm2 to about 10 ml / sec / cm2, or about 1 ml / sec / cm2 to about 5 ml / sec / cm2, or about 5 ml / sec / cm2 to about 10 ml / sec / cm2, or about 10 ml / sec / cm2 to about 20 ml / sec / cm2, or about 10 ml / sec / cm2 to about 25 ml / sec / cm2 A permeability range of ml / sec / cm2, or about 10 ml / sec / cm2 to about 50 ml / sec / cm2, or about 20 ml / sec / cm2 to about 70 ml / sec / cm2, or about 10 ml / sec / cm2 to about 40 ml / sec / cm2, or about 20 ml / sec / cm2 to about 60 ml / sec / cm2, or about 75 ml / sec / cm2 to about 100 ml / sec / cm2, or about 60 ml / sec / cm2 to about 100 ml / sec / cm2, or about 10 ml / sec / cm2 to about 30 ml / sec / cm2 may be sufficient (depending on local conditions) to prevent a significant amount of scaling from occurring on and / or within the enclosure and / or on the protected substrate, while still allowing sufficient water flow to inhibit and / or prevent oxygen deficiency within the enclosure. In addition, fabrics having a permeability of 0.5 ml / sec / cm2 or less may be suitable for various shell embodiments in which occasional periods of hypoxic conditions are acceptable and / or desired. Permeabilities below these ranges may result in anoxic conditions during periods of low water movement in some areas, which may be less desirable and / or undesirable in various embodiments. In another exemplary embodiment, a permeability range of at least 0.32 ml / sec / cm2 and up to 10.17 ml / sec / cm2 is determined as an optimal range of permeability characteristics and / or an expected range of permeability changes expected during the useful life of the shell. In other embodiments, a range of at least 1.5 ml / sec / cm2 and up to 8.0 ml / sec / cm2 (and any combination of the various ranges disclosed herein) may be desired.In many cases, because the specific fouling organisms, the incidence of fouling intrusion and / or fouling growth rate in a given area and / or body of water may be highly dependent on a variety of relevant factors, as well as local and / or seasonal conditions in the intended area of ​​use (and the intended substrate to be protected, etc.), the acceptable range of permeability for a given fabric in a given enclosure design may vary greatly - thus, the permeability of a fabric may be optimal and / or suitable for one enclosure design and / or location and may be less optimal and / or unsuitable for use in another enclosure design and / or location. Therefore, the expected permeability values ​​and ranges thereof should be interpreted as general trends in the ability of a given fabric and / or permeability to provide antifouling protection in avoiding prolonged anoxic conditions in a given body of water, but should not be interpreted as excluding the use of a given fabric in other enclosure designs and / or water conditions.

[0238] In various embodiments, the permeability of the filter media and / or housing material can be desirably maintained in situ within a desired permeability range throughout its useful life (or, if desired, until a desired biofilm layer has been established), such that potential increases in material permeability due to changes in the structure and / or material of the housing (as an example) will desirably approximate various expected decreases in material permeability due to pore plugging by organic and / or inorganic debris (including any biofouling of the material and / or its pores that may occur). This balance will desirably maintain the integrity and / or functionality of the housing and the characteristics of the differentiated environment over an extended period of time, thereby providing significant protection for the housing and / or protected substrate.

[0239] In various embodiments, the shell wall can be combined with a variety of materials that experience permeability changes during immersion testing in an aqueous environment over an extended period of time. For example, uncoated synthetic materials will generally become less permeable over time (this may be due to the gradual fouling of the fabric once positioned around the substrate), while some materials coated with a bactericidal coating may experience various permeability changes, including some embodiments becoming less permeable over time. In addition, the permeability of uncoated natural test fibers (burlap) becomes higher, while the permeability of biocide-coated burlap becomes lower over time. In various embodiments, changing coating parameters (i.e., coating addition / thickness, application method, vacuum application for maintaining and / or increasing pore size, drying parameters, etc.) and changing textile parameters (i.e., structure, material, initial permeability, whether or not constrained during drying, whether heat setting, etc.) can produce a wide range of desired permeability characteristics and expected permeability changes within a given shell design life. When deployed in an aqueous environment, it is therefore possible to influence (and / or control) whether the permeability increases or decreases over time over one or more extended time periods, and the relevance to the product life cycle.

[0240] In various embodiments, the housing can desirably inhibit biofouling on a substrate that is at least partially immersed in an aquatic environment, wherein the housing comprises a material that is or becomes water permeable during use, the housing being adapted to receive the substrate and form a differentiated aquatic environment extending from a surface of the substrate to at least an inner / outer surface of the structure, wherein when the structure is positioned on or around the substrate, the water permeability of the structure or a portion thereof is about 100 milliliters of water per second per square centimeter of substrate or less, about 100 milliliters of water per minute per square centimeter of substrate, or values ​​therebetween or greater / lesser permeabilities.

[0241] In various embodiments, water permeability of a structure can be achieved by forming the structure to allow water to penetrate through the structure, for example by weaving a textile to have a desired permeability and / or optionally coating the textile with a biocide coating that provides the textile with the desired permeability (or a coating that does not contain a biocide). In some embodiments, a structure can be designed to become water permeable over time when in use. For example, an otherwise water permeable structure can have a coating that initially makes it substantially impermeable, but as the coating ablates, erodes, or dissolves, the underlying permeability increases and / or becomes useful.

[0242] Table 5 (below) depicts an exemplary test of water permeability of an enclosure incorporating a permeable fabric wall. In this example, an initial high concentration of rhodamine was generated in the enclosure in an aqueous environment, and then the rhodamine concentration was measured over time to determine how the concentration of this marker decreased as water exchanged in and out of the permeable wall of the enclosure. The test showed that the residence time of rhodamine in this enclosure, along with its size and wall permeability, was approximately 4 hours and 10 minutes, with a half-life of 3 hours and a flow rate of approximately 0.0027 ml / cm2 / sec.

[0243]

[0244] Table 5 - Rhodamine dye test

[0245] The rhodamine dye test is used as a simulant for determining the water exchange rate in various test housings. For example, a YSI total algae sensor (TAL) is placed in a bagged boat stern simulant. Rhodamine at a concentration of 0.9 mg / L is added to the boat stern simulant. When the data returns to the background concentration of the pigment in the bag, the YSI is placed in open water for 2 days to obtain open water readings to compare with the undosed bag level. Residence time, half-life and flow rate are calculated from the rhodamine data. The residence time is calculated as 37% of the initial concentration of the rhodamine dye. The half-life is calculated as 69.3% of the residence time (using these calculations found in the literature). The flow rate is calculated by multiplying the volume by 2 times (by 1 volume in and 1 volume out), and then dividing it by the residence time and surface area. After subtracting the background pigment, the rhodamine concentration expressed in mg / L is plotted to better understand the dilution rate. The test results show that the pigment concentration in the boat stern simulant takes about 26 hours to stabilize back to the natural level. The residence time was calculated to be 4 hours and 10 minutes, with a flow rate calculated to be 0.0027 ml / cm2 / sec.

[0246] In various embodiments, it is highly desirable that the shell or its part has an initial high permeability, wherein a reduction in permeability occurs subsequently after the shell is placed around the substrate to be protected. For example, a shell with extremely low permeability may maintain positive buoyancy after being placed in an aqueous medium, which may make it difficult to place the shell around a submerged and / or partially submerged substrate even if it is not impossible. In contrast, a shell incorporating more permeable elements may be more likely to "sink" when deployed around the substrate. Such shells may include a highly permeable lower portion (to allow water to flow into and quickly fill the shell), wherein the permeability of other shell elements is higher or lower. Once deployed around the substrate as required, the element with higher permeability can change the permeability (that is, the permeability is higher or lower), or the same permeability can be maintained as required.

[0247] In various embodiments, with the use of an enclosure as described herein, the biological colonization sequence on the substrate can be interrupted (destroyed, altered, etc.) to reduce and / or minimize the sedimentation, recruitment, and eventual macrofouling of the substrate. Once positioned around or within the substrate (if protecting the inner surface of the substrate), the permeable protective fabric wall of the enclosure can desirably filter and / or prevent various microorganisms and / or macroorganisms from entering the enclosure, and in some embodiments, the optional biocide coating can prevent fouling of the enclosure and / or may injure and / or damage some and / or all of the organisms as the organisms contact and / or pass through the fabric. If desired, the bactericidal coating may undergo significant bactericidal washout when initially placed around the substrate to establish an initial higher "kill level" that affects fouling organisms, wherein as the water chemistry in the enclosure changes, the bactericidal washout level will significantly decrease over a period of time to create a desired differentiated environment, thereby protecting the substrate from further fouling.

[0248] In one exemplary embodiment, testing of microscopic plankton passing through a biocide-coated permeable fabric membrane of an enclosure indicated that some organisms were likely to remain alive and viable after passage, while some other organisms were likely to be damaged and / or injured during passage. Observations of live organisms within the enclosure were enhanced by testing the differentiated water within the enclosure, where a significant portion of microorganisms within the enclosure that use attachments (e.g., barnacle larvae and tunicates, with velocities in the range of 1-10+ cm / sec) and many viable microorganisms that use cilia (e.g., bivalve veligers and tube worms, with velocities in the range of 0.5-2 mm / sec) appeared to remain viable within the biocide-coated enclosure. However, even if live fouling organisms were present within the enclosure and / or in direct contact with the substrate, the protective features of the enclosure prevented these live and / or viable organisms from thriving and / or colonizing the protected substrate.

[0249] Fig.21 Describe various plankton types and conditions (i.e., alive or dead) identified in various shells by permeable fabric types. In various shell tests, the results show that in the fabric shells coated with biocides, the condition of swimmers is worse than that of good swimmers, which indicates that the biocide may have injured or otherwise affected the larvae, which were swept into the shells with the coated fabrics and then could not escape. In addition, "good" swimmers may have been able to swim out of the shells, and "poor" swimmers may not be able to leave the shells due to limited water movement in the shells. This observation has further been supported by the fact that compared with uncoated fabrics and open samples, the swimmers in the coated fabric shells are significantly worse. It seems that the total number of plankton in the coated fabric shells is more than the total number of plankton in the uncoated fabric shells.

[0250] Although some embodiments of the present invention have been described in the form of a skirt shell, the shape of the anti-biofouling shell can be suitable for any structure. In various embodiments, the shell material can be provided in the form of a rolled sheet, with or without a biocide or other coating applied to the outer surface of the sheet material, which can include significant penetration into the sheet material and / or through the sheet material, or can alternatively include a biocide or other anti-biofouling material incorporated into the sheet material, which can be customized using microencapsulation to release the biocide. In this way, the anti-biofouling shell can be placed on various types of aquatic structures, such as nets, water intake pipes, sewage pipes and / or water storage tanks, water system control valves and safety valves, offshore systems, irrigation systems, power plants, pipeline valves and safety control systems, military and commercial monitoring sensors and arrays, etc. Other embodiments may include support columns for aquatic structures, bridges, floodwalls, dikes and / or dams. In order to extend the service life of underground structures extending above water, the support structure and the base structure can be combined with packaging materials (tightly or loosely combined) and / or similar shells.

[0251] Other objects that may be protected include tethered and / or free-floating structures such as buoys and / or sensors. Housings may be attached to portions of the buoy that are near or in direct contact with the aquatic environment to prevent the accumulation of biofouling in these areas, as well as wrapped or closed / bounded envelope structures, blankets, and / or sleeves placed around the connections and / or cables that anchor the buoy to the seafloor.

[0252] Once the enclosure is appropriately positioned around the substrate to the desired extent (including embodiments that may not completely enclose the substrate, and / or embodiments that may only partially enclose the substrate), in some embodiments, the effect on the enclosure will desirably create a unique aqueous environment in the area immediately surrounding the substrate and / or other objects, wherein the purpose is to (1) buffer and / or minimize exposure of the substrate from intrusion of otherwise viable microscopic and / or macroscopic fouling agents, (2) filter any liquid entering and / or flowing out of the enclosure, (3) reduce and / or eliminate the effect of sunlight or other light / energy sources on the differential aqueous environment. (4) regulating the amount of dissolved oxygen and / or other water chemistry values ​​in the differentiated environment, (5) metering, controlling and / or limiting liquid exchange between the differentiated environment and the open environment, including reducing the velocity and / or turbulence of the liquid within the enclosure, (6) insulating and / or isolating the substrate from the charge and / or charged fouling particles, and (7) if desired, maintaining various water chemistry values ​​within the differentiated environment, such as pH, temperature, salinity and / or other environmental factors, that are closely approximate to those of the surrounding open environment. In addition, in various embodiments, it is desirable to protect some or all of the enclosure itself from significant biofouling through the activity of the biocide coating, the elution of various chemicals from the interior of the enclosure, the flexibility of the enclosure material and / or the potential for shedding or other detachment of biofouling agents from one or more enclosure structures.

[0253] Biofouling protection using changes in water chemistry

[0254] In many of the embodiments described herein, once the housing or filter medium is "separated", "enclosed" or otherwise partially and / or completely adjacent to a substrate or other system to form a "separated" water area, the disclosed biofouling protective system can provide a significant level of protection for the substrate, many of which still allow a certain amount of liquid exchange between the open environment and the separated or closed environment, such as penetration through the housing wall into the differentiated environment, and similarly, a certain amount of liquid from the differentiated environment can still penetrate through the housing wall into the open environment. Desirably, the design and positioning of the protective housing around the substrate can optionally change the various water chemical characteristics and / or components of the closed environment to a meaningful extent compared to those of the open aqueous environment. In various cases, the housing can cause some water chemical characteristics to be "different" compared to the surrounding aqueous environment, while other water chemical characteristics can remain the same as the water chemical characteristics in the surrounding aqueous environment. For example, in the case where the dissolved oxygen level is often "different" between the differentiated environment and the open environment, the temperature, salinity and / or pH levels within the differentiated environment and the open environment can be similar or the same. Desirably, the enclosure can affect some water chemistry characteristics in a desired manner, while leaving other water chemistry characteristics minimally affected and / or "unchanged" compared to those of the surrounding open aqueous environment. Some exemplary water chemistry characteristics that may potentially "be different" and / or may remain unchanged (i.e., depending on enclosure design and / or other environmental factors such as location and / or season) may include dissolved oxygen, pH, total dissolved nitrogen, ammonium, nitrate, nitrite, orthophosphate, total dissolved phosphate, silica, salinity, temperature, turbidity, chlorophyll, etc.

[0255] In some exemplary embodiments, a measure of one or more water chemical characteristics inside the housing may be "different" compared to an equivalent measurement outside the housing (which may include a measurement at a distance removed from the housing to account for potential elution outside the housing (e.g., only 1 or 2 inches or more, or even 1, 2, 3, 5, 10, 20 feet or more from the housing outer wall)). Such a "difference" may include a 0.1% or greater difference between the inside / outside measurements, or a 2% or greater difference between the inside / outside measurements, or a 5% or greater difference between the inside / outside measurements, or a 8% or greater difference between the inside / outside measurements, or a 10% or greater difference between the inside / outside measurements, or a 15% or greater difference, or a 25% or greater difference, or a 50% or greater difference, or a 100% or greater difference. Additionally, such a difference may be for multiple chemistries with unequal differences or may include an increase in one factor and a decrease in another factor. Combinations of all such described water chemistry factors are contemplated, including situations in which some of the water chemistry factors remain substantially the same for some factors while other factors may vary.

[0256] In various embodiments of the present invention, the housing can create a "differentiated aqueous environment" near the substrate, but the housing can also allow for controlled or metered "mixing" and / or other transport between liquids and / or other substances within the housing and liquids and / or other substances in the surrounding aqueous environment (i.e., outside the housing). Such controlled transport that can occur both into and / or out of the housing desirably creates unique aqueous environments within various portions of the housing that inhibit and / or prevent the formation of significant amounts of biofouling on the substrate. For example, dissolved oxygen in seawater originates from one of three sources: (1) atmospheric oxygen that dissolves, diffuses, and / or mixes (i.e., through aeration) into the water surface, (2) oxygen released by algae, underwater grasses, and / or other biological processes as a result of photosynthesis or other metabolic pathways, and / or (3) oxygen present in streams and river flows that mixes into the seawater. When properly designed and deployed in an appropriate environment, the housing structure can also desirably block and / or inhibit significant amounts of sunlight from penetrating into the differentiated aqueous environment, thereby reducing the amount of dissolved oxygen produced by photosynthesis within the housing. In addition, due to various factors (including because the housing can bend to varying degrees), the presence of the housing wall will desirably reduce and / or inhibit a significant amount of the physical flow of water into, through and / or out of the housing due to horizontal and / or vertical water flow (or a combination thereof), which allows the housing wall to provide at least a partial barrier to the water flow while also allowing the housing wall to change shape and / or orientation to a meaningful degree to reduce flow resistance, and also because the flexible housing wall can "move" and / or deform to varying degrees with the water flow, thereby reducing the pressure differential that encourages water to flow through the pores of the wall fabric.

[0257] In at least one exemplary embodiment, when the shell of the present invention is first placed around the substrate, the dissolved oxygen in the differentiated aqueous environment can be rapidly depleted from the inside of the shell by the organisms, metabolism and / or other processes and / or activities in the shell to produce an oxygen depletion zone in the shell. However, since the shell allows some water to flow into and / or out of the shell in large quantities (i.e., water exchange between the shell and the surrounding "open" water), a certain amount of oxygen replenishment will occur as oxygen-containing water flows through the shell wall, and a certain amount of oxygen-depleted water will flow out of the shell wall. Typically, the rate of oxygen replenishment in the shell is lower than the rate normally utilized by the microbial flora and / or microfauna in the open water, which can cause and / or force at least some of the microbial flora and / or microfauna in the shell to change its activity, behavior, reproduction, metabolism, diversity, composition and / or relative distribution to adapt to the artificial conditions in the shell, as well as affecting various natural chemical processes (such as oxidation) and / or the activity of free radicals, etc. Furthermore, as open water oxygen levels and / or exchange rates fluctuate due to various factors (diurnal / night cycles, tidal / ebb flows and / or other water movements, water aeration due to wind and / or storm activity, etc.), the influx of dissolved oxygen will vary, which alters the levels of oxygen and / or other chemicals within the enclosure, thereby causing further changes in the activity, behavior, reproduction, metabolism, composition and / or relative concentrations of the microflora and / or microfauna within the artificial environment within the enclosure. Desirably, the artificial environmental conditions created by the enclosure will thereby inhibit and / or prevent the settlement, recruitment, growth and / or colonization of the substrate by fouling organisms, and will also cause a unique mix of metabolic and / or other processes to occur within the enclosure.

[0258] Although in some embodiments, the housing may substantially surround and / or enclose the outer surface of the substrate, in some alternative applications, the housing may desirably be positioned and / or configured to protect a substrate positioned outside the housing, wherein an "open aqueous environment" may be considered to be positioned within the housing, and a "closed aqueous environment" may be positioned between the outer wall of the housing and the inner wall of the substrate. For example, in a water storage tank or cooling water inlet system, the inner wall of the tank and / or system may constitute the "substrate" to be protected, and some or all of the water pumped into the tank or system may constitute the "open aqueous environment" from which protection of the substrate is sought. In such cases, a housing as described herein may be positioned around the water inlet (or the housing wall may be positioned at some point between the water inlet and the tank wall), wherein the housing desirably creates one or more "different" environmental conditions proximate to the tank wall, and protects the tank wall and / or other internal structures (i.e., heat exchanger tubing) from the various effects of biofouling as described herein.

[0259] If desired, one or more of the shell walls may include perforations and / or penetrations in the wall, which may include perforations and / or penetrations of different sizes for use at different depths along the shell wall. For example, the shell wall may include no perforations or very small perforations at shallower layers of the wall, wherein larger perforations are formed in the same wall at the level of deeper layers of the wall, wherein each wall section includes the same and / or different perforation sizes at the same or different depths of the water column.

[0260] In various embodiments, the dissolved oxygen level within each enclosure embodiment will generally be lower than the dissolved oxygen in the surrounding open water, thereby creating an artificial environment that causes the microflora and / or microfauna within the enclosure to change their activity, behavior, reproduction, metabolism, diversity, composition and / or relative distribution to adapt to these artificial conditions. In addition, these artificial conditions within a given enclosure may be constantly changing, such as the dissolved oxygen level within the enclosure "following" or "lagging" changes in oxygen levels outside the enclosure.

[0261] Typically, changes in the net amount of dissolved oxygen within an enclosure as described herein will be due to any influx of dissolved oxygen contained in water flowing through the enclosure wall into the enclosure and / or any other enclosure opening (i.e., generally increasing the oxygen supply), minus the amount of oxygen consumed within the enclosure (i.e., reducing the oxygen supply) by various processes occurring within the enclosure (including oxidation processes or the like and / or metabolic processes of the flora and / or fauna therein) (and to some extent any flow of dissolved oxygen in deoxygenated water flowing out of the enclosure). The net oxygen level in the enclosure will increase to some extent in the event that the external dissolved oxygen level is high and / or the influx of water brings more oxygen into the enclosure than is consumed within the enclosure and / or leaves the enclosure, and will decrease to some extent in the event that the external dissolved oxygen level is low and / or when the influx of water is slow and brings less oxygen than is consumed within the enclosure. Thus, the dissolved oxygen level within the enclosure "reacts" or "lags" the dissolved oxygen level of the water surrounding the enclosure, with the enclosure DO level typically (but not necessarily always) being lower than the DO of the surrounding water. Additionally, DO levels within a properly constructed and applied enclosure will typically mimic diurnal and / or seasonal fluctuations in dissolved oxygen outside the enclosure, but at lower levels. Each of these changes in the differentiated environment will desirably cause the macrofouling and microbial flora and / or macrofouling and microfauna within the enclosure to further alter their activity, behavior, reproduction, metabolism, diversity, composition, and / or relative distribution to adapt to the changes in the artificial environment.

[0262] In addition to generally induced lower dissolved oxygen levels within the enclosure than those induced outside the enclosure, various embodiments of the present invention can reduce and / or limit the amount of variation between the highest and lowest oxygen levels in the open environment, and additionally have the ability to reduce or "eliminate" many of the transient variations in oxygen levels that can cause scaling in the open environment. The desired buffering or smoothing of DO levels within the enclosure will accommodate variations in dissolved oxygen within the enclosure as compared to the more "jagged" and / or abrupt DO level variations in the open environment outside the enclosure.

[0263] In various housing embodiments, dissolved oxygen levels within the local aquatic environment will desirably be maintained at an average level over a 24 hour period, or above 5%, or 8%, or 10%, or 12%, or 15%, or 20%, or 25%, or 50%, or 60%, or 75%, or 80%, or 85%, or 90%, or 100%, or 105%, or 110%, or 115%, or 120% or 125% concentration or above other dissolved oxygen levels (including above 15%, above 14%, above 13%, above 12%, above 11%, above 10%, above 9%, above 8%, above 7%, above 6%, above 5%, above 4%, above 3%, above 2%, above 1% and / or above 0% dissolved oxygen). However, in some embodiments, it is acceptable and / or even desirable to reduce the dissolved oxygen level within the enclosure to anoxic levels, which may include an oxygen concentration of less than 0.5 mg of oxygen per liter of liquid within some or all of the enclosures. Such anoxic conditions will desirably not be maintained for an extended period of time, but rather tend to be a relatively short-lived phenomenon lasting less than one minute, or less than 10 minutes, or less than half an hour, or less than an hour, or less than 3 hours, or less than 12 hours, or less than 24 hours, or less than a week, depending on the relevant enclosure design, local water conditions, the substrate to be protected, one or more relevant seasons, local scaling pressures, and / or other factors. Desirably, such reduced and / or anoxic oxygen levels will not be maintained for a period of time that would be significantly detrimental to the underlying substrate and / or the structure of the enclosure.

[0264] In various embodiments, the reduced dissolved oxygen levels generated within the enclosure will significantly help reduce biofouling of the substrate, as the reduced oxygen availability may make it difficult for some structural organisms to colonize and / or thrive within the enclosure and / or on the substrate. Additionally, the reduction in dissolved oxygen levels within the enclosure may increase the production of other organisms and / or significantly reduce other biological processes and / or elimination of nitrogen such as hydrogen sulfide and / or ammoniacal nitrogen (i.e., free ammonium nitrogen, nitrogen-ammonia, or NH4+). 3-N) and other waste materials, which are harmful and / or even toxic to a variety of aquatic organisms and / or microorganisms. For example, the biologically driven nitrogen cycle occurring in various water bodies can greatly reduce the free oxygen in the shell, where NH 3 -N levels depend at least in part on the available dissolved oxygen levels. Additionally, in some embodiments, anaerobic ammonium oxidation reactions may be initiated and / or sustained by bacteria within the enclosure, which may produce hydrazine and / or other byproducts that similarly inhibit marine growth. Typically, the concentrations of these byproducts are greater inside the enclosure than outside the enclosure (although various of these harmful compounds - including various known and / or unknown microbial "toxins" and / or inhibitory compounds - may elute through the enclosure wall at different rates), and in some embodiments, the individual concentrations and / or comparative ratios of these byproducts within the enclosure may fluctuate for various reasons.

[0265] For example, in various embodiments, the shells described herein can cause metabolic waste products, toxins, or other inhibitory compounds (such as NH 4+, ... 3 -N) is produced within the enclosure, and the metabolic waste products, toxins, or other inhibitory compounds may be toxic to various freshwater organisms (usually depending on pH and / or temperature). In other embodiments, the NH generated in the differentiated environment within the disclosed enclosure 3 The concentration of -N can be in the range of 0.053 to 2.28 mg / L, which can inhibit the formation of biofouling inside the housing and / or on the outer surface of the housing. 3 At -N levels as low as 0.002 mg / L or higher, the ability of various aquatic flora and / or fauna to colonize and / or reproduce may be significantly degraded.

[0266] It is further suggested that in some exemplary embodiments, fluctuations and / or changes in individual levels of water chemistry within the enclosure, such as dissolved oxygen, ammonium, total dissolved nitrogen, nitrates, nitrites, orthophosphates, total dissolved phosphates, and / or silica (as well as various other components of the chemical composition described herein), form an important aspect of some embodiments of the present invention, as the artificial environment created within the enclosure will desirably "promote" and / or "inhibit" the proliferation of different macrofouling and microbial flora and / or macrofouling and microfauna at different time periods. Such continuous changes in the differentiated environment desirably force the various organisms present within and / or near the enclosure to constantly adapt and / or change to accommodate new environmental conditions, which tends to inhibit the dominance of a single species or population within and / or near the enclosure. This can have the effect of enhancing competition between the various flora and / or fauna within the enclosure, which can inhibit and / or prevent domination of the enclosure by a single type, species and / or distribution of flora and / or fauna and thereby reduce the likelihood that a dominant species of bacteria or other microscopic or macroscopic entities will have the opportunity to thrive and / or invest energy in contaminating the substrate or forming a basis for the attachment of other fouling organisms.

[0267] In various embodiments, the housing can cause the formation of water chemistry factors that inhibit scaling, such as ammonia nitrogen, at a concentration within the housing that is higher than the concentration outside the housing. If desired, an ammonia nitrogen concentration can be obtained within the housing, which can be equal to or greater than 0.1 parts per billion (ppb), can be equal to or greater than 1 part per billion (ppb), can be equal to or greater than 10 parts per billion (ppb), and / or can be equal to or greater than 100 parts per billion (ppb). In various embodiments, the housing can cause the formation of water chemistry factors that inhibit scaling, such as nitrite, at a concentration within the housing that is higher than the concentration outside the housing. If desired, nitrite can be obtained within the housing, which can be equal to or greater than 0.1 parts per billion (ppb), can be equal to or greater than 0.1 parts per million (ppm), can be equal to or greater than 0.5 parts per million (ppm), and / or can be equal to or greater than 1 part per million (ppm).

[0268] In many embodiments of the present invention, another important aspect on the shell is that the shell is expected to suppress but not completely prevent water from flowing into and / or flowing out of the shell under typical water conditions. In many cases, the substrate to be protected will be fixed, connected, attached and / or tethered to one or more immovable solid objects, such as seabed, anchor, wall, pier, pile, pier, spindle plate or other structure, and the one or more immovable solid objects can limit the movement of the substrate to varying degrees relative to the water in which it is located, which can cause a large amount of water of a certain level to flow through each surface of the substrate. However, each embodiment of the shell described herein (usually attached to the substrate, its various supporting structures and / or other adjacent objects) will be expected to interrupt and / or hinder the water flow around the substrate surface to a certain extent, and will more expected to maintain closed or bounded water bodies in direct contact with the substrate under many water flow conditions. Various shell designs disclosed herein achieve this purpose by the flexibility of various shell components, and the flexibility allows the shell and the closed or bounded water bodies therein to deform and / or shift to varying degrees in response to the impact and / or movement of surrounding water.

[0269] In various embodiments, placing the housing in an aqueous medium surrounding the substrate will desirably "regulate" the dissolved oxygen and create a dissolved oxygen differential between the water inside and outside the housing, which desirably provides significant improvements in preventing fouling of the protected article. In many cases, the dissolved oxygen regulation of the differentiated environment can include generating a much lower dissolved oxygen level in the housing than in the external environment, wherein this dissolved oxygen level in the housing fluctuates to varying degrees in response to internal oxygen consumption and external dissolved oxygen levels. In addition, at least in part due to the lower energy environment in the housing compared to the external environment and / or the absence of significant turbulence and / or eddies that can "mix" the water in the housing, there may also be a secondary gradient between the dissolved oxygen in the "bulk water" in the differentiated environment and the dissolved oxygen in the water in the "boundary layer" at the surface of the protected substrate or article. These local differential conditions may be caused by the consumption of oxygen and / or nutrients by organic matter and / or other factors on the surface of the substrate or article and / or in the water column within the housing, which may lead to further depletion of the "boundary layer", which promotes the lack of biofouling and / or the formation of antifouling biofilms on the protected articles.

[0270] Generally, 100% DO ("dissolved oxygen") means that the water contains as many dissolved oxygen molecules as possible at equilibrium, while more than 100% DO means that the water is "supersaturated" with oxygen (which often occurs in seawater due to the effects of photosynthesis, atmospheric exchange, and / or temperature changes). At equilibrium, the proportion of each gas in the water can approximate the proportion of each gas in the atmosphere but is rarely the same as the proportion. Therefore, at equilibrium, the percentage of oxygen in the water (compared to other gases in the water) can be equivalent to the percentage of oxygen in the atmosphere (compared to other gases in the atmosphere). However, the specific concentration of dissolved oxygen in a body of water generally varies based on temperature, pressure, salinity, and other factors (such as photosynthetic availability and / or surface agitation). First, the solubility of oxygen decreases with increasing temperature. Therefore, warmer water contains less dissolved oxygen than colder water at 100% saturation, and therefore colder water can carry more oxygen. For example, at sea level and 4°C, 100% air-saturated water will hold 10.92 mg / L of dissolved oxygen. However, if the temperature is raised to room temperature of 21°C, at 100% air saturation, there is only 8.68 mg / L DO. Second, dissolved oxygen increases with increasing pressure. Deep water can hold more dissolved oxygen than shallow water. Due to hydrostatic pressure, the gas saturation decreases by 10% for every additional meter of depth. Therefore, if the concentration of dissolved oxygen is at 100% air saturation at the surface, the dissolved oxygen concentration three meters below the surface is only at 70% air saturation, even if the same amount of oxygen is available for biological needs. Third, dissolved oxygen decreases exponentially as salt levels increase. Therefore, at the same pressure and temperature, salt water holds about 20% less dissolved oxygen than fresh water. In addition, because the above factors have changed (for example, the air or water temperature may change during the day) and may not have reached equilibrium, the dissolved oxygen at any specific time may not be in equilibrium with the environment. Additionally, wind and other agitation of the water may cause aeration of the water beyond that expected under ambient conditions, and local oxygen use and / or generation by biological and / or other processes may continually increase or decrease the amount of dissolved oxygen.

[0271] In various embodiments, once the housing described herein is placed around a substrate in an aqueous environment, the dissolved oxygen in the housing will desirably be utilized by various naturally occurring organisms and / or other processes, causing the local dissolved oxygen level within the housing to begin to change relative to the dissolved oxygen level in the water outside the housing. Since the permeability transport of dissolved oxygen in water occurs very slowly, and since there is typically little or no sunlight energy streaming into the housing to allow oxygen to be produced by photosynthesis, the primary source of additional dissolved oxygen entering the housing is typically from water outside the housing that is transported in large quantities into the housing through openings in the housing walls and other components (typically transporting dissolved oxygen at a higher percentage). This additional dissolved oxygen is then utilized within the housing in a manner similar to that previously described, wherein this cycle is continually repeated until the dissolved oxygen level within the housing typically reaches a stable level that is typically above the anaerobic level, but also significantly below the oxygen level outside the housing.

[0272] In various embodiments, the dissolved oxygen level within the enclosure can be consistently lower than the open water readings surrounding the enclosure, thereby creating a "different environment" compared to the surrounding aqueous environment. However, because the various enclosures allow for various levels of "fluid exchange" with the external aqueous environment, many other characteristics of the overall water quality within the enclosure (including pH, temperature, and salinity) can be the same or similar to those of the surrounding aqueous environment. However, because natural oxygen levels typically fluctuate over a 24-hour period (i.e., oxygen levels outside the enclosure typically fluctuate in a diurnal manner—wherein dissolved oxygen levels are higher during the day due to photosynthesis, and dissolved oxygen levels drop during the night period), within the enclosure, dissolved oxygen levels within the same 24-hour period will typically fluctuate in a manner similar to levels outside the enclosure, because the amount of "dissolved oxygen replacement" transported into the enclosure by bulk fluid will vary depending on the external dissolved oxygen level. In some cases, such as when the oxygen level outside the enclosure is low, the oxygen level inside the enclosure may be higher for a limited period of time. Furthermore, because displaced dissolved oxygen enters the enclosure near the enclosure walls and bulk movement and / or mixing of water within the enclosure is often restricted, a higher or lower dissolved oxygen gradient typically exists between the enclosure walls and the surface of the protected substrate.

[0273] In many cases, the enclosures described herein may desirably control, mitigate, and / or "smooth" one or more dissolved oxygen levels in a differentiated aqueous environment (i.e., proximate to the protected substrate) as compared to the DO level of water in the surrounding open aqueous environment. In many cases, the DO level within the enclosure will desirably be below the DO level of the surrounding aqueous environment, although the differentiated DO level may periodically exceed the DO level of the surrounding open aqueous environment in some embodiments and / or some conditions. Additionally, while periodic and / or intermittent differentiated DO levels that fall within the anoxic range may be acceptable in various circumstances, including circumstances where the anoxic period is short enough to allow little or no anoxic corrosion of the substrate, the enclosures described herein will desirably maintain the differentiated DO level above the anoxic DO level.

[0274] In various embodiments, dissolved oxygen levels of 0.5 mg / L or less may be considered undesirable and / or "anoxic" conditions, while dissolved oxygen levels of approximately 2 mg / L (or less) can have a significant negative impact on the ability of aquatic organisms to colonize, reproduce, and / or thrive in an aquatic environment.

[0275] In many cases, significant changes in the dissolved oxygen content of a given aqueous environment may cause a rapid response from many organisms, with downward changes in DO levels being one of the parameters to which organisms respond most quickly. The broad classification of bacteria or other organisms as anaerobic, aerobic, or facultative is generally based on the type of reaction that the bacteria or other organisms use to generate energy for growth and other activities. In their metabolism of energy-containing compounds, aerobic bacteria require molecular oxygen as a terminal electron acceptor and are generally unable to grow in its absence. On the other hand, anaerobic bacteria are generally unable to grow in the presence of oxygen-oxygen is toxic to them, so the anaerobic bacteria must rely on other substances as electron acceptors. Their metabolism is generally fermentative, in which the anaerobic bacteria reduce available organic compounds to various end products, such as organic acids and alcohols. Facultative organisms are the most versatile. The facultative organisms preferentially utilize oxygen as a terminal electron acceptor, but can also metabolize by reducing other compounds in the absence of oxygen. For example, more available energy is obtained in the form of high-energy phosphates when glucose molecules are completely decomposed into carbon dioxide and water in the presence of oxygen (38 molecules of ATP) than when they are only partially decomposed by a fermentation process in the absence of oxygen (2 ATP molecules). In some cases, a decrease in DO levels within the enclosure may prompt an organism to alter the rate and / or type of its metabolic pathways, which may include adapting to the new DO level, while other organisms may simply enter a state of stasis and / or die. If the DO level of the enclosure environment is undesirably low, the organism will typically seek another environment with a higher DO level to colonize (and / or may attempt to abandon a lower DO environment) because if the organism does not find an increased DO environment, remaining in the lower DO environment of the enclosure may negatively affect the ability to settle and / or may result in various health problems and / or death.

[0276] In various embodiments, the optimal and / or desired DO level within the enclosure may be a DO content that is at least 20% or greater on average, or at least 50% or greater on average, or at least 70% or greater on average, or in the range of 20% to 100% on average, or in the range of 33% to 67% on average, or in the range of 50% to 90% on average, or in the range of 70% to 80% on average. Alternatively, the desired DO level within the enclosure may be a DO content that is at least 10% less than the dissolved oxygen level in the water detected at a distance from the outside of the enclosure (i.e., 1, or 2, or 5, or 10, or 12 inches, or 2, or 5, or 10 feet from the enclosure).

[0277] In various embodiments, the regulation of dissolved oxygen within the housing will cause a difference in dissolved oxygen between the differentiated environment within the housing and the open aqueous environment outside the housing of at least 10%. In various embodiments, this difference may occur within / after a few hours after the housing is placed in the aqueous medium, or may occur within 2 to 3 hours, 6 hours, 12 hours, 1 day, 2 days, 3 days, 4 days, 5 days, 6 days, 1 week, 2 weeks, or even within a month after the housing is placed. In various alternative embodiments, the desired dissolved oxygen difference produced is at least 5%, at least 10%, at least 15%, at least 20%, at least 25%, at least 50%, at least 70%, and / or at least 90% or more.

[0278] In many cases, the level of dissolved oxygen within a given enclosure will be depleted by biological and / or other processes, wherein maintenance of dissolved oxygen levels within various enclosure designs may depend on the influx of dissolved oxygen through the walls of the enclosure from the surrounding aqueous environment (when such DO levels are higher than the DO levels within the enclosure) - which may also occur at some level by diffusion through the wall structure itself and with the bulk transfer of water through the permeable enclosure wall. The structures and methods described herein desirably provide an enclosure having a sufficient level of "water exchange" for providing sufficient water flow (and / or dissolved oxygen flow) into and / or through the structure so as to avoid the creation of an anoxic environment within the enclosure over an extended period of time, which may cause corrosion of metal surfaces, but also desirably create a localized aquatic environment and / or biofilm coating on the substrate that minimizes and / or prevents aquatic organisms from settling and / or thriving on the substrate. Specifically, the devices of the present invention will desirably provide a level of permeability that is intended to maintain dissolved oxygen (DO) levels within a differentiated aquatic environment (i.e., surrounding the object to be protected) at a level that is different from one or more DO levels of the surrounding aqueous environment.

[0279] In one exemplary embodiment, the DO level of an open aquatic environment ranges from about 90% to about 150% DO, while the DO level of a differentiated aquatic environment (i.e., containing the substrate to be protected) can range from about 50% to about 110% DO - this in this embodiment inhibits the ability of various organisms to scale the substrate (which is believed to substantially inhibit and / or prevent their ability to thrive and / or colonize), and this is done without "dipping" over extended periods of time to DO levels where hypoxia may occur and promote corrosion to the substrate (although periodic hypoxic conditions for relatively short periods of time may have occurred and may be acceptable for various reasons). In various embodiments, the presence of the shell may also mediate, "smooth" or "buffer" natural spikes and / or dips that may occur in the dissolved oxygen level of the surrounding aqueous environment, which may further prevent and / or inhibit aquatic organisms from settling and / or flourishing on the protected substrate.

[0280] In at least one alternative embodiment, the housing design may include a wall material that is permeable to one or more water chemistry factors, such as dissolved oxygen (i.e., transported by diffusion and / or osmosis) while not promoting the transport or passage of one or more other factors, chemicals, and / or even water itself, which may allow sufficient levels of oxygen (or other chemical factors) to permeate into the housing to produce some or all of the water chemistry differences described herein. Such alternative designs may have some potential to produce various biofouling improvements disclosed herein.

[0281] In various other alternative embodiments, a particular housing design may include features for replenishing various water chemistry components (e.g., dissolved oxygen) within the housing to obtain desired scaling protection. For example, a housing having walls that are slightly less permeable than an optimal level may include a supplemental source of dissolved oxygen that may be used to maintain dissolved oxygen levels within the housing above undesirable anoxic levels. Alternatively, an embodiment of the housing may include a supplemental fluid supply pump or even an externally mounted "propeller" that may be activated to cause additional fluid external to the housing to pass through and / or enter the housing to provide additional supplemental dissolved oxygen and / or remove waste from the housing, wherein the pump / propeller is activated and / or deactivated periodically and / or based on various measurements taken of water chemistry factors within the housing, which may include water chemistry factors that are directly affected by the housing design and placement, as well as changes in water chemistry factors that may result from one or more water chemistry factors that are directly altered by the presence of the housing. Alternatively, a supplemental pump and / or pumping system may be utilized to pump water directly into and / or out of a closed or bounded body of water without the water passing through the permeable housing walls.

[0282] Instead of and / or in addition to reducing the level of dissolved oxygen in the water contained in the enclosure, the design and placement of the enclosure embodiments described herein may also affect various other water chemistry factors, including water chemistry factors that may significantly delay and / or prevent scaling of the protected substrate. For example, when oxygen is depleted within the enclosure, some naturally occurring bacterial species within the enclosure will typically first turn to a suboptimal electron acceptor, which in seawater is nitrate. Denitrification will occur, and the nitrate will be rapidly consumed. After reducing some other trace elements, these bacteria eventually turn to reducing sulfate, which produces hydrogen sulfide (H2S). 2 The hydrogen sulfide in the enclosure may be a byproduct of the production of hydrogen sulfide (S) (which is chemically toxic to most biota and has a characteristic "rotten egg" odor). This elevated level of hydrogen sulfide, along with other chemicals within the enclosure, may then inhibit scaling of the substrate in the desired manner described herein. In addition, the hydrogen sulfide within the enclosure may also elute through the walls of the enclosure (i.e., where a large amount of water flows out of the enclosure) and potentially inhibit scale growth in the pores of the enclosure and / or on the outer surface of the enclosure.

[0283] In addition to producing local conditions that inhibit the fouling of the protected substrate contained in the shell, each embodiment of the shell described herein is also very environmentally friendly, because any toxic and / or harsh environment produced in the shell will be rapidly neutralized outside the shell. For example, when the fluid of 1ml enters the shell through the opening, it can be assumed that the shell fluid of about 1ml will be replaced from the outside of the shell to the external environment. The fluid of this displacement will usually contain components that are toxic and / or unsuitable for marine organisms (the components are expected to reduce and / or prevent fouling from being attached to the substrate in the shell). However, once leaving the shell, these components will be rapidly degraded, oxidized, neutralized, metabolized and / or diluted in an external aqueous environment by a variety of naturally occurring mechanisms, and the mechanisms will not cause lasting effects on aquatic environments usually, even if they are close to the shell itself. This is highly preferred for existing antifouling devices and / or coatings in combination with high-level biocides and / or other agents, wherein some of the biocides and / or other agents are highly toxic to many life forms (comprising fish and humans and / or other mammals), and can last for decades in marine environments.

[0284] Desired biofilm formation

[0285] As disclosed herein, in the case of using a shell to protect a substrate, the biological colonization sequence on the substrate can be significantly different from the normally expected open water sequence. For example, in the case of using a shell as described herein, the biological colonization sequence on the substrate can be interrupted (destroyed, changed, etc.) to reduce and / or minimize the sedimentation, recruitment and final macroscopic fouling of the substrate. Once positioned around or inside the substrate (for example, if the inner surface of the substrate is protected), the permeable protective fabric wall of the filter medium and / or shell can be expected to filter and / or prevent various microorganisms and / or large microorganisms from entering the shell, and if the organism is already positioned in the shell and / or if the organism eventually passes through the shell, the different water conditions generated between the shell wall and the substrate can prevent some and / or all organisms from settling and / or colonizing on the substrate. For example, when microscopic plankton and other traditional non-settling organisms and other settling organisms pass through the permeable fabric membrane of the shell, different water conditions in the shell may damage or injure some of the plankton in the plankton, while other plankton that are still alive and active will avoid settling and / or colonizing on the substrate surface.

[0286] In various embodiments, initial placement of a biofilm protective enclosure around a substrate may result in and / or cause formation of a "protective" biofilm layer on the surface of the substrate, wherein such biofilm layer has various desirable properties, such as (1) forming a biofilm layer that minimizes interference of the biofilm with heat transfer through the underlying surface and / or (2) forming a biofilm layer that subsequently protects the substrate from significant additional fouling, which may even include providing biofouling protection after the integrity of the enclosure may be compromised and the substrate potentially exposed directly to the external environment.

[0287] In various aspects of the invention, as described herein, proper design and use of the enclosure can create within the enclosure a "different environment" that influences and / or causes the formation of a biocoating, layer, and / or biofilm on the surface of a substrate, the different environment being effective in reducing and / or preventing the settlement of biofouling organisms on the substrate. In some aspects of the invention, such reduction and / or prevention may be due to one or more localized settlement cues that prevent (e.g., reduce, minimize, or prevent) larval settlement of the biofouling organism, which may include preventing settlement on the substrate, while in other aspects of the invention, the reduction and / or prevention may be due to the absence of one or more positive settlement cues that promote larval settlement of the biofouling organism, which may similarly reduce settlement on the substrate (and / or various combinations of the presence and / or absence of settlement cues may relate to various embodiments). In another aspect of the invention, the enclosure may promote the growth of microorganisms that produce one or more localized settlement cues that prevent the settlement of larvae of the biofouling organism within the differentiated aquatic environment created by the enclosure. In another aspect of the invention, the shell can promote the growth of microorganisms that produce one or more localized settlement cues that prevent larvae of biofouling organisms from settling onto and / or into the shell material itself. Thus, in these aspects of the invention, larvae of biofouling organisms may be unable or less likely to settle or attach to the submerged substrate or one or more substrate portions protected by the shell.

[0288] In various embodiments, the biofilm may be formed on the protected substrate, may be formed on the exterior of the enclosure and / or the interior of the enclosure. The biofilm may be different at each location based on the amount of bacteria, cyanobacteria, diatoms, different bacterial phyla, diversity, thickness, insulating ability and / or integrity, and other metrics.

[0289] There are a number of generally accepted "standard" progressions or colonization sequences that typically result in the establishment of a fouling community on a substrate immersed in an aqueous medium such as seawater, saltwater and / or freshwater. In a typical sequence, immersion of the substrate in an aqueous medium immediately initiates the physical process of macromolecular adsorption, followed by rapid landing, attachment and colonization of prokaryotic cells and bacteria on any surface in the marine environment. In some cases, the subsequent formation of a microbial biofilm may then promote the attachment of algal spores, protozoa, barnacle algae and marine fungi, followed by the settlement of other marine invertebrate larvae and macroalgae, while in other cases, macrofouling species may settle in the absence of a biofilm and some other macrofouling species may prefer clean surfaces.

[0290] Marine fouling is usually described as four stages of ecosystem development. The chemistry of biofilm formation describes the initial steps before colonization. In the first minute, van der Waals interactions cover the submerged surface with a conditioning film of organic polymers. In the next 24 hours, this layer allows bacterial attachment processes to occur, where both diatoms and bacteria (e.g., Vibrio alginolyticus, Pseudomonas putrefaciens) attach, thereby beginning to form biofilms. By the end of the first week, the enriched nutrients and the ease of attachment to the biofilm allow secondary colonizers of macroalgae spores (e.g., Enteromorpha enterica, filamentous algae) and protozoa (e.g., bell worms, polycystic ovary) to attach. In 2 to 3 weeks, tertiary colonizers - macroscopic fouling - attach. These include tunicates, molluscs and sessile coelenterates.

[0291] However, in the case of utilizing an enclosure as described herein, the biological colonization sequence on the substrate can be varied. For example, the biological colonization sequence on the substrate can be interrupted (destroyed, altered, etc.) to reduce and / or minimize the sedimentation, recruitment, and ultimate macro-fouling of the protected substrate. Once positioned around the substrate, the permeable protective fabric wall of the enclosure can desirably filter and / or prevent various microorganisms and / or macro-organisms from entering the enclosure, as well as potentially altering various aspects of the water chemistry within the enclosure.

[0292] Fig.24 The distribution of various bacterial phyla in biofilms formed on substrates of open samples (six bars on the far left) and substrates within various enclosure embodiments in seawater (six bars on the far right) is graphically depicted, with Table 6 (below) containing the underlying data as shown. Fig.24Depicted. The bacterial biofilm formed on the substrate or other article protected by the shell is significantly different from any natural biofilm formed on the substrate or other object in the open sea or other aqueous environment near the protected article. In various embodiments, the appropriate design and operation of the shell will desirably cause and / or promote the growth and replication of certain microbial combinations, many of which are typically found in natural environments at different (i.e., often relatively low) levels, and the combination of these microorganisms may have the ability to promote certain "recruitment and settlement" behavior to other organisms, identifying the substrate surface as unsuitable and / or "less desirable" (and indicating this fact in a variety of ways).

[0293] DNA analysis confirmed that the surface biofilms formed on the PVC and bronze substrates inside the various protected enclosure embodiments were significantly different from the biofilms formed on similar substrates outside the enclosure, and this was also true for the biofilm-forming communities present within the enclosure and the biofilms formed in / on the inner wall surface of the enclosure. For example, the biofilms that appeared on the PVC and bronze article samples in open water were thicker and more diverse than the biofilms that appeared on the PVC and bronze article samples protected by the enclosure of the present invention. In addition, macroscopic fouling was observed on the articles in the open water; while there was little or no macroscopic fouling on the substrates protected by the enclosure. In some embodiments, the biofilm diversity on the closed substrate was less than that of the open biofilms with different amounts of diatoms, bacteria, cyanobacteria, and distribution of different bacterial phyla. In addition, for each enclosure design, the dominant bacterial phyla and bacterial distribution within each enclosure (and / or on each substrate) were significantly different. For example, as shown in Fig.24 As best seen in the Figure 6 and supported by the data in Table 6, the PVC substrates within the spun polyester shell (three rightmost bars) were dominated by Proteobacteria (grouping at the top of the bar) and Bacteroidetes (second largest grouping at the bottom of the bar). In contrast, the bronze substrates within the spun polyester shell (bars 6 to 9) were dominated by Proteobacteria, with the remainder dominated by Bacteroidetes. The distribution map of the dominant bacterial phyla in the biofilm applies to the open bronze bars (first to third columns), the open PVC bars (fourth to sixth columns), the closed bronze bars (seventh to ninth columns), and the closed PVC bars (tenth to twelfth columns). In addition, the biofilm "integrity" of the closed substrates was different from the open samples, as the biofilm on some of the closed substrates appeared to be easier to remove and / or clean from the substrate surface than on the open substrates.

[0294]

[0295] Table 6 - Distribution of bacterial phyla in biofilms

[0296] In a number of experiments, various substrates were immersed in an aqueous environment (i.e., natural seawater), wherein some of the substrates were protected by enclosure designs (such as those described herein) over a three week period of immersion, at which point the substrates were removed from the seawater and the enclosures and resulting substrate surface biofilms (which had formed on these substrates during the time period) were subjected to DNA analysis. Visual comparison between bronze substrates protected by enclosures and unprotected (i.e., open) bronze substrates depicted a significant reduction in fouling organisms on the protected substrates. Furthermore, it was demonstrated that the biofilms formed on the open strips (i.e., unprotected PVC and bronze) were significantly thicker than those on the protected substrates. Additionally, a significant difference between the biofilms of the open and differentiated samples was the predominant presence of Proteobacteria and Bacteroidetes in the biofilms of the protected substrates, and the near absence of Verrucomicrobia and Actinomycetes in the protected biofilms. It is believed that the predominant presence and / or absence of various bacteria in the novel and / or "artificial" or "synthetic" biofilms formed on the substrate within the artificial "differentiated" environment created by the novel shell is a unique and significantly different artificial biofilm that produces different (and potentially unfavorable) settling cues compared to those normal settling cues presented by naturally formed biofilm layers in open aquatic environments, thereby reducing the chance of substrate settling and / or colonization by microfouling and / or macrofouling agents even in the absence of the shell (i.e., after the shell is permanently and / or temporarily removed).

[0297] In another experimental test, a series of transparent glass substrates were immersed in an aqueous environment and analyzed to determine the thickness and type of biofilm / fouling formed on substrates protected and unprotected in novel enclosure designs (such as those described herein) over a thirty-day, eight-month, and twelve-month period. These test results concluded that no macroscopic fouling sedimentation occurred on the slides inside the novel enclosure throughout the 30-day test period. In contrast, slides placed in open water continued to accumulate macroscopic fouling on the 30th day. The macroscopic fouling on the open slides consisted of hydrozoans, crustaceans and dendritic bryozoans, barnacles, tube worms, and sponges, and from the 14th day on, the sedimentation on the open slides was significantly higher.

[0298] Regarding biofilm on various substrates, it has been determined that the unique biofilm on the slide from the inside of the protective housing is so thin that it is not easy to see, and the presence of the biofilm is indicated by a small adherent sediment mass. From the 1st day to the 30th day, the biofilm appearance in these protected slides is almost unchanged. On the contrary, after being immersed in salt water for 30 days, the open slide biofilm has changed significantly during the whole experiment. On the 1st day, the biofilm is very light and similar to the differentiated biofilm. However, by the 3rd day, the open biofilm is dominated by the peritrichous ciliates (predatory ciliates that feed on biofilm). On the 7th day, the visible part of the open biofilm is composed of diatoms, cyanobacteria and microalgae and microscopic motile organisms (ciliates, flagellates, etc.) that feed on fixed biofilm organisms. These unprotected biofilms are even thicker and more developed on the 14th day, and filamentous algae have accumulated. Additionally, the dissolved oxygen levels in the open water were significantly higher than those in the novel enclosure on days 1, 7, and 14. Furthermore, after day 14, the liquid pH in the open water was significantly higher than that in the novel enclosure.

[0299] After one year of immersion in salt water, glass substrates protected with fabric antifouling shells were examined for biofouling. After 12 months of immersion, no major or minor biofouling or settlement of organisms occurred on the protected glass substrates; however, biofilms were formed on the glass substrates protected by the fabric shells. The biofilms for this 12 month ranged from patchy, fragmented, discontinuous thin layers on some substrates to continuous, thin film layers that extended completely across the surface on other substrates. Compared to the biofilms on the glass substrates after 30 days, these 12 month biofilm structures were more developed and complex; however, the biofilms on the unprotected glass substrates after 30 days were exponentially more developed, complex, and thicker than the biofilms on the protected glass substrates after 12 months. After 12 months, there were no cyanobacteria or diatoms in the biofilms on the protected glass substrates, except for a few trapped (but not settled) central diatoms. The structure of the 12-month biofilms on the protected glass substrates contained sludge entrapped by extracellular polymeric substances (EPS) and also contained low coverage of tube worms (spirorbids and hydroids) on some glass substrates.

[0300] There are a variety of larval and / or other settlement cues ranging from physical to biochemical. These cues indicate the presence of habitats that are favorable or unfavorable for settling larvae. Physical cues can include light and color, current direction and speed, oxygen, orientation, texture, sound, and surface energy / wettable settlement. Other cues indicating the presence of predators or superior competitors may inhibit settlement. Existing scaling may enhance or inhibit settlement, and the effect may vary according to existing species and settlement species. For the purposes of this disclosure, local settlement cues may mean current conditions and historical markers in a local aquatic environment, which provide information that promotes or prevents (including the absence of promotion) settlement in a local aquatic environment to the larvae of aquatic organisms. In aspects of the present invention, the shell is combined with a substrate and / or a differentiated aquatic environment to define a local aquatic environment, and the local aquatic environment produces and / or promotes the production of local settlement cues that do not promote and / or actively prevent the settlement of aquatic organisms on the substrate and / or on / in the shell. In various embodiments of the present invention, a novel housing or one or more other devices is provided that induces, promotes, enables and / or facilitates the formation of at least one exogenous localized deposition cue.

[0301] It can be expected that once there is or establishes a biofilm or other layer with or without local sedimentation clues, after the shell is no longer engaged with the substrate or removed from the substrate, these clues may be retained for a period of time with the substrate / on the substrate (for example, the surface fully protected by the shell). For example, once the local sedimentation clue is associated with the substrate or is present on the substrate, the shell can be removed and / or damaged, and at least a portion of the local sedimentation clues should continue to exist on the substrate to provide a continuous signal to prevent and / or not promote the sedimentation of macroscopic fouling organisms. As an example, after removing (and / or damaging) the shell, this preventive effect of the local sedimentation clue may remain on the hull, and may continue to prevent sedimentation. This prevention of sedimentation may extend up to about two (2) years, at least 1.5 years, at least 1 year, at least 9 months, at least 6 months, at least 3 months, at least 1 month, at least 1 week, at least 3 days, at least 1 day and / or at least 12 hours. In addition, the biofilm or one or more other layers produced thereon may resist removal and, therefore, may provide continued protection for movable and / or mobile submerged and / or partially submerged surfaces and / or items (including items used to generate propulsion, such as propeller blades and / or shafts). Thus, the housings described herein and the processes of the invention may allow for "inoculation" of substrates to prevent biofouling, which inoculation may continue for a period of time due to the continued action of localized settling cues (LSCs).

[0302] In various embodiments, it is proposed that changes in water chemistry (including all parameters measured) may be due, at least in part, to the accumulation of biofouling organisms on the outer surface, inner surface, or within the fabric of the enclosure structure. In one embodiment, an external biofilm formed on the outer surface of the enclosure structure accumulated and was evident at day 13, with maturity and formation of an organized structure at day 30. At these time points (days 13 and 30), the dissolved oxygen and pH inside the enclosure structure dropped significantly. It is believed that in some exemplary embodiments, dissolved oxygen and pH can be linked together because it can be expected that microbial respiration within the enclosure structure results in a decrease in oxygen and a relative increase in carbon dioxide. An increase in carbonic acid in the water can lead to more acidic conditions, thereby lowering the pH in the water.

[0303] In some embodiments, biofilm components can be used as cues to appropriate settlement sites. Further, the receptors for bacterial cues of invertebrate larvae may be unique for each organism. For many organisms, settlement occurs in response to surface biofilms. The difference between the biofilm on the substrate surface and the biofilm on the shell surface may cause the organism to settle on one biofilm, but not on the other. Preferably, settlement will occur on the biofilm on the shell surface, but not on the biofilm on the substrate surface.

[0304] In at least one additional embodiment, one or more biofilms on the surface of the enclosure structure may act as a "biofilter" and / or utilize or consume nutrients (i.e., oxygen, nitrogen, carbon, phosphates, etc.) and thus not allow some or all of the nutrients to pass through or migrate into the water inside the enclosure structure, which may be confirmed if water chemistry data indicates that more respiration or uptake of nutrients occurs in the open water compared to the enclosed water within the structure. These two communities (bacterial biofilms growing within the fabric and invertebrate macrofouling growing on the exterior surface of the structure) may be responsible for establishing and maintaining a fixed film barrier that provides antifouling protection - at least one mechanism that can prevent biofouling from occurring within the chamber enclosed by the structure.

[0305] In another embodiment, one or more biofilms can be grown on the surface of the shell structure to protect the substrate and extend the life of the shell. These protective biofilms can be positioned on the outer surface of the shell, on the inner surface of the shell, or can be penetrating or in one or more walls of the shell. In certain embodiments, the three-dimensional multifilament textile shell structure can provide a significantly more effective contact surface area than a flat surface, and therefore, the biofilm resident thereon can be significantly more active and / or can be optimized to provide higher protection.

[0306] Table 7A and 7B describe the experimental permeability results of various fabrics and coated fabrics after immersion in pre-soak conditions and in aqueous environments (i.e. seawater) for 23 days. From Table 8B it can be seen that the permeability of the hessian test sample is significantly lower than that of spun polyester. However, both hessian and spun polyester are similar to antifouling fabrics at least partially by excluding larger larvae macroscopic organisms from the environment of the substrate. In various cases, the fabric permeability can be reduced according to the time relevant to surface fouling and / or other fabric degradation. An important result of this test is that due to the degradation of hessian and / or other properties and the production difficulties (such as discoloration, cleaning, sterilization and / or pollution of production equipment) (i.e., natural fibers may need more extensive and more frequent equipment cleaning than synthetic materials during processing), spun polyester may be a more preferred material than hessian (may be less preferred, but still acceptable for various applications).

[0307]

[0308] Table 7A: Sample Pre-soak Penetration of Coated / Uncoated Fabrics

[0309]

[0310] Table 7B: Permeability of coated / uncoated fabrics 23 days after immersion (seawater)

[0311] In various alternative embodiments, the shell wall can incorporate a supplemental biocide or one or more other chemicals or compounds that can inhibit and / or prevent scaling on the shell surface and / or in the pores. In various embodiments, the biocide or one or more other chemicals / compounds can be applied and / or incorporated so that the primary bactericidal activity is limited to the surface and / or in the pores of the shell fabric, with minimal and / or non-existent levels of biocide elution into the shell and / or outside the shell. In such cases, the biocide will desirably protect the shell from scaling, and the shell in turn protects the substrate from scaling.

[0312] Under various daily and / or seasonal water conditions, various test housing designs were very effective in providing biofouling containment for substrates. For various tests, structures or housing embodiments of different sizes and / or shapes were tested to determine whether the presence of the housing reduced, reduced, eliminated, inhibited and / or prevented macroscopic fouling settling, including visual comparison of biofilms formed in the housing compared to open water, and comparing water quality and water chemistry in the housing to open water. Table 8A describes the results of the salt water test in tabular form, and shows that ammonium, nitrate+nitrite (N+N), total dissolved nitrogen (TDN), dissolved organic nitrogen (DON), phosphate and silica are all significantly different between the housing and open samples at different points during sampling, wherein Table 8B describes other chemical measurements, such as temperature, salinity, dissolved oxygen and pH. The test results showed that ammonium was significantly higher in the shell at day 14 (6 / 22 / 18) and day 30 (7 / 9 / 18), and N+N was significantly higher in the shell at day 1 (6 / 9 / 18), day 3 (6 / 11 / 19), and months 10 (4 / 15 / 19), and 12 (6 / 24 / 19). TDN and DON were significantly higher in the open sample at day 7, but shifted and were higher in the shell at day 14 and 30. Phosphate was significantly higher in the shell at days 3, 7, 14, and 30, and months 10 and 12. Silica was significantly higher in the open sample at day 1, 3, and 14, but higher in the shell at day 30.

[0313]

[0314] Table 8A: Water Chemistry Results for Brine in Housing ("Pack") and Open Water

[0315]

[0316] Table 8B: Additional Water Chemistry of Brine in Housing ("Pack") and Open Water

[0317] Various conclusions emerged from the data, including: (1) by day 7, dissolved inorganic nitrogen (N+N and ammonium) was higher in the shell, while dissolved organic nitrogen (amino acids, urea) was higher outside the shell. This could indicate greater biological activity outside the shell, where bacteria, cyanobacteria, and phytoplankton use inorganic nitrogen for growth and produce organic nitrogen (through decay and excretion). The biofilm results from this experiment (based on observations) and DNA results from previous testing confirm this hypothesis. Throughout the second half of the experiment, total dissolved organic nitrogen (DON) within the shell remained similar, while open DON fluctuated, which could be due to natural cycling of nitrogen in the harbor that is sequestered or buffered by the shell, (2) phosphate levels were higher in the shell than in the open water, which could be due to greater biological activity outside the shell that uses phosphorus, and / or (3) silica levels were higher outside the shell by day 14, which could be due to greater activity and turnover of diatoms outside the shell, which shifted by day 30. Total silica levels in the shells were reasonably similar over time, while open levels fluctuated. Since diatoms use silica, this variability may indicate cycling in the open water - cycling that is isolated or buffered by the shells.

[0318] In another example, water chemistry and water quality were observed in various enclosure embodiments. The purpose of the salt water test was to examine the differences in water chemistry between the water within various sizes of enclosures (1, 2, and 4' in diameter) and the open water. Table 8C describes the results of the 12 month salt water test in tabular form and shows that ammonium, nitrate + nitrite (N+N), total dissolved nitrogen (TDN), dissolved organic nitrogen (DON), phosphate, silica, and alkalinity were all significantly different between the enclosure and the open samples at different points during the sampling period, with Table 8D describing additional chemical measurements such as temperature, salinity, dissolved oxygen, and pH.

[0319]

[0320] Table 8C: Water chemistry results for housings ("1', 2', 4'") and brine in open water.

[0321]

[0322] Table 8D: Additional water chemistry of the housings ("1', 2', 4'") and brine in open water.

[0323] The test results show that for all sizes of shells (1, 2 and 4' diameter), the dissolved oxygen and pH in the open water are significantly higher than in the water in the shell. Compared with the open water, the N+N, TDN, phosphate and silica in the waters in the shell are all significantly different. Compared with the open water, the alkalinity, N+N, TDN and phosphate in the shell are all significantly higher. This data shows a trend similar to other water chemistry tests in salt water. Compared with open water, the increase in water chemistry concentrations in the shell can indicate that the biological activity outside the shell is higher, where bacteria, cyanobacteria and phytoplankton can use available nutrients to grow.

[0324] Additionally, some of the results from these water chemistry studies suggest that various enclosure structure embodiments may produce an effect where respiration or material metabolism is greater than or exceeds photosynthesis within the enclosure structure. This effect may occur due to reduced levels of dissolved oxygen or other water chemistry parameters produced by the enclosure structure. Differences in dissolved oxygen within the enclosure may be related to light limitation within the enclosure.

[0325] The effect of respiration over photosynthesis within the shell structure can be confirmed based on the results for phosphate. Phosphate concentrations in the shell waters were consistently higher than in the open water. Based on the phosphate cycle, and knowing that phosphate is exchanged between the particulate and dissolved phases, diffusion may attempt to restore the water chemistry balance on both sides of the permeable shell. The greater the difference in water conditions within the shell structure compared to open water conditions, the greater the effect that diffusion generally has in restoring balance. Therefore, phosphate may continue to increase in the shell waters, but may be lost due to diffusion.

[0326] In one embodiment, the shell structure provides antifouling protection within its scope by initially establishing a nitrification and denitrification enrichment environment. During this test period, data showed that the ammonium in the water within the shell structure was always high. The initial nitrogen product of respiration was reduced nitrogen or ammonium. After 4 days of immersion, the internal environment became less oxygenated, resulting in the formation of unionized ammoniacal nitrogen (NH3-N), which is toxic to marine organisms within the device. In addition to producing NH3-N, nitrite (NO2) and other toxic reactive nitrogen molecules may also be produced within the medium filling range of the shell structure. As the outside of the shell gradually becomes more fouled, this effect seems to be enhanced. Further, the microbial biofilm formed in and on the surface of the shell device may contribute to the general nitrification and denitrification pathways.

[0327] Various test data confirm that nitrate + nitrite (N + N) in the water within the shell structure is higher in many cases when compared to open water. This result may be related to the nitrification of ammonia under aerobic conditions. In some embodiments, even if the dissolved oxygen in the bag is low, it may not be enough to inhibit nitrification, and the source of ammonium may come from respiration. In some embodiments, the dissolved oxygen may not be low enough to promote dissimilatory nitrate reduction to ammonium (DNRA) or nitrate / nitrite ammoniation; however, there may be an anoxic microenvironment in the bag that can promote DNRA (dissolved oxygen concentration in the water is less than 0.5mg / L). DNRA is the result of anaerobic respiration of microorganisms, using nitrate as an electron acceptor, first reduced to nitrite, and then reduced to ammonium.

[0328] In addition, during the salt water test, the total dissolved nitrogen (TDN) in the closed water area is generally higher than that in the open water area. This result is consistent with high microbial respiration and dissolved nitrogen decomposition from particles. In some embodiments, particle sedimentation in the low energy environment of the shell causes a source of sedimentation of dissolved nutrients to the closed water area. In some embodiments, this sedimentation, dead, dying or decomposed particles at the bottom of the shell can explain the water chemistry and water quality differences in the shell water and the open water. These decomposed particles or sediments may consume most of the dissolved oxygen in the shell structure.

[0329] CO is released during respiration 2 , which in turn can lower the pH to drive or reduce to carbonates. By creating an increase in carbonic acid in the seawater, the water causes more acidic conditions, which lowers the pH measure. Organisms respond quickly to a decrease in dissolved oxygen, especially when it starts to reach levels of 3mg / L or 2mg / L. This difference in the water can cause an organism to be unable to produce a shell or to produce a thinner shell. Additionally, if the oxygen difference is too great, this difference can cause an organism to be unable to settle or swim and / or move to a different location.

[0330] Carbonate chemistry also appears to have modified within the enclosure structure, with entrained water becoming more corrosive to the mineralization of calcium carbonate over time. To enable comparisons between open and enclosed waters sampled during the experiment, a single integrated measure, the Aragonite Saturation Index (Ω-Ω), can be produced for each water column sampled at a specific point in time using the NOAA CO2 Sys program that assesses changes in carbonate water chemistry. The Aragonite (Aragonite is the crystalline form of the mineral calcium carbonate) Saturation Index (Ω) is a dimensionless number that indicates the degree of supersaturation of calcium carbonate in seawater. Values ​​greater than 1 indicate supersaturation (aragonite will increase in size), and values ​​less than 1 indicate undersaturation (aragonite will dissolve). Chemical oceanographers rely on Ω values ​​to determine the magnitude and trend of ocean acidification for a given ocean water column. A decreasing Ω trend is viewed as a corrosive threat to calcium carbonate formation. The determination of Ω depends on the following parameters: salinity, water temperature, depth (as pressure), phosphate, silica, ammonium, alkalinity, and pH. Integrating all of these parameters into a single unified measure allows for direct comparisons between water column samples taken during settling experiments (e.g., Fig. 12B shown).

[0331] The Redfield ratio or Redfield stoichiometry was analyzed to understand the atomic ratios of carbon, nitrogen, and phosphate found in marine phytoplankton within the waters inside the enclosure structure and in the open water. Using this theory, nutrient limitation was studied at a ratio of carbon:nitrogen:phosphorus in seawater = 106:16:1. Based on the increased concentration levels of ammonium (i.e., nitrogen) and phosphate in the waters inside the enclosure, it was determined that in some embodiments, there may not be any nutrient limitation in the waters inside the enclosure compared to the open water.

[0332] In one embodiment, the shell can be used as a bottom for bacterial colonization and macro-scale fouling sedimentation. The free exchange of dissolved oxygen, ammonia, nitrite and nitrate can occur across a permeable shell. In one embodiment, the breathing of macro-scale and / or bacterial biofilm can explain most of the oxygen and / or chemical nutrient absorption across a permeable shell. When water passes through or exchanges into a permeable shell, the biofilm may consume oxygen, nitrogen, phosphate and other nutrients. The bacterial biofilm can begin to participate in the oxygen absorption rate (OUR) of the shell until the shell water area reaches a stable state relative to the biofilm OUR. In an example, relative to the biofilm, the stable state of nutrients in the water in the shell may occur in less than 12 months, less than 6 months, less than 3 months, 1 to 60 days, 1 to 30 days or at the 58th day. In many embodiments, the bacterial biofilm grown in the shell or on the shell surface and the invertebrate macro-scale growing on the outer surface of the shell may be responsible for establishing and maintaining a fixed film barrier, which can provide significant antifouling protection. In certain embodiments, the film barrier can be a mechanism to prevent biofouling from occurring in a water chamber closed by a fabric structure.

[0333] Typically, unionized ammonia (NH3-N) is highly toxic to both aquatic and marine species, at levels approaching 100 μg / L (ppb). After the 7th day, the NH3-N concentrations observed from within the device were approaching 20% ​​of the toxic level, and may be higher. Another potential cause of toxicity within the device is nitrite (NO2), which is considered toxic at levels of 1 ppm. During the saltwater experiments, the dissolved oxygen in the device did not drop to hypoxic levels (hypoxia occurs when dissolved O2 is below 2 mg / L), but it showed a downward trend. Because this water chemistry mechanism is not dependent on any specific microbial biofilm, it is also important for freshwater applications.

[0334] In another example, water chemistry and water quality freshwater samples were collected and analyzed from experiments at the University of Wisconsin (UWM) in Milwaukee. A shell structure was deployed to protect valves and boats from scaling in the Great Lakes. After 1 month of immersion, water samples were collected in the shell and open water...

Claims

1. An assembly for reducing biofouling on a surface at least partially immersed in an aqueous environment, the assembly comprising: at least one structure that is or becomes water permeable during use, wherein the structure comprises at least one of a mesh, grid, fenestrations or holes that allow fluid to flow therethrough, wherein the structure is flexible and defines a first side and an opposing second side, wherein the at least one structure allows fluid to be exchanged therethrough to the surface while preventing or limiting biofouling on the surface when the at least one structure at least partially surrounds the surface in the aqueous environment such that the first side of the structure faces the surface, such that a first chemistry of the aqueous environment between the surface and the first side of the structure is different from a second chemistry of the aqueous environment beyond the second side of the structure, wherein the first chemistry is measured in the aqueous environment proximate to the surface, wherein the second chemistry is measured in the aqueous environment at a separation distance from the second side of the structure facing away from the surface, The component is open to the aqueous environment around a portion of the surface so as to form one or more pathways in the aqueous environment around the structure leading to the surface.

2. The assembly of claim 1, wherein the portion of the assembly open to the aqueous environment corresponds to at least one of a bottom or a side of the assembly.

3. The assembly of claim 1, wherein the portion of the assembly that is open is a gap in the assembly.

4. A component according to claim 1, wherein the portion of the component open to the aqueous environment is free of the structure, so that fluid from the aqueous environment outside the second side of the structure can flow around the structure and through the portion of the component without having to pass through at least one of the mesh, grid, fenestration or hole of the structure.

5. The assembly of claim 1, wherein the structure comprises a biocide.

6. The assembly of claim 1, wherein the structure comprises a fabric.

7. An assembly according to claim 6, wherein the fabric is formed from a three-dimensional fabric or fiber matrix formed from interwoven or tangled strands formed in a grid, mesh or fenestrated arrangement.

8. The assembly of claim 1, wherein the structure comprises at least one of a film, a membrane, or a sheet.

9. The assembly of claim 1, wherein said structure provides an average water exchange of about 0.1% to 500% of the volume of water passing therethrough per hour when said structure at least partially surrounds said surface in said aqueous environment.

10. The assembly of claim 1, wherein the structure has a permeability in the range of about 0.06-46.71 milliliters of water per square centimeter per second when the structure at least partially surrounds the surface in the aqueous environment.

11. The assembly of claim 1 , wherein the structure has a permeability in the range of about 0.90-14.72 milliliters of water per square centimeter per second when the structure at least partially surrounds the surface in the aqueous environment.

12. The assembly of claim 1, wherein the structure has a permeability of about 100 milliliters of water per second per square centimeter or less when the structure at least partially surrounds the surface in the aqueous environment.

13. The assembly of claim 1, wherein the separation distance from the second side of the structure is 12 inches.

14. The assembly of claim 1, wherein the first water chemistry differs from the second water chemistry by having at least one difference in a water chemistry property, wherein the water chemistry property is one of dissolved oxygen, pH, total dissolved nitrogen, ammonium, nitrate, orthophosphate, total dissolved phosphate, silica, salinity, alkalinity, or chlorophyll.

15. The assembly of claim 14, wherein the at least one difference in the water chemistry is a difference of at least 10% as measured after the structure is at least partially submerged in the aqueous environment for at least 2 days.

16. The assembly of claim 1, further comprising a floatable device, wherein the structure is attached to the floatable device.

17. The assembly of claim 16, further comprising one or more attachment features, wherein the structure is connected by the one or more attachment features so as to extend downwardly into the aqueous environment below the floatable unit.

18. The assembly of claim 1, wherein the at least one structure comprises a first structure positioned at a first distance from the surface, and wherein the assembly further comprises a second structure positioned at a second distance from the surface, wherein at least a portion of the second structure is positioned between the surface and the first structure.

19. The assembly of claim 18, wherein the first structure and the second structure are relatively positioned relative to the surface to form a tortuous path to the surface.

20. The assembly of claim 1, wherein the at least one structure comprises a first structure and a second structure, wherein each of the first structure and the second structure are spaced apart from the surface, wherein the first structure and the second structure are arranged in an at least partially overlapping arrangement.

21. A component according to claim 20, wherein the first structure defines a top, a bottom, and at least one first edge between the top and the bottom, wherein the second structure defines a top, a bottom, and at least one first edge between the top and the bottom, and wherein at least a portion of the first edge of the first structure is attached to at least a portion of the first edge of the second structure.

22. The assembly of claim 20, wherein the first structure is not attached to the second structure along an edge such that at least a portion of the first structure is free to move relative to the second structure.

23. The assembly of claim 1, wherein the structure comprises a plurality of layers, wherein at least one layer of the plurality of layers is removable from a remaining set of the plurality of layers.

24. The component of claim 1, further comprising an aqueous flow mechanism comprising at least one inlet or outlet positioned between the structure and the surface, wherein the aqueous flow mechanism is configured to at least one of add liquid or other material to the aqueous environment or remove liquid or other material from the aqueous environment.

25. The assembly of claim 1, wherein the structure comprises a permeable fabric comprising one or more channels extending from an opening on the first side to an outlet on the second side, wherein the permeable fabric further comprises a coating substance extending at least partially along the one or more channels, wherein the coating substance is configured to alter the permeability of the fabric.

26. The assembly of claim 25, wherein the coating substance comprises a biocide.

27. The assembly of claim 25, wherein the coating substance comprises paint or a paint-like substance.

28. The assembly of claim 25, wherein the coating substance is applied to reduce variability in permeability of different ones of the one or more channels.

29. An apparatus for reducing biofouling on a substrate at least partially submerged in an aqueous environment, the apparatus comprising: a structure that is or becomes water permeable during use, wherein the structure comprises at least one of a mesh, a grid, openings or holes that allow fluid to flow therethrough, wherein when the structure at least partially surrounds the substrate in the aqueous environment, the structure divides the aqueous environment into a localized aqueous environment and an open aqueous environment relative to the substrate and provides fluid flow therethrough while reducing biofouling in the localized aqueous environment relative to the open aqueous environment; and At least one opening, the at least one opening forming one or more pathways in the aqueous environment surrounding the structure to the substrate, so that fluid from the open aqueous environment can flow around the structure, through the at least one opening, and into the local aqueous environment without having to pass through at least one of the mesh, grid, fenestration or hole of the structure.

30. The device of claim 29, wherein the at least one opening corresponds to at least one of at least a portion of a bottom or at least a portion of a side of the device.

31. The apparatus of claim 29, wherein the structure is configured to extend downwardly into the aqueous environment from top to bottom.

32. The device of claim 29, wherein the structure provides an average water exchange of about 0.1% to 500% of the volume of water passing therethrough per hour when the structure at least partially surrounds the substrate in the aqueous environment.

33. The device of claim 29, wherein the structure has a permeability in the range of about 0.06-46.71 milliliters of water per square centimeter per second when the structure at least partially surrounds the substrate in the aqueous environment.

34. The device of claim 29, further comprising a floatable device, wherein the structure is attached to the floatable device.

35. The device of claim 34, further comprising one or more attachment features, wherein the structure is connected by the one or more attachment features so as to extend downwardly into the aqueous environment below the floatable device.

36. The device of claim 29, wherein the structure comprises a permeable fabric comprising one or more channels extending from an opening on the first side to an outlet on the second side, wherein the permeable fabric further comprises a coating substance extending at least partially along the one or more channels, wherein the coating substance is configured to alter the permeability of the fabric.

37. The device of claim 36, wherein the coating material comprises a biocide.

38. The device of claim 36, wherein the coating substance comprises paint or a paint-like substance.

39. The device of claim 36, wherein the coating substance is applied to reduce variability in permeability of different ones of the one or more channels.

40. A system for reducing biofouling on a surface at least partially submerged in an aqueous environment, the system comprising: at least one structure that is or becomes water permeable during use, wherein the structure comprises at least one of a mesh, a grid, fenestrations or holes that allow fluid to flow therethrough, wherein the structure is flexible and defines a first side and a second side, wherein the structure allows fluid to be exchanged therethrough to the surface while preventing or limiting biofouling on the surface when the structure at least partially surrounds the surface in the aqueous environment such that the first side of the structure faces the surface, such that a first chemistry of the aqueous environment between the surface and the first side of the structure is different from a second chemistry of the aqueous environment beyond the second side of the structure, wherein the first chemistry is measured in the aqueous environment proximate to the surface, wherein the second chemistry is measured in the aqueous environment at a separation distance from the second side of the structure facing away from the surface, At least one opening, the at least one opening forming one or more pathways in the aqueous environment surrounding the structure to the surface, allowing fluid to flow around the structure without having to pass through at least one of the mesh, grid, fenestration or aperture of the structure.

41. The system of claim 40, wherein the at least one opening corresponds to at least one of at least a portion of a bottom or at least a portion of a side of the system.

42. The system of claim 40, further comprising at least one floatable device attached to the structure, wherein the at least one floatable device is configured to float on a top surface of the aqueous environment to enable the structure to maintain a certain depth within the aqueous environment.

43. The system of claim 40, further comprising one or more attachment features, wherein the structure is connected by the one or more attachment features so as to extend at least downwardly into the aqueous environment below one or more flotation tubes or floats.

44. The system of claim 40, wherein the structure comprises a plurality of layers, wherein at least one layer of the plurality of layers is removable from a remaining set of the plurality of layers.

45. The system of claim 40, further comprising an aqueous flow mechanism comprising an inlet or outlet positioned between the structure and the surface, wherein the aqueous flow mechanism is configured to at least one of add liquid or other material to the aqueous environment or remove liquid or other material from the aqueous environment.

46. ​​The system of claim 40, further comprising a modifying compound positioned within the aqueous environment between the structure and the surface, wherein the modifying compound is configured to condition the aqueous environment by applying a change in water chemistry of the aqueous environment.

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