Dredge component based aggregate and method of making an aggregate

Abstract

A method of making aggregate from dredge compounds, which includes employing a significant amount of such mining tailings in combination with a calciferous additive, sodium hydroxide, and water to cure the shape the same under the influence of controlled pressure and temperature for a predetermined time to create aggregate which is characterized by a mineralogical crystalline phase. The dredge includes a mixture of fine particulate material and coarser particulate material.

Description

PATENT ATTORNEY DOCKET ECH-005 DREDGE COMPONENT BASED AGGREGATE AND METHOD OF MAKING AN AGGREGATE CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] None. FIELD OF THE DISCLOSURE

[0002] Aspects of the disclosure relate to producing an aggregate material from dredge materials. The aggregate material produced may be used in construction as a back-fill material or as a component in concrete. More specifically, aspects of the disclosure relate to producing a dredge material (dredge spoils) based aggregate as well as a method of making the aggregate to be used in the construction industry. BACKGROUND

[0003] The construction industry is a major contributor to greenhouse gas emissions. Regulatory adjustments, over time, have increased scrutiny over methods and products that contribute to such greenhouse gas emissions. As society grows, new buildings, highways, and structures are built in order to accommodate new societal needs. While the needs are ever increasing; unfortunately, the amount of raw materials that are conventionally used for production of the products necessary for creation are limited. These limitations cause costs of building to escalate due to supply and demand issues. Generally, conventional building materials have been produced for centuries and it is extremely rare when a new construction material becomes available for use on the open market.

[0004] Transportation inside the United States and across the world takes many forms. Transportation by water predates many other types of travel including air travel, the automobile, and rail. While water transportation has been understood for centuries, problems continue to exist for this type of transportation. Natural processes often have deleterious effects on water transportation. Lakes, rivers, and bays are constantly being subjected to many forces that move materials around. These materials, such as rock and 1 INFORMATIONPATENT ATTORNEY DOCKET ECH-005 DREDGE COMPONENT BASED AGGREGATE AND METHOD OF MAKING AN AGGREGATE sand, become significant barriers to passing ships and present a hazard for water transportation. Conventional remedial actions are taken to remove the hazards to shipping by dredging selected portions of the water body to enable the ship to traverse the water body. These remedial measures are undertaken in areas that are subjected to high traffic volumes in water. Unfortunately, the materials that are removed from the waterways also contain contaminants from pollution and other sources. These pollutants can include entrained hydrocarbons, mercury, arsenic, and other heavy metals. Conventional processing of the dredge materials is to merely store the materials in a designated area. In some instances, the designated area is a non-heavily traveled portion of the waterway.

[0005] When the dredge materials are dumped back into the waterway, heavy metal contaminants may then reenter the waterway and cause harm to the environment. In some instances, the pollution from the dredge materials is transported over a large area, thereby causing a greater amount of environmental damage than the original contamination.

[0006] Alternative strategies exist for conventionally handling the dredge materials. In these strategies, a land-borne sequestration area is developed and the dredge materials are deposited within the area. To control run-off, earthen berms made of virgin material are positioned at the perimeter of the sequestration area and act to filter any run-off water and materials from further contaminating the environment.

[0007] While sequestration areas provide somewhat effective containment of toxins, large areas of potentially useful land are required to house the dredge materials. Maintenance must be maintained for the sequestration area, thereby increasing costs and complexity of operations. The dredge materials themselves are not used for any beneficial purpose. 2 INFORMATIONPATENT ATTORNEY DOCKET ECH-005 DREDGE COMPONENT BASED AGGREGATE AND METHOD OF MAKING AN AGGREGATE

[0008] There is a need to provide a beneficial use of dredge materials. The beneficial use of the dredge materials should reduce greenhouse gas emissions. The beneficial use should also eliminate the toxicity of the dredge materials so that the materials may be used in a wide range of materials.

[0011] There is a need to provide an apparatus and methods to enable the production of structural materials incorporating these dredge materials. The production of the structural materials should be done to prevent costly sequestration and handling costs of the dredge materials.

[0012] There is a further need to provide apparatus and methods that do not have the drawbacks of leakage of toxic materials such as heavy metals, lead, mercury, arsenic, and poly chlorinated biphenals (PCB’s) over time.

[0013] There is still further need to reduce economic costs associated with operations and apparatus described above with structural material fabrication.

[0014] There is a further need to provide a beneficial use that meets the more complex regulatory requirements placed upon such materials from such regulations. SUMMARY

[0015] So that the manner in which the above recited features of the present disclosure can be understood in detail, a more particular description of the disclosure, briefly summarized below, may be had by reference to embodiments, some of which are illustrated in the drawings. It is to be noted that the drawings illustrate only typical embodiments of this disclosure and are; therefore, not to be considered limiting of its 3 INFORMATIONPATENT ATTORNEY DOCKET ECH-005 DREDGE COMPONENT BASED AGGREGATE AND METHOD OF MAKING AN AGGREGATE scope, for the disclosure may admit to other equally effective embodiments without specific recitation. Accordingly, the following summary provides just a few aspects of the description and should not be used to limit the described embodiments to a single concept.

[0016] In one example embodiment, a method to produce a dredge material based aggregate is disclosed. The method comprises receiving a feedstock of dredge materials. The method further comprises separating the feedstock of materials into a size of less than 35 microns, to create a separated fraction of sized dredge based components. The method further comprises combining a weighed portion of at least one of a lye and a lime amount to a measured portion of the separated fraction of sized dredge based components to create a mixture, wherein a mix ratio of 3 percent to 15 percent of one of calcium oxide and calcium hydroxide and 1 percent to 5 percent sodium hydroxide based on weight is achieved. The method further comprises dry mixing the mixture to create a mixed dry mixture. The method further comprises adding water to the mixed dry mixture to create a green mixture. The method further comprises hydraulically roller pressing the green mixture into a mold to directly form a green aggregate. The method further comprises thermally curing the green aggregate in an autoclave to form the dredge component based aggregate.

[0017] In another example embodiment, a method to produce a dredge component based aggregate is disclosed. The method may comprise receiving a feedstock of dredge component materials. The method may further comprise separating the feedstock of dredge component materials into a size of 35 microns or less to create a separated fraction of dredge component materials. The method may further comprise combining a weighed portion of at least one of a calcium oxide, calcium hydroxide, and sodium hydroxide to a weighed portion of the separated fraction of dredge component materials to create a mixture, wherein a mix ratio of 3 percent to 15 percent of one of calcium oxide 4 INFORMATIONPATENT ATTORNEY DOCKET ECH-005 DREDGE COMPONENT BASED AGGREGATE AND METHOD OF MAKING AN AGGREGATE and calcium hydroxide and 1 to 5 percent sodium hydroxide based on weight. The method may further comprise dry mixing the mixture. The method may further comprise mixing the mixture with water to create a green mixture. The method may further comprise roller pressing the green mixture into a pre-shaped mold to directly form a formed shape. The method may further comprise thermally curing the formed shape in an autoclave at a temperature between 180 degrees Celsius and 225 degrees Celsius and a pressure of 140 pounds per square inch and 350 pounds per square inch and where heavy metals are driven off from the green mixture. The method may further comprise crushing the formed shape to an aggregate size material after the thermal curing.

[0018] In another example embodiment of the disclosure, a construction material based upon dredge materials is disclosed. The material includes a molded formed aggregate with a homogenous matrix of calcium silicate hydrates and sodium alumino-silicates with a stable crystalline structure formed into an aggregate shape. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] So that the manner in which the above recited features of the present disclosure can be understood in detail, a more particular description of the disclosure, briefly summarized above, may be had by reference to embodiments, some of which are illustrated in the drawings. It is to be noted; however, that the appended drawings illustrate only typical embodiments of this disclosure and are therefore not be considered limiting of its scope, for the disclosure may admit to other equally effective embodiments.

[0020] FIG. 1 is a systemized approach for producing a dredge material based aggregate and method of making an aggregate.

[0021] FIG. 2 is a method for producing an aggregate from dredge materials in conformance with the systemized approach of FIG.1. 5 INFORMATIONPATENT ATTORNEY DOCKET ECH-005 DREDGE COMPONENT BASED AGGREGATE AND METHOD OF MAKING AN AGGREGATE

[0022] To facilitate understanding, identical reference numerals have been used, where possible, to designate identical elements that are common to the figures (“FIGS”). It is contemplated that elements disclosed in one embodiment may be beneficially utilized on other embodiments without specific recitation. DETAILED DESCRIPTION

[0023] In the following, reference is made to embodiments of the disclosure. It should be understood; however, that the disclosure is not limited to specific described embodiments. Instead, any combination of the following features and elements, whether related to different embodiments or not, is contemplated to implement and practice the disclosure. Furthermore, although embodiments of the disclosure may achieve advantages over other possible solutions and / or over the prior art, whether or not a particular advantage is achieved by a given embodiment is not limiting of the disclosure. Thus, the following aspects, features, embodiments, and advantages are merely illustrative and are not considered elements or limitations of the claims except where explicitly recited in a claim. Likewise, reference to “the disclosure” shall not be construed as a generalization of inventive subject matter disclosed herein and should not be considered to be an element or limitation of the claims except where explicitly recited in a claim.

[0024] Although the terms first, second, third, etc., may be used herein to describe various elements, components, regions, layers, and / or sections, these elements, components, regions, layers, and / or sections should not be limited by these terms. These terms may be only used to distinguish one element, components, region, layer or section from another region, layer, or section. Terms such as “first”, “second” and other numerical terms, when used herein, do not imply a sequence or order unless clearly indicated by the context. Thus, a first element, component, region, layer, or section discussed herein 6 INFORMATIONPATENT ATTORNEY DOCKET ECH-005 DREDGE COMPONENT BASED AGGREGATE AND METHOD OF MAKING AN AGGREGATE could be termed a second element, component, region, layer, or section without departing from the teachings of the example embodiments.

[0025] When an element or layer is referred to as being “on,” “engaged to,” “connected to,” or “coupled to” another element or layer, it may be directly on, engaged, connected, or coupled to the other element or layer, or interleaving elements or layers may be present. In contrast, when an element is referred to as being “directly on,” “directly engaged to,” “directly connected to,” or “directly coupled to” another element or layer, there may be no interleaving elements or layers present. Other words used to describe the relationship between elements should be interpreted in a like fashion. As used herein, the term “and / or” includes any and all combinations of one or more of the associated listed terms.

[0026] Some embodiments will now be described with reference to the figures. Like elements in the various figures will be referenced with like numbers for consistency. In the following description, numerous details are set forth to provide an understanding of various embodiments and / or features. It will be understood; however, by those skilled in the art, that some embodiments may be practiced without many of these details, and that numerous variations or modifications from the described embodiments are possible. As used herein, the terms “above” and “below”, “up” and “down”, “upper” and “lower”, “upwardly” and “downwardly”, and other like terms indicating relative positions above or below a given point are used in this description to more clearly describe certain embodiments.

[0027] Aspects of the disclosure provide for a method for producing an aggregate that may be used in the construction industry. Embodiments of the method produce an aggregate with a significant amount of dredge materials in combination with other materials. These other materials may include calciferous additives, sodium hydroxide, 7 INFORMATIONPATENT ATTORNEY DOCKET ECH-005 DREDGE COMPONENT BASED AGGREGATE AND METHOD OF MAKING AN AGGREGATE and water. The materials may be mixed together and placed in a form. The material within the form may be cured under the influence of controlled pressure and temperature for a predetermined time to create an aggregate which is characterized by a mineralogical crystalline phase.

[0028] Embodiments of the disclosure provide for an aggregate that may be used widely in the construction industry. Toxic elements, such as heavy metals, are encapsulated in the aggregate or are driven off based upon the processing of the aggregate. In embodiments, the aggregate may be heat treated within an autoclave. Heated under a specified temperature and pressure, heavy metals may be driven off of the dredge materials and captured for beneficial use. The heavy metals may be, in some instances, beneficially used in other industrial manufacturing, such as in the chemical industry. In embodiments, the heavy metals may be arsenic, lead, mercury, and cadmium as non- limiting embodiments. The resulting aggregate exiting the autoclave may be directly used in industry or may be resized to fulfill an engineering specification for porosity, angularity, and size. Resulting aggregate from the methods disclosed have been tested through an exhaustive number of established testing methods to determine the properties of the aggregate.

[0029] As construction materials are exposed to weathering conditions, such materials must be weather resistant. The resistance that is desired takes several forms. In extreme Northern and Southern climates, significant freeze / thaw cycles may be encountered by the construction materials. Other types of weathering conditions include exposure to water environments. In embodiments, the construction material may incorporate water and, when a freeze / thaw cycle is experienced, the entrained water may expand upon freezing and contract upon thawing. When aggregate is incorporated into other materials, this freezing and thawing may cause localized stresses to be experienced. Replication of the freeze / thaw cycles is important in understanding the capability of the material being 8 INFORMATIONPATENT ATTORNEY DOCKET ECH-005 DREDGE COMPONENT BASED AGGREGATE AND METHOD OF MAKING AN AGGREGATE used. In testing, a 50 cycle thaw process is performed in conformance with AASHTO (American Association of State Highway and Transportation Officials) T 103 test methods. The test simulates the amount of weathering that an aggregate would undergo in field conditions. In the embodiments described, the resulting aggregate produced by the methods described provide acceptable results.

[0031] Dredge materials, due to their location next to industrial facilities, may have significant amounts of hydrocarbons entrained within the material. The amount of hydrocarbon material may be minimal, or a significant percentage of the dredge materials may include carbon materials. In accordance with this, it is desired to test the amount of carbon within the dredge materials. The final aggregate produced by the process was tested for a loss of ignition according to standard ASTM C 25. In the test, a weight of a sample is obtained prior to further testing procedures. The sample is then subjected to a testing temperature that would be sufficient to ignite or drive off hydrocarbons from the sample. After heating the sample for a defined time, then aggregate sample is then weighed a second time and a difference in weight is recorded. As provided in Table 1, the loss of ignition (LOI) is minimal.

[0032] The aggregate produced by the method is desired to be used in different capacities that include a variety of environmental conditions. As non-limiting embodiments, the aggregate may be used as substrate supporting structures. These structures may include, for example, highway graded bed material. Other possible embodiments would include using the material as a graded material for large construction or landscaping activities.

[0033] Other possibilities exist for use of the aggregate. The aggregate may be used in under-water placement for slope stabilization. Still further embodiments allow for the aggregate to be used in other instances. These instances may include incorporation of 9 INFORMATIONPATENT ATTORNEY DOCKET ECH-005 DREDGE COMPONENT BASED AGGREGATE AND METHOD OF MAKING AN AGGREGATE the within concrete bodies to produce a concrete building structure, such as a block or a brick. In such uses, the aggregate may chemically react in the matrix of the block or brick. In still further embodiments, the aggregate may be used in more flowable concrete mixtures that are sprayed into place such as gunnite.

[0034] As the aggregate may experience different types of environments, a test under ASTM C 88 was conducted. ASTM C 88 requires repeated immersion of the aggregate in saturated solutions of sodium or magnesium sulfate. After immersion, the aggregate is oven dried. This oven drying dehydrates the salt precipitated in permeable pore spaces. The internal expansive force, derived from the rehydration of the salt upon a re- immersion, simulates the expansion of water upon freezing. The test provides information helpful in determining the soundness of aggregates when adequate information is not available from service records of the material exposed to actual weathering conditions. The results indicate sufficient soundness of the aggregate.

[0035] As discussed above, aggregate used in the construction industry may be exposed to mechanical forces. These mechanical forces may include compression, sheer as well as combinations of compressive and tensile forces. One significant force that may be placed upon an aggregate is the shear forces from abrasion. To evaluate the final products of the method and their ability to withstand abrasive forces, an abrasion test was conducted in conformance with ASTM C 131, where abrasive forces are placed upon the aggregate. The forces are created using a standard Los Angeles testing machine. ASTM C 131 specifies that a load of aggregate of approximately five pounds in weight is inserted into a drum. The drum is rotatable. Steel balls of various sizes are also placed within the rotatable drum. The mixture of steel balls and aggregate are raised through rotation of the drum or the materials are scooped up by mechanical arms to the top of the drum and allowed to drop. The materials fall to the bottom of the drum, thereby creating an overall crushing force on the aggregate. This action is repeated a 10 INFORMATIONPATENT ATTORNEY DOCKET ECH-005 DREDGE COMPONENT BASED AGGREGATE AND METHOD OF MAKING AN AGGREGATE standardized number of times and the aggregate is removed from the drum and weighed a second time. The amount of abrasion loss is then recorded. The resulting range for the tested aggregate shows little to no abrasion loss, thereby passing the test.

[0036] As the aggregate may be used in a variety of engineered locations and for many different purposes, it is desired to know the approximate gradation of the sizes of particles. For example, when incorporated into concrete, finer material should generally be removed and larger aggregate used to increase compressive strength. To ascertain the amount of light weight particles in the aggregate, a sample of the aggregate was submersed in a high gravity liquid ASTM C 123 was used for characterization of the material. As specified by ASTM C 123, a high gravity liquid has a specific gravity over 2.0. Through this test, the amount of floating aggregate is determined. This may be used to determine the amount of coal or lignite remaining in the sample. As tested, the aggregate has little to no coal or lignite remaining in the material.

[0037] Petrographic analysis may be used to determine if materials to be mixed together are chemically unsuitable. To prevent an inadvertent mixing of aggregate with various known materials, a test under ASTM C 295 was conducted. The petrographic examination establishes whether the aggregate contains chemically unstable minerals, such as soluble sulfates or unstable sulfides that may form sulfuric acid. Other evaluations are also performed to analyze any potential distress that may be caused when the aggregate is combined with other materials. Such mixing may occur, for example, in concrete. Variations of the testing procedure were also conducted. In such variations, temperatures were increased to determine the viability in different temperature regimes. Unstable materials, such as smectites, are also determined as well as the presence of swelling clay materials. The results of such petrographic examinations shows acceptable results. 11 INFORMATIONPATENT ATTORNEY DOCKET ECH-005 DREDGE COMPONENT BASED AGGREGATE AND METHOD OF MAKING AN AGGREGATE

[0038] A test under ASTM C 142 was also performed. ASTM C 142 determines the amount of swellable clays and friable particles. These particles may be detrimental when the aggregate is incorporated into a concrete brick or block. Clays and friable materials at or near the surface of a structural element may result in pitting of the surface through wear. When bricks or blocks are made for architectural purposes, such defects may be unsuitable. Test results of the materials indicate a low percentage of clays and friable materials.

[0039] Other tests for identifying physical properties of the aggregate were also performed. These include determining bulk dry specific gravity, apparent specific gravity, and water absorption percentage. All tests recorded acceptable results. As will be further understood, sizing and grading of the actual final material may be accomplished through various mechanical means; therefore, the final product may be graded, as needed, per engineering specifications. Test Parameter Test Method Result Range 50 c cle free thaw % AASHTO T 103 0 – 5012 INFORMATIONPATENT ATTORNEY DOCKET ECH-005 DREDGE COMPONENT BASED AGGREGATE AND METHOD OF MAKING AN AGGREGATE

[0040] Referring to FIG.1, a process for making a dredge component based aggregate is illustrated. The method 100 entails receiving a shipment of dredge materials. The dredge materials may be obtained through digging in a waterway with a clamshell bucket attached to a crane. Other methods of extraction of dredge materials may be through suction of material through suction hoses placed upon a barge. A mechanical mover, such as a pump, may create a difference in pressure, thus removing the material from the waterway. Still further embodiments may include obtaining dredge materials from pre- embanked locations of past dredging activities. Thus, obtaining the dredge materials may allow for environmental clean-up of previously unusable land that was occupied by dredge materials. In some embodiments, the dredge materials may be of a dry consistency. If the dredge materials are wet when received, they may be pre-dried at the processing facility. The materials may be preprocessed to mix the materials to make a more homogenous mixture for processing. In other embodiments, the materials may already be graded, alleviating the need for preprocessing.

[0041] The transport of the materials may be through rail car or truck in some embodiments. In other embodiments, the apparatus creating the dredge material based aggregate is a mobile unit that is transported to the dredge material retention site or storage area. In further embodiments, the processing may occur near the dredging activity at waterside, to limit the amount of energy expended on transportation of materials. When located in such a location, the processing is more overall energy efficient. Such on-site locations are further helpful in reducing the amount of greenhouse gasses emitted by the entire process.

[0042] As will be understood, providing a mobile unit that processes the materials provides advantages over conventional treatment methods. For example, trucking or 13 INFORMATIONPATENT ATTORNEY DOCKET ECH-005 DREDGE COMPONENT BASED AGGREGATE AND METHOD OF MAKING AN AGGREGATE transportation of materials over roads, rails, or ship is minimized. Permitting for transporting what may be hazardous waste is also eliminated. Other advantages include eliminating “double handling” of materials, where the hazardous materials are merely placed into the treating apparatus, rather than handled, transported, unloaded, and then treated. Such elimination of double handling is not possible with conventional treatment processes.

[0043] After the receiving of the materials at step 102, the method progresses to step 104 and 106 as well as step 108. In step 104 materials that are generally lightweight and small in diameter size are separated out from other larger materials. The lightweight material at 104 is placed into storage. The storage location, due to the small and lightweight nature of the material, may be a silo to prevent the material from escaping with wind or rain. Materials that are larger in diameter than the lightweight material are processed in step 112. The material at 106 because it is larger in diameter size then the lightweight components at 104 are screened at step 112. If the material is considered to be acceptable in size, it is placed in the silo at 110 along with the lightweight material from step 104. If the material is too large at step 112, the material is then sent to a grinder or crusher at 114 and then passed through the screening test again at step 112. If the material is acceptable in size, it is then stored at 110 in the silos. If again the material is too large for the screens at 112 the material may be sent again to a grinder or crusher at 114 and then reprocessed through to the screening step at 112. In embodiments, the maximum size of material that would be allowed in the process is 35 microns. As will be understood, other thresholds may be applied if larger sized particles are to be processed.

[0044] As will be further understood, materials do not have to be added to the same silo at 110. Each of the materials may be stored in their own respective silo. Processing of materials to make the dredge component-based aggregate may include lightweight materials only, medium sized materials or larger sized materials. All of these materials 14 INFORMATIONPATENT ATTORNEY DOCKET ECH-005 DREDGE COMPONENT BASED AGGREGATE AND METHOD OF MAKING AN AGGREGATE may be mixed and used in combination or may be used exclusively in production of the aggregate.

[0045] Storage of the material constituents of the aggregate to be made may be made in a silo or other segregation method. Such methods may include bin storage and on site open-pit storage. In some embodiments, a batch process may be used such that long term material storage is eliminated and material is used by the process directly as it is received.

[0046] At 108, lye material as well as lime material at 116 may be stored in separate storage areas and then metered to a specific amount of lye and / or lime and added to the contents of the silo at 118. As will be understood, materials may be metered from the silo at 110 to a separate vat or container such that specific amounts of lye and / or lime may be added to the contents coming from the silo at 110. The resulting mixture is then weighed at 118.

[0047] Final products achieved may be obtained by following different types of batch formulas. For example, some aggregate types may use a greater amount of lye. Other types of aggregate may use relatively greater amounts of lime. Still further embodiments may use different types of lime and / or lye in the process. Each of the sub-components; therefore, may be weighed prior to addition to a mixing vat or dry mixer. In embodiments, the dry materials may be first dry mixed to achieve a relatively uniform mixture of materials based upon a dry batch formula. In some embodiments, a batch mixing process is performed where large amounts of each constituent are added to a hopper of a large rotary mixer. Rotary motion of the mixer then mixes the constituents together. Other forms of mixing, such as convective mixing, may also be performed. In such convective mixing processes, a base material travels along a beltway or other transportation mechanism and other constituents are added to the base material, thereby arriving at the 15 INFORMATIONPATENT ATTORNEY DOCKET ECH-005 DREDGE COMPONENT BASED AGGREGATE AND METHOD OF MAKING AN AGGREGATE end of the process with a mixed material. Still further types of mixing may be used such as paddle mixers, industrial ribbon mixers, double cone blenders, drum blenders, or shear mixers.

[0048] After the mixing of the dry components, water is added. Potable or non-potable water may be used. As illustrated, the materials are then mixed at 122 after water is added at step 120. The resultant material is defined as a “green” material or wet mix. The wet mix of material is then put into a mold where the green mixture is pressed at step 124. As will be understood, a hydraulic press may be used at step 124. Additionally, increasing the amount of efficiency of the process, a roller press may be used at step 124; therefore, providing a continuous processing ability for the method. The green mixture may be pressed to a specified value, such as processing through a 5000 pounds per square inch roller press. The use of a roller press is considered a valuable alternative to other presses as the amount of energy used by the roller press may be substantially less than other conventional hydraulic presses. The use of the roller press; therefore, is significant as the overall amount of energy usage and emissions that occur during the process are reviewed and rated by governmental agencies, such as the EPA. In one non-limiting embodiment, a single roller cylinder may be used as the green material is captive in a tray or mold. Other possibilities for a roller press include a dual action or dual roller system with top and bottom rollers. This may be applicable for final materials that are thinner as the top and bottom rollers compress the green mixture. In embodiments, the wet mix may be allowed to set or rest prior to compression. This setting or resting allows the water to chemically react with the lime and / or lye in the mixture. Such setting or resting may eliminate overstressing the final material where water is not fully combined in the green mixture. Resting times may vary depending upon the mixture. An example resting time may include a 5 minute resting time prior to using a roller press. 16 INFORMATIONPATENT ATTORNEY DOCKET ECH-005 DREDGE COMPONENT BASED AGGREGATE AND METHOD OF MAKING AN AGGREGATE

[0049] While the material constituents of the green mixture are designated by the batch design, the use of a dual action or dual roller system may allow for additional grinding of materials, if such a need arises. The use of a dual roller system; therefore, is not present in conventional systems. As the current methods described use more rugged materials, additional processing steps, such as a roller press, provide significant advantages over conventional systems. In the instance of a roller press, the amount of compressive force may be between 7000kN to 35,000kN.

[0050] Thicknesses of the green mixture, after compression, may vary. In some embodiments, the green mixture (prior to insertion into an autoclave for drying) may be 3 inches. Other values may be used. In some instances, thicknesses may be substantially decreased, thereby creating relatively thin strips of material. These strips may be easily converted through additional processing steps to make large or small aggregate. In one non-limiting embodiment, the green mixture may be placed into large sheets approximately 1 inch thick. Such thin sheets of green mix allow for accelerated drying times compared to thicker units, such as bricks. The thin sheets; therefore, may be more energy efficient in overall production than larger more conventional bricks. Smaller units with reduced sizes, such as bricketts may be created.

[0051] The green mixture, after being pressed at 124 is then sent to an autoclave at step 130. Materials are placed in the autoclave for a specific amount of time and cured. In the autoclave a humid atmosphere may be achieved by water at 126 being added to a boiler at 128 providing a steam atmosphere for the autoclave 130.

[0052] In some applications, the cured product from the autoclave may then be sent to a crusher to crush the material to a desired final size or grading. The crushing may result in a desired size of aggregate. The material may also be tumbled, as necessary, in a 17 INFORMATIONPATENT ATTORNEY DOCKET ECH-005 DREDGE COMPONENT BASED AGGREGATE AND METHOD OF MAKING AN AGGREGATE tumbling machine if the final product to be achieved specifies a non-angular resultant product.

[0053] After completion of curing in an autoclave, samples of the material may be tested at 132 to see if they conform to expected standards. As will be understood, the testing may be related to any or all of the tests identified in Table 1. Additional tests may also be performed, such as for size, specific gravity, angularity, or other features. If the testing, at 132 is acceptable, then packaging may be accomplished at 134. To this end, packaging may take many forms. The materials may be ordered in small batches or larger batches by a customer. Smaller batches may be placed in 20 pound to 50 pound bags for direct delivery to a consumer or to a retailer. Larger batches may be separated according to size of the material. Material may be stored in large freestanding piles that may be loaded onto railcars, trucks, ships, or other transportation devices. A unique feature of the method illustrated in FIG.1, is that if testing is not acceptable the method may return to step 114 for further grinding and crushing of the material. In these embodiments, the material that fails the testing is related to the size component of the aggregate that has been produced. To alleviate this concern, the overall size of the aggregate may be reduced. To achieve the size of the material as specified by the customer or project engineer, the size of the aggregate may be altered by an additional grinding or crushing at 114. In embodiments, the material that has been resized through mechanical forces was also tested for compliance with the various standards listed in Table 1. The action of grinding or crushing did not negatively impact the test results obtained.

[0054] Lime addition at 116 involves the addition of an inorganic material composed primarily of a calcium oxide and hydroxides. The type of hydroxides that may be incorporated with the calcium oxide may vary. In one non-limiting embodiment, calcium hydroxide is used. 18 INFORMATIONPATENT ATTORNEY DOCKET ECH-005 DREDGE COMPONENT BASED AGGREGATE AND METHOD OF MAKING AN AGGREGATE

[0055] The feedstock for the lime used at 116 may be obtained from various sources. In non-limiting embodiments, the source material may be from limestone that is extracted from quarries or mines.

[0056] Other alternatives exist in the process described. In some embodiments, quicklime may be used in place of calcium hydroxide. In this alternative process, quicklime is combined with water to produce calcium hydroxide. This process may be completed at the production site for ease of processing. Results obtained from standardized tests, described in Table 1, are similar for the produced aggregate, with all aggregate showing favorable results. Although the process at 116 shows a single step, the step may be subdivided by using quicklime with an addition of water to produce lime that is then weighed at 118 with material from the silos at 110.

[0057] Similar to using quicklime at 116, other type of lime may be used. As will be further understood there are different types of lime with other features that may be used for the lime function at 116. These limes include, but are not limited to, portlandite, brucite, magnesite, and other magnesium hydroxycarbonate compounds.

[0058] Lime may be characterized into three subcategories. Each of these subcategories may be used in combinations with the process. As will be understood, the three types of lime include pure, hydraulic, and poor lime. In embodiments of the methods described, hydraulic lime, also known as water lime, contains lime with a silica or alumina. Hydraulic lime reacts upon exposure to water. In embodiments, the amount of clay that is added to the hydraulic lime predicts the type of behavior of the hydraulic lime and ultimate use of the materials. With greater uses of clay materials, hydraulic lime can be used in more aggressive and freezing climates as compared to limes with lesser amounts of clay added. 19 INFORMATIONPATENT ATTORNEY DOCKET ECH-005 DREDGE COMPONENT BASED AGGREGATE AND METHOD OF MAKING AN AGGREGATE

[0059] Pure lime may also be used with the method. Pure lime may be used for a variety of conditions. Pure lime consists primarily of calcium hydroxide. Calcium hydroxide may be derived from quicklime with the addition of water. Other ingredients may be included on a weight basis of up to five percent. Pure lime may be used in areas where the material will ultimately be exposed to potential cracking. Such cracking may be experienced from environmental conditions, such as freeze and thaw conditions. Other cracking conditions may be due to repeated loads or cyclical loads.

[0060] The use of pure lime allows materials to leach out from the lime, such as calcium hydroxide, that fills void areas. Such void areas may be, for example, cracks that have developed within a structure. The leaching of the calcium hydroxide fills the void area, thereby filling the void and preventing a further repetition of a freeze thaw cycle, as water is prevented from penetrating further into the body of the structure. Due to the presence of this type of action, the structure is defined as a “self healing” structure.

[0061] Poor lime is characterized by comparatively longer set times and overall strength. To this end, poor lime may be used in low quality aggregates that do not need an extensive amount of encapsulation for toxic elements or materials and that also need a relatively cost-effective treatment process for production of the aggregate. As a result of the above, poor lime may be an attractive candidate for aggregate that is to be used as a road bedding material that is not exposed to freeze and thaw conditions and that does not have a requirement for high strength.

[0062] In the method 100, lye may be added at 108. In non-limiting embodiments, the addition of lye at 108 includes the addition of an alkali metal hydroxide. Different types of alkali metal hydroxides may be added. Example types of alkali metal hydroxides include sodium hydroxide or potassium hydroxide. 20 INFORMATIONPATENT ATTORNEY DOCKET ECH-005 DREDGE COMPONENT BASED AGGREGATE AND METHOD OF MAKING AN AGGREGATE

[0063] Different forms of lye may be added at 108. The type of lye that may be added in the process may be in the form of flakes, pellets, powders, solutions, or beads. One of the purposes of adding a lye to the matrix of the material being generated for aggregate production is to create an alkaline solution to prevent potential acidic attack upon the aggregate produced. In embodiments where the aggregate may experience a hostile environment that is acidic in nature, greater amounts of lye may be added to combat acid attack. One situation where this may happen includes the aggregate being used for grading at a chemical industrial facility. Other embodiments may include using the aggregate as part of a lining system for a waste disposal facility. In some instances, soils will have their pH change over the course of a year, ranging from neutral (approximately 7 pH) to acidic (defined at 5.5 pH or lower). This may happen due to drying of the soil during a calendar year. Types of soils that are rich in aluminum, alumina, and molybdenum are especially prone to being acidic. Such soils may be found, for example, in the southeastern United States, Northern portions of South America, Southeast Asia and extensive portions of Africa and Russia. In light of the possible environmental conditions in these locations, lye addition, conducted at 108, may be advantageous.

[0064] As will be understood, the amount of lye at 108 and the amount of lime at 116 may vary when added to the materials obtained from the silos at 110. In some instances, no lye is used. In some further instances, no lime is used at 116. Thus, the process may include various amounts of each component according to the type of aggregate that is needed for end production.

[0065] Referring to FIG.2, a method 200 in accordance with one example embodiment of the disclosure is illustrated. The method entails receiving materials at step 202. The receiving of the materials includes dredge materials obtained from a stockpile of such materials or the materials directly from the dredging project. A specification for the 21 INFORMATIONPATENT ATTORNEY DOCKET ECH-005 DREDGE COMPONENT BASED AGGREGATE AND METHOD OF MAKING AN AGGREGATE maximum size of aggregate may be submitted by a customer related to a specific project. In embodiments, a maximum size of dredge materials may be 35 microns. Other values may be used if larger aggregate is desired. For example, if the aggregate is to be used within a concrete matrix (such as a building block), then a 35 micron maximum size may be appropriate. As will be understood; however, aggregate of much greater size can be used within concrete, therefore the 35 micron size is but one possibility. The material is sized at 204 according to the maximum size range desired. If the material is not of the proper size at 204, the material may be resized at 222 through use of a grinding or abrasion method. In embodiments, the sizing may occur through a screening process. The screening process may use vertically oriented screens that trap larger size components from falling to the next (or subsequent) screen. The amount of material that cannot pass through the screen is therefore larger in diameter than the smallest size allowed through the screen.

[0066] In an alternative method step, a directly sized material may be directly used within the process. This would alleviate the need to perform screening, at 222, as described above. At 206, additives may be added to the size materials. The additives may be lime, lye, or other materials. The other materials may include architectural dyes or colorants that are specified for a desired color of the aggregate. Percentages and weights of different lime and lye may be incorporated into the size material arriving from 204. In embodiments, sand or other materials may be added to manufacture the green material, wherein green material is defined as the raw components in an unmixed and unwet state. The addition of sand or other materials may be controlled such that the overall specifications required for the material are maintained. To ensure the proper mixture, each of the individual components may be weighed at 208. The materials may then be dry mixed at 210. 22 INFORMATIONPATENT ATTORNEY DOCKET ECH-005 DREDGE COMPONENT BASED AGGREGATE AND METHOD OF MAKING AN AGGREGATE

[0067] After achieving a dry mix at 210, water may be added directly to the mixture obtained at 210 or the contents of the dry mixture may be emptied and placed into a wet mixer at 214. Water may be added at 212 to create the wet mixture at 214. The wet mixture generated at 214 is then provided to a roller press at 216. The roller press compresses the green mixture to a desired thickness. In embodiments, the green mixture is placed within a mold that is then fed to the roller press. A single or double roller press may be used.

[0068] Heating (curing) may occur at 218. Heat applied at 218 may be in a steam atmosphere in an autoclave. Other heating sources may be used other than an autoclave. In embodiments, the heating may be accompanied with a pressure exerted upon the green mixture. Pressure may vary according to the type of mix that is attempted.

[0069] In embodiments, a mobile autoclave is used such that the sized material from 204 is treated at dredge site or the dredge disposal area without need for shipping. After the heating process at 218, the size of the aggregate produced may be evaluated at 220. The size and operation performed at 220 may be through performance of dumping materials onto mechanical screens with separate fractions of material according to size. Such a size separation may be similar to other mechanical separation technologies previously described. Acceptable material results to an end of the process. Material that is not sized appropriately may be resized at 222. After the resizing at 222, if the material is acceptable, the process may end or additional additives may be provided. After resizing at 222 a query is run if the process has been previously completed at 224. If the process has been previously completed at 224 then the resized material may be used and the process ended. If the resized material has not been previously processed, the method may return back to 206 where additives of lime and lye are added. As will be understood, successive additions of lime and lye are prevented through the query run at 224. Thus, 23 INFORMATIONPATENT ATTORNEY DOCKET ECH-005 DREDGE COMPONENT BASED AGGREGATE AND METHOD OF MAKING AN AGGREGATE the batch process that is run to create the aggregate always maintains the correct chemical composition.

[0070] As will be understood, the roller press at 216 may be a dual roller press or a single roller press that impacts material into a predefined mold. In the process of making small aggregate, a dual roller press may be used to provide small or thin size aggregate as necessary. When a larger aggregate is needed, then a single sided roller press may be used at 216. In either embodiment, after heating of the green material at 218 an additional step of abrasive mechanical action, for example, may be accomplished to correctly size the heated material. As will be further understood, the roller press at 216 may directly determine the aggregate size from the rolling action in one step prior to heating. For example, such a roller press action may include mechanically separating components of area into desired sizes such as one-half inch aggregate maximum dimension size. The roller chosen, for example, may directly make materials in a variety of sizes such that a specific void ratio for the aggregate, placed in an amendment, is maintained below a specific threshold.

[0071] In instances where thin layers of aggregate are produced in the autoclave, the resulting material may be passed through another roller press for crushing the aggregate to a desired size. Such use of a roller press may also be accompanied by placing the aggregate into a drum mixer followed by rotation of the mixer. Such rotary tumbling may effectively break the aggregate down into desired sizes. The aggregate may then be mechanically screened down to specific aggregate sizes for use in desired projects.

[0072] In embodiments of the disclosure, 50 tons or more of aggregate can be processed per hour. Although described as using a roller press, other processes are possible, including an extrusion process where the green mixture is cut or shaped directly 24 INFORMATIONPATENT ATTORNEY DOCKET ECH-005 DREDGE COMPONENT BASED AGGREGATE AND METHOD OF MAKING AN AGGREGATE into desired sizes. When using an extrusion process, overall aggregate size used within the green mixture may be small to allow for extrusion capability.

[0073] In embodiments, separate steps of drying may occur. For example, if the feedstock of dredge material is wet, a separate step of drying may occur prior to other processing steps. Other steps of drying may occur. For example, the green material may be dried after the roller press or extrusion process occurs.

[0074] In embodiments, the drying process may include holding the aggregate in trays for periods up to and possibly exceeding 36 hours. This drying process would be in addition to the firing at the autoclave at 130. Firing time at the autoclave may be determined upon the size of the aggregate produced. Firing may take from one-half hour, in the case of small aggregate, to 10 hours, in the case of large size material. Autoclave temperatures of between 180 degrees Celsius and 250 degrees Celsius may be used as a non-limiting temperature profile. After autoclave thermal treatment, a separate step of cooling may also occur prior to packaging at 134 or determining size acceptance at 220. Cooling may be accomplished through open air rack cooling of the cured aggregate. In other embodiments, the cooling may be accomplished in a step process of holding the aggregate at specific temperatures for predetermined times. After exhaustion of the predetermined time, the temperature may be lowered, followed by another holding time at the second cooling temperature. Such regulation of temperature prevents thermal shock to the materials.

[0075] The autoclave used at 130 may be equipped to handle toxic element vaporization, thereby capturing vaporized hazardous emissions. Such emissions may include those of mercury, arsenic, or other heavy metals. As such, ordinary kiln technology, which does not provide this environmental benefit, is not used, as the fugitive emissions would be considered to be a generated waste, impacting the overall 25 INFORMATIONPATENT ATTORNEY DOCKET ECH-005 DREDGE COMPONENT BASED AGGREGATE AND METHOD OF MAKING AN AGGREGATE environmental clean-up capability of the process. In further embodiments, for small aggregate production, the autoclave times may be minimized; therefore, providing an economic benefit for greenhouse gas emissions from the process. Such controlled temperature, pressure, and environmental processing allows the present process to be used as a viable environmental clean-up technology compared to conventional processes which are banned from such activities by current United States Environmental Protection Agency regulations.

[0076] The use of the autoclave at 130 has further advantages compared to kiln type drying procedures. First, use of the autoclave at 130 provides a reduction in the total amount of greenhouse gases produced. In kiln drying, kilns must be preheated to achieve a desired temperature. The preheat technique requires heat soaking of the kiln masonry components that can take many hours or days. During that heat up time, the kiln produces greenhouse gases that are considered an emission by the EPA. Thus, use of a kiln may result in an overall production of greenhouse gases that would prove to be unsuitable for permitting under EPA regulations. No such concerns are present using an autoclave whereby heating and greenhouse gas emissions are reduced.

[0077] The autoclave used at 130 also has the advantage of keeping a controlled humidity and pressure inside the unit during the heating process. Pressures up to 16 atmospheres may be exerted on the aggregate during the heating process, thereby chemically combining the lime and / or lye with the dredge materials to encapsulate toxic elements. Humidity levels up to 100 percent relative humidity may be used to provide a structurally sound final product. Kiln firing does not provide such an advantage compared to use of an autoclave.

[0078] Additives may be added to the green material, in order to provide a desired architectural color. Additions of zinc and / or iron, as non-limiting possibilities, may be 26 INFORMATIONPATENT ATTORNEY DOCKET ECH-005 DREDGE COMPONENT BASED AGGREGATE AND METHOD OF MAKING AN AGGREGATE added to the green mixture to produce a required shade of material. Test samples of aggregate that incorporates additives shows no detrimental effects from incorporation of color additives.

[0079] The environmental process provided herein has several advantages over conventional aggregate production. Conventional aggregate production has at least three mechanical crushing steps that are undertaken to arrive at a finalized product. The mechanical crushing processes are, in order, a primary jaw crusher, a secondary cone crusher, and a tertiary cone crusher. Each of these mechanical crushing steps involves use of fuels, production of heat, and emissions that are not present in the present disclosure. For example, conventional aggregate is first mined at a geological deposit. The aggregate is then transported to a processing facility. This transportation involves the expenditure of energy and greenhouse gas emissions. Once at the processing location, the material is provided to a main primary jaw crusher. Generally, the step of using a primary jaw crusher is necessary because the overall size of the aggregate obtained from nature requires crushing of large portions. Contrary to conventional processes, this step is eliminated through the current process as the materials are generally smaller in size and do not require massive jaw crusher capabilities. The method described herein merely need to provide a mechanical screening capability that is vastly superior in energy usage.

[0080] Conventional technologies also use a secondary cone crusher to crush medium size pieces down to more manageable sizes. Again, the current process does not use the secondary cone crusher process, saving on fuel, energy, and environmental emissions. The currently described embodiments merely need to provide a mechanical screening. As will be understood, a crusher may be used in the present embodiments described; however, the use of such a crusher, in many cases, is eliminated. 27 INFORMATIONPATENT ATTORNEY DOCKET ECH-005 DREDGE COMPONENT BASED AGGREGATE AND METHOD OF MAKING AN AGGREGATE

[0081] Conventional aggregate production does not ensure the non-transmission of toxic materials. For example, many types of mines are located in geologically rich areas that can be mined for many purposes. These geologically rich areas can provide entrained heavy metals in the ores obtained. In conventional aggregate production, the material obtained from the geological stratum is not tested for heavy metals. In such cases, the ore incorporating the heavy metals may be used directly in construction sites, contaminating large areas. In embodiments of the described process, any heavy metals not chemically combined during the mixing process and setting process with the lime / lye are driven off by the autoclave. Such toxic materials may be captured by use of the autoclave. Conventional aggregate mining merely mechanically degrades the existing aggregate source and thus, if the aggregate is incorporated with heavy metals in the surrounding soils, the heavy metals will continue to be present up to and including after placement of the aggregate in the final position. In the use of dredge materials, such materials may include hydrocarbons that have been inadvertently spilled into the waterway. Use of the autoclave allows for ignition or driving off of these hydrocarbons, thus resulting in a clean material. The hydrocarbons entrained within the source material may be, in non-limiting embodiments, coal, rubber, spilled and settled oil, as well as other materials. The spread of these materials is avoided through the current disclosure; providing a beneficial use to a previously contaminated feedstock source.

[0082] Conventional aggregate production does not take a defined waste and allow for the waste to be used in an environmentally friendly manner. Conventional aggregate production merely takes a natural occurring material and uses mechanical processes to size the overall material. Such sizing and production occurs at the mine as this is the most economical method of production. Conventional aggregate production does not happen at a waste production site, such as at a dredging site. As a result, conventional aggregate production is not “mobile” but rather locked in place to where geological deposits are located. For the aggregate production to be truly “mobile”, the aggregate 28 INFORMATIONPATENT ATTORNEY DOCKET ECH-005 DREDGE COMPONENT BASED AGGREGATE AND METHOD OF MAKING AN AGGREGATE must be shipped, thereby increasing production of greenhouse gases. Aspects of the present disclosure also eliminate the transportation step required for mine-mouth operations, thereby providing a significant benefit to overall greenhouse gas emissions compared to conventional activities.

[0083] Certain detrimental effects of conventional aggregate production activities are eliminated by the present disclosure. For example, conventional aggregate production involves significant production of dust that must be handled by a producer. Dust reduction often includes spraying water on feedstock hills to minimize dust production to the local population. The United States Environmental Protection Agency has created mandates for dust control at mining sites. Worker and resident exposure to dust can result in silicosis where silicon enters a living organism’s lungs and other tissues. Such silicosis can result in cancer, difficulty breathing, and in extreme cases, death. The current processes described do not have such drawbacks as dust emissions are minimized. In some embodiments, silos are used to house the materials that are used to produce the dredge component based aggregate.

[0084] Use of such water processes is prevented as well as the energy and emissions associated with providing the power to such wetting activities. As the current disclosure provides an essentially sealed processing regime, the footprint of the processing for the current method processes is limited. Due to the wetting requirements for conventional aggregate production, mining permits also require storm water management and run-off management plans. These plans must be approved and verified by local officials. Such requirements are precluded under the disclosed process as raw materials enter the process and only a finalized product is removed (other than emissions from the autoclave). Moreover, the emissions from the autoclave may be minimized and controlled such that greenhouse gas emissions are minimized and toxic materials liberated by the process may be reused as feedstock for other processes and industries. To this end, the 29 INFORMATIONPATENT ATTORNEY DOCKET ECH-005 DREDGE COMPONENT BASED AGGREGATE AND METHOD OF MAKING AN AGGREGATE processes described herein present significant improvements over conventional aggregate production.

[0085] Aspects of the disclosure also provide significant advantages to conventional dredge activities. To this end, when dredge materials are stored on land, clean or virgin earth is required to be built into berms to house the dredge materials. After extensive use, the earthen berms may structurally subside due to settlement, wetting and drying cycles, and erosion. This may result in the dredge materials leaking from the earthen berms created and potentially contaminating large areas. Through use of the processes described, large impoundment areas are not necessary for dredge materials. The reduction in the amount of land needed for dredge materials allows local lands to be used for more beneficial purposes. Moreover, in some instances, areas of previously unusable land can be returned to a “virgin” state where the land can be used for more economically beneficial purposes.

[0086] In embodiments, the feed material is dried and screened from 35 to 500 microns. Any material larger than 35 microns will be rejected and ground down (using a ball mill) to an acceptable particle size. Screened and dry material is mixed with calcium oxide (lime) or calcium hydroxide (hydrated lime). An additional sodium hydroxide (lye) compound is added to the mixture. The mix ratio of the blend is 100 percent material with 3 percent to 15 percent calcium oxide or calcium hydroxide and 1 percent to 5 percent sodium hydroxide, based on the total weight of the material. Material is thoroughly mixed; and the finished material is malleable to touch, but not able to lose shape after molding. The mixed material is transferred into a rolling press that applies a force of 5,000 pounds per square inch to 15,000 pounds per square inch to mold the green mixture into aggregate, briquette shapes, or other desired shapes. Shapes are known as green products. The green product is transferred into a thermal curing treatment. Thermal curing 30 INFORMATIONPATENT ATTORNEY DOCKET ECH-005 DREDGE COMPONENT BASED AGGREGATE AND METHOD OF MAKING AN AGGREGATE is performed at 140 pounds per square inch to 350 pounds per square inch and 180 degrees Celsius to 225 degrees Celsius for 4-10 hours.

[0087] Embodiments may include the following alternatives or features. These include performing a preparation of the feedstock into the method. In one embodiment, the dredge materials are initially subjected to a drying process to remove moisture content. Subsequently, the dried material undergoes screening, using mechanical sieves, to achieve a particle size distribution within the range of 35 to 500 microns.

[0088] In embodiments, material particles exceeding the upper limit of 35 microns are identified and segregated for further processing as illustrated at 112. These oversized particles are directed to a ball mill, where they undergo grinding operations until they reach the desired particle size distribution.

[0089] The material from the silos at 110 may be screened. Appropriately sized dry materials are then introduced into a mixing chamber where it is blended with predetermined quantities of calcium oxide (lime) or calcium hydroxide (hydrated lime) and sodium hydroxide (lye). The proportions of these chemical compounds are adjusted to achieve the desired chemical composition and reactivity within the final product. The mixing process is carefully controlled to ensure uniform distribution of the chemical compounds throughout the material matrix.

[0090] Mixing, at 122 is then performed. The blended material undergoes thorough mixing to homogenize the mixture and ensure even distribution of the chemical additives. The resulting mixture, known as the green mixed material, possesses specific physical properties, including malleability and cohesiveness, which render it suitable for subsequent forming processes. Precise control is maintained over the mixing parameters to achieve consistent quality and performance characteristics in the final product. 31 INFORMATIONPATENT ATTORNEY DOCKET ECH-005 DREDGE COMPONENT BASED AGGREGATE AND METHOD OF MAKING AN AGGREGATE

[0091] Mixing at 122 may be performed at an indoors location, preventing dust production outside of the processing area. Air may be filtered at 122 to prevent worker safety concerns, as previously described, for generation of silicosis. Humidity control may also be present during mixing activities to keep dust generation at a minimum, if desired.

[0092] A preliminary testing of the feedstock may occur prior to using the materials in the mixing phase at 122. This testing may identify the presence of silicon within the feedstock. If present, then wetting activities may be conducted during handling of materials to prevent dust creation. If, during the preliminary testing of the feedstock, no silicon is identified (nor heavy metals), then wetting may not be needed, alleviating the necessity of a wetting procedure.

[0093] In embodiments, the green mixed material is then fed into a rolling press apparatus equipped with precision molds designed to impart the desired shape and dimensions to the final products. The material is subjected to controlled compression forces ranging from 5,000 pounds per square inch to 15,000 pounds per square inch, facilitating the formation of dense, uniform aggregates or briquettes. In some embodiments, the material may be compressed to lesser amount if aggregate with different final properties is required.

[0094] In these embodiments, the molding process uses meticulous attention to detail to ensure the accurate replication of mold geometry and the prevention of defects or inconsistencies in the finished products.

[0095] In some embodiments, following molding, the green products are transferred to a thermal curing chamber (autoclave), where they undergo a curing process to enhance their mechanical strength and durability. Thermal curing is carried out under controlled conditions, typically at temperatures ranging from 180 degrees Celsius to 225 degrees Celsius and pressures between 140 pounds per square inch and 350 pounds per square inch, for a specified duration lasting between 4 to 10 hours. During thermal curing, 32 INFORMATIONPATENT ATTORNEY DOCKET ECH-005 DREDGE COMPONENT BASED AGGREGATE AND METHOD OF MAKING AN AGGREGATE chemical reactions occur within the material matrix, resulting in the formation of stable crystalline phases and the development of interparticle bonds, thereby imparting structural integrity and dimensional stability to the final products. The thermal curing process achieves the desired performance characteristics, including compressive strength, abrasion resistance, and resistance to environmental degradation, in the finished aggregates or briquettes.

[0096] In some embodiments, the curing in the autoclave may include both the mold and the green mix material being heated. In other embodiments, the green mixture may be removed from the mold and fired directly. Molds used during the molding process may include carbon steel molds or ceramic molds as non-limiting embodiments. Molds may be reused in some applications. Prior to reuse of molds, the molds may be cleaned through action of water or sand blasting.

[0097] Complex shapes may be developed through the use of molds. In some embodiments, different mold shapes can be used to control the overall porosity of the aggregate so that engineering specifications are maintained after placement. In some embodiments, a high porosity may be desired so that water may flow through the placed aggregate at a specific rate. The use of the complex shapes may be designed with interlocking features such that the shapes are not dislodged by hydraulic forces traveling through the aggregate. If lower porosity is needed, such as for dam embankments, the complex shapes may minimize porosity, allowing for more retention of water by the aggregate. To this end, the aggregate produced by the current process may be specifically designed for a type of porosity. Common aggregate does not have such a capability. In areas requiring low porosity, the available natural resources for such material are minimal, thus driving up overall costs of production for construction. In aspects of the current methods, porosity may be defined from the start with little to no effect on costs. The end result may be low or high porosity aggregate with little differentiation in the overall cost for a project. 33 INFORMATIONPATENT ATTORNEY DOCKET ECH-005 DREDGE COMPONENT BASED AGGREGATE AND METHOD OF MAKING AN AGGREGATE

[0098] Within the autoclave, at 130, in embodiments, chemical reactions occur. The lime (calcium oxide or calcium hydroxide) and lye (sodium hydroxide) react with the fine materials present in the mixture. These reactions result in the formation of new compounds, such as calcium silicate hydrates and sodium alumino-silicates, through processes like pozzolanic reactions and alkali activation. In these embodiments, the high temperature and pressure conditions in the autoclave accelerate the hydration of lime and lye. Hydration reactions lead to the formation of calcium hydroxide and sodium hydroxide solutions, which act as activators for the clay minerals, promoting their dissolution and re-precipitation into stable crystalline structures.

[0099] In embodiments, under the applied pressure and temperature within the autoclave, the dredge material-lime-lye mixture undergoes consolidation, resulting in the formation of a dense, homogenous matrix. The combination of chemical reactions and compaction leads to the development of mechanical strength and structural integrity in the cured product.

[0100] In embodiments, microstructural changes occur. The thermal curing process induces changes in the microstructure of the material, including the refinement of pore size distribution and the formation of interlocking crystals or mineral phases. These changes contribute to the enhancement of mechanical properties such as compressive strength and durability.

[0101] The combination of chemical reactions and physical compaction facilitates the setting and hardening of the material. During curing in the autoclave, the dredge material- lime-lye mixture undergoes a transition from a plastic or malleable state to a rigid and stable form, capable of withstanding external forces and environmental conditions.

[0102] Aspects of methods described may be performed by computer-controlled equipment. As such, portions of the disclosure may be recorded onto a non-volatile 34 INFORMATIONPATENT ATTORNEY DOCKET ECH-005 DREDGE COMPONENT BASED AGGREGATE AND METHOD OF MAKING AN AGGREGATE memory system. For definitional purposes, a non-volatile memory system may be a memory system that does not wipe clean after termination of electrical power to the system. Examples of non-volatile memory systems may be compact disks, solid-state drives, and universal serial bus devices. These memory systems may be used to store program executable method steps for a computer, server, or computing arrangement. Control of such equipment and methods under the current disclosure are contemplated.

[0103] Different descriptions of the claims are recited. These descriptions should not be considered limiting. In one example embodiment, a method to produce a dredge material based aggregate is disclosed. The method comprises receiving a feedstock of dredge materials. The method further comprises separating the feedstock of materials into a size of less than 35 microns to create a separated fraction of sized dredge based components. The method further comprises combining a weighed portion of at least one of a lye and a lime amount to a measured portion of the separated fraction of sized dredge based components to create a mixture, wherein a mix ratio of 3 percent to 15 percent of one of calcium oxide and calcium hydroxide and 1 percent to 5 percent of sodium hydroxide, based on weight, is achieved. The method further comprises dry mixing the mixture to create a mixed dry mixture. The method further comprises adding water to the mixed dry mixture to create a green mixture. The method further comprises hydraulically roller pressing the green mixture into a mold to directly form a green aggregate. The method further comprises thermally curing the green aggregate in an autoclave to form the dredge component based aggregate.

[0104] In another example embodiment, the method may be performed wherein the roller press compresses the green mixture between 5,000 pounds per square inch to 15,000 pounds per square inch. 35 INFORMATIONPATENT ATTORNEY DOCKET ECH-005 DREDGE COMPONENT BASED AGGREGATE AND METHOD OF MAKING AN AGGREGATE

[0105] In another example embodiment, the method may be performed wherein the thermal curing is performed between 180 degrees Celsius to 225 degrees Celsius between 4 to 10 hours at a pressure of between 140 pounds per square inch to 350 pounds per square inch.

[0106] In another example embodiment, the method may be performed wherein a portion of the feedstock of dredge materials above 35 microns size is mechanically treated to result in an overall particle size less than 35 microns.

[0107] In another example embodiment, the method may be performed wherein the mechanical treatment is one of through an abrasion technique and a ball mill.

[0108] In another example embodiment, the method may further comprise mechanically treating the aggregate after the thermally curing of the green aggregate in the autoclave.

[0109] In another example embodiment, the method may be performed wherein the mechanical treatment is through a crushing mechanism.

[0110] In another example embodiment, the method may further comprise mechanically separating the aggregate after the crushing mechanism.

[0111] In another example embodiment, the method may be performed wherein the aggregate produced is characterized by a mineralogical crystalline phase.

[0112] In another example embodiment, the method may be performed wherein the lime is one of calcium oxide and calcium hydroxide and where the lye is sodium hydroxide. 36 INFORMATIONPATENT ATTORNEY DOCKET ECH-005 DREDGE COMPONENT BASED AGGREGATE AND METHOD OF MAKING AN AGGREGATE

[0113] In another example embodiment, the method may further comprise drying the feedstock prior to the separating.

[0114] In another example embodiment, the method may be performed wherein the aggregate has at least one of calcium silicate hydrates and sodium alumino-silicates.

[0115] In another example embodiment, the method may further comprise bagging the aggregate after the mechanical separation.

[0116] In another example embodiment, a method to produce a dredge component based aggregate is disclosed. The method may comprise receiving a feedstock of dredge component materials. The method may further comprise separating the feedstock of dredge component materials into a size of 35 microns or less to create a separated fraction of dredge component materials. The method may further comprise combining a weighed portion of at least one of a calcium oxide, calcium hydroxide, and sodium hydroxide to a weighed portion of the separated fraction of dredge component materials to create a mixture, wherein a mix ratio of 3 percent to 15 percent of one of calcium oxide and calcium hydroxide and 1 percent to 5 percent sodium hydroxide based on weight. The method may further comprise dry mixing the mixture. The method may further comprise mixing the mixture with water to create a green mixture. The method may further comprise roller pressing the green mixture into a pre-shaped mold to directly form a formed shape. The method may further comprise thermally curing the formed shape in an autoclave at a temperature between 180 degrees Celsius and 225 degrees Celsius, and a pressure of 140 pounds per square inch and 350 pounds per square inch, and where heavy metals are driven off from the green mixture. The method may further comprise crushing the formed shape to an aggregate size material after the thermal curing. 37 INFORMATIONPATENT ATTORNEY DOCKET ECH-005 DREDGE COMPONENT BASED AGGREGATE AND METHOD OF MAKING AN AGGREGATE

[0117] In another example embodiment, the method may be performed wherein portions of the feedstock above the size of 35 microns are mechanically abraded to a new size of less than 35 microns prior to adding the new sized portion to the separated fraction.

[0118] In another example embodiment, the method may further comprise mechanically separating the crushed aggregate size material into finalized size portions.

[0119] In another example embodiment, the method may be performed wherein the thermally curing to formed shape includes forming at least one of silicate hydrates and sodium alumino-silicates.

[0120] In another example embodiment, the method may be performed wherein the separating the feedstock into a size of 35 microns or less to create a separated fraction of sized material is performed through mechanical sieves.

[0121] In another example embodiment, the method may further comprise storing the separated fraction in a silo prior to weighing.

[0122] In another example embodiment of the disclosure, a construction material based upon dredge materials is disclosed. The material includes a molded formed aggregate with a homogenous matrix of calcium silicate hydrates and sodium alumino-silicates with a stable crystalline structure formed into an aggregate shape.

[0123] The foregoing description of the embodiments has been provided for purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosure. 38 INFORMATIONPATENT ATTORNEY DOCKET ECH-005 DREDGE COMPONENT BASED AGGREGATE AND METHOD OF MAKING AN AGGREGATE Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but, where applicable, are interchangeable and can be used in a selected embodiment, even if not specifically shown or described. The same may be varied in many ways. Such variations are not to be regarded as a departure from the disclosure, and all such modifications are intended to be included within the scope of the disclosure.

[0124] While embodiments have been described herein, those skilled in the art, having benefit of this disclosure, will appreciate that other embodiments are envisioned that do not depart from the inventive scope. Accordingly, the scope of the present claims or any subsequent claims shall not be unduly limited by the description of the embodiments described herein. 39 INFORMATION

Claims

PATENT ATTORNEY DOCKET ECH-005 DREDGE COMPONENT BASED AGGREGATE AND METHOD OF MAKING AN AGGREGATE CLAIMS What is claimed is:

1. A method to produce a dredge component based aggregate, comprising: receiving a feedstock of dredge materials; separating the feedstock of materials into a size of less than 35 microns to create a separated fraction of sized dredge based components; combining a weighed portion of at least one of a lye and a lime amount to a measured portion of the separated fraction of sized dredge based components to create a mixture, wherein a mix ratio of 3 percent to 15 percent of one of calcium oxide and calcium hydroxide and 1 percent to 5 percent sodium hydroxide based on weight is achieved; dry mixing the mixture to create a mixed dry mixture; adding water to the mixed dry mixture to create a green mixture; hydraulically roller pressing the green mixture into a mold to directly form a green aggregate; and thermally curing the green aggregate in an autoclave to form the dredge component based aggregate.

2. The method according to claim 1, wherein the roller press compresses the green mixture between 5,000 pounds per square inch to 15,000 pounds per square inch.

3. The method according to claim 1, wherein the thermal curing is performed between 180 degrees Celsius to 225 degrees Celsius between 4 to 10 hours at a pressure of between 140 pounds per square inch to 350 pounds per square inch. 40 INFORMATIONPATENT ATTORNEY DOCKET ECH-005 DREDGE COMPONENT BASED AGGREGATE AND METHOD OF MAKING AN AGGREGATE 4. The method according to claim 1, wherein a portion of the feedstock of dredge materials above 35 microns size is mechanically treated to result in an overall particle size less than 35 microns.

5. The method according to claim 4, wherein the mechanical treatment is one of through an abrasion technique and a ball mill.

6. The method according to claim 1, further comprising mechanically treating the aggregate after the thermally curing of the green aggregate in the autoclave.

7. The method according to claim 6, wherein the mechanical treatment is through a crushing mechanism.

8. The method according to claim 7, further comprising mechanically separating the aggregate after the crushing mechanism.

9. The method according to claim 1, wherein the aggregate produced is characterized by a mineralogical crystalline phase.

10. The method according to claim 1, wherein the lime is one of calcium oxide and calcium hydroxide and where the lye is sodium hydroxide.

11. The method according to claim 1, further comprising drying the feedstock prior to the separating.

12. The method according to claim 1, wherein the aggregate has at least one of calcium silicate hydrates and sodium alumino-silicates.

13. The method according to claim 8, further comprising bagging the aggregate after the mechanical separation. 41 INFORMATIONPATENT ATTORNEY DOCKET ECH-005 DREDGE COMPONENT BASED AGGREGATE AND METHOD OF MAKING AN AGGREGATE 14. A method to produce a dredge component based aggregate, comprising: receiving a feedstock of dredge component materials; separating the feedstock of dredge component materials into a size of 35 microns or less to create a separated fraction of dredge component materials; combining a weighed portion of at least one of a calcium oxide, calcium hydroxide, and sodium hydroxide to a weighed portion of the separated fraction of dredge component materials to create a mixture, wherein a mix ratio of 3 percent to 15 percent of one of calcium oxide and calcium hydroxide and 1 percent to 5 percent sodium hydroxide based on weight; dry mixing the mixture; mixing the mixture with water to create a green mixture; roller pressing the green mixture into a preshaped mold to directly form a formed shape; thermally curing the formed shape in an autoclave at a temperature between 180 degrees Celsius and 225 degrees Celsius and a pressure of 140 pounds per square inch and 350 pounds per square inch and where heavy metals are driven off from the green mixture; and crushing the formed shape to an aggregate size material after the thermal curing.

15. The method according to claim 14, wherein portions of the feedstock above the size of 35 microns are mechanically abraded to a new size of less than 35 microns prior to adding the new sized portion to the separated fraction. 42 INFORMATIONPATENT ATTORNEY DOCKET ECH-005 DREDGE COMPONENT BASED AGGREGATE AND METHOD OF MAKING AN AGGREGATE 16. The method according to claim 14, further comprising mechanically separating the crushed aggregate size material into finalized size portions.

17. The method according to claim 14, wherein the thermally curing to formed shape includes forming at least one of silicate hydrates and sodium alumino- silicates.

18. The method according to claim 14, wherein the separating the feedstock of dredge materials into a size of 35 microns or less to create a separated fraction of sized dredge materials is performed through mechanical sieves.

19. The method according to claim 14, further comprising storing the separated fraction in a silo prior to weighing.

20. A construction material based upon a dredge component material, comprising: a molded formed aggregate with a homogenous matrix of calcium silicate hydrates and sodium alumino-silicates with a stable crystalline structure formed into an aggregate shape. 43 INFORMATION

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