Systems & methods for closed-loop contamination capture and remediation

Abstract

A closed-loop system and method for on-site remediation of contaminated fluids integrates selective separation media with plasma electrocoagulation (PEC) and multi-stage reverse osmosis (RO). Contaminated fluid contacts capture media, such as ion exchange resins or adsorbent resins, which concentrate target contaminants including cyanide, metals, PFAS, and organics into a regeneration fluid. The concentrated fluid is treated in a PEC reactor where plasma discharge electrochemically destroys or coagulates contaminants. A filtration module removes precipitated solids, and a multi-stage RO subsystem comprising BWRO, SWRO, and OARO stages may recover and concentrate salt from the filtered fluid, returning highly concentrated reject fluid to the capture media as rinsing fluid. The synergistic integration of PEC and selective separation media enables high contaminant destruction efficiency, closed-loop salt recovery, negligible waste generation, and modular deployment without off-site transport.

Description

[0001] Docket No.: 00182 / 060 SYSTEMS & METHODS FOR CLOSED-LOOP CONTAMINATION CAPTURE AND REMEDIATION CROSS REFERENCE TO RELATED APPLICATIONS

[0002] The present application claims priority to United States Provisional Application Serial No.

[0003] 63 / 749,824 filed on January 27, 2025, to United States Provisional Application Serial No.

[0004] 63 / 754,327 filed on February 5, 2025, and to United States Provisional Application Serial No.

[0005] 63 / 847,931 filed on July 21, 2025, the contents of all of which are incorporated herein by reference in their entireties.

[0006] FIELD OF THE INVENTION

[0007] The invention relates to water treatment and waste remediation, and more specifically to systems and methods for on-site capture, electrochemical destruction, and remediation of contaminants using capture media, plasma electrocoagulation (PEC), filtration, and closed-loop salt recovery via multi-stage reverse osmosis (RO).

[0008] BACKGROUND

[0009] Contaminated fluids such as groundwater, mine tailings, industrial wastewater, and produced water from oil extraction frequently contain diverse pollutants, including metals, cyanides, hydrocarbons, per- and polyfluoroalkyl substances (PFAS), and other organic and inorganic substances. The chemical diversity of these contaminants can render conventional treatment complex and expensive.

[0010] Traditional remediation approaches typically involve addressing single pollutants, concentrating pollutants for transport off-site to centralized processing facilities, or concentrating and isolating pollutants for long-term storage either onsite or at offsite locations, requiring specialhandling, containment, and safety precautions, and creating significant risk, regulatory burden, and cost. Sometimes, as a result of treatment, the problem of storing or disposing of concentrated waste or treatment by-products remains. In many cases, contaminated fluid is simply sealed and stored on-site in containment ponds or tanks, but this is not a sustainable long-term solution and does not address the underlying contamination.

[0011] Different classes of contaminants, such as metals, cations, anions, inorganics, and organics, have distinct chemical properties and reactivity. Consequently, conventional treatment systems require multiple, separate processing stages, each targeting a specific contaminant class. These multi-stage systems can consume large volumes of chemicals and energy, generate wastes that require handling and storage, or utilize treatment media or other consumables that result in high operational costs.

[0012] One conventional treatment process employs selective separation media, also referred to herein as capture media, to capture and concentrate specific classes of contaminants from a contaminated fluid while allowing the bulk fluid to pass through. Ion exchange (IX) is an established method of using capture media to remove dissolved ions from water. Similarly, adsorbent resins remove non-ionic organic contaminants from contaminated fluid through physical adsorption onto a porous surface rather than chemical exchange. However, IX requires periodic chemical regeneration, using concentrated salt brine or an acidic or basic reagent, and adsorbent resins require regeneration using heat, steam, or chemicals. Each of these regeneration processes produce a contaminated fluid that must itself be treated or disposed of.

[0013] Electrocoagulation is a water treatment technique in which electrical current is passed between submerged electrodes to generate coagulant species and destabilize contaminants. Systems and methods of plasma electrocoagulation (PEC), a more energetic form ofelectrocoagulation that generates plasma discharge with electro-chemical reactivity within the liquid, are known in the art. An exemplary PEC system is described in United States Patent No.

[0014] 10,941,058 to Lalli, which is incorporated herein by reference in its entirety. PEC achieves superior contaminant removal efficiency compared to both conventional electrocoagulation and stand-alone plasma treatment, but has not previously been integrated with ion exchange and other media capture systems.

[0015] Reverse osmosis (RO) is widely used for water desalination and purification. However, conventional RO reaches practical concentration limits due to osmotic pressure constraints. Recent advances in Osmotically Assisted Reverse Osmosis (OARO) enable concentration beyond conventional saturation limits, but OARO has not been applied to salt recovery for closed-loop remediation processes in conjunction with IX.

[0016] While electrocoagulation as a general technique is known in the art, it has not achieved widespread adoption in industrial wastewater treatment due to significant practical limitations. Conventional electrocoagulation systems must be physically large to achieve adequate residence time, and the energy requirements for treating high volumes of low-conductivity wastewater can be prohibitively expensive. As a result, electrocoagulation has remained impractical for many industrial applications.

[0017] Similarly, while adsorption resins and other capture media are known for removing contaminants from fluids, the use of such media as part of a two-step process, wherein contaminants are first captured and concentrated by the media, then subsequently destroyed by PEC means, is not known to have been demonstrated or applied at industrial scale. Prior art systems employing adsorption resins simply regenerate the media and discharge the contaminatedregeneration fluid, creating a secondary waste stream that must be separately treated or disposed of.

[0018] There is a great and unsolved need in the fluid remediation industry for more cost-effective treatment solutions. The high cost of conventional remediation technologies has resulted in contaminated fluids from mining, industrial processes, oil and gas production, and other sources being only partially treated, stored indefinitely in containment ponds, or released into the environment. This widespread practice of deferring or avoiding treatment due to cost represents a significant environmental and public health concern.

[0019] As such, there remains an unmet need for an integrated, energy -efficient, modular, closed-loop process capable of remediating contaminated fluid at its source, with no required off-site transport, minimal chemical consumption, negligible waste generation, and continuous re-use of consumable materials such as salt and regeneration fluids. Specifically, there is a need for a system that combines capture and concentration of contaminants with electrochemical destruction in a synergistic manner that overcomes the limitations of each technology when used alone.

[0020] SUMMARY

[0021] A system and method are disclosed that integrate selective separation media with plasma electrocoagulation (PEC) and optional multi-stage reverse osmosis (RO) for closed-loop contamination capture and remediation. The system provides continuous, on-site treatment of contaminated fluids without requiring off-site transport and without generating significant waste.

[0022] In one aspect, a system for remediating fluid having at least one contaminant comprises a contaminant processing unit that receives contaminated fluid and separates at least one contaminant from the fluid to produce a contaminant-concentrated fluid, a PEC reactor that receives the concentrated fluid and generates plasma in situ within the concentrated fluid to destroyand / or coagulate the contaminant to form a contaminant-reduced fluid, and a fdtration module configured to remove the destroyed and / or coagulated contaminants from the contaminant-reduced fluid to produce a filtered fluid.

[0023] The contaminant processing unit may comprise capture media including ion exchange (IX) resins configured to capture anionic contaminants (such as Strong Base Anion resins), IX resins configured to capture cationic contaminants (such as Strong Acid Cation resins), and / or adsorbent resins configured to capture non-ionic organic contaminants. The filtration module may comprise an ultrafilter, a settling tank, a cartridge filter, a microfiltration membrane, an ultrafiltration membrane, and / or a nanofiltration membrane.

[0024] In some embodiments, the system further comprises a reverse osmosis subsystem configured to alter the salt concentration of the filtered fluid to yield a concentrated reject brine for return to the system and a desalinated effluent. The reverse osmosis subsystem may comprise a plurality of stages arranged in series to recover and increasingly concentrate salt from the filtered fluid. In preferred embodiments, the reverse osmosis subsystem includes an Osmotically Assisted Reverse Osmosis (OARO) stage configured to recover increasing concentrations of salt by applying a controlled salt gradient on a permeate side of a plurality of membranes to reduce osmotic pressure differential across each membrane, enabling concentration of the reject brine to greater than 100,000 mg / L chlorides. A recirculation loop may return at least a portion of the concentrated reject brine from the reverse osmosis subsystem to the contaminant processing unit as rinsing fluid, enabling closed-loop salt recovery.

[0025] The system may comprise a plurality of treatment arms arranged in parallel and / or in series, wherein each treatment arm comprises a contaminant processing unit, a plasma reactor, and a filtration module, and wherein the plurality of treatment arms share a common reverse osmosissubsystem. Tn one configuration, a first treatment arm comprises SBA resin configured to capture anionic contaminants including cyanide, and a second treatment arm comprises SAC resin configured to capture cationic contaminants including metals.

[0026] Additional system features may include a dosing module positioned between the plasma reactor and the filtration module to introduce reagents into the contaminant-reduced fluid to precipitate residual contaminants, a pre-filtration module positioned upstream of the contaminant processing unit to remove suspended solids and particulates from the contaminated fluid prior to contact with the selective separation media, and modular deployment on one or more skids enabling transport and installation at remote or temporary sites.

[0027] The system is effective for remediating fluid containing contaminants including cyanide, metals, organics, hydrocarbons, arsanilic acid, cobalt cyanide complexes, gasoline range organics (GRO), diesel range organics (DRO), polychlorinated biphenyls (PCBs), per- and polyfluoroalkyl substances (PFAS), volatile molecules, semi-volatile molecules, dissolved cations, and dissolved anions.

[0028] In another aspect, a method for remediating contaminated fluid having at least one contaminant comprises contacting the fluid with a contaminant processing unit configured to capture the contaminant in a selective separation media, eluting the contaminant processing unit with a rinsing fluid to produce a regeneration fluid containing the contaminant at elevated concentration, generating plasma discharge in situ within the regeneration fluid using a plurality of electrodes in a plasma electrocoagulation reactor to destroy and / or coagulate the contaminant and produce a contaminant-reduced fluid, filtering the contaminant-reduced fluid to remove the destroyed and / or coagulated contaminants and produce a filtered fluid, and processing at least aportion of the filtered fluid through a reverse osmosis subsystem to produce a concentrated reject brine and a desalinated effluent.

[0029] The reverse osmosis subsystem may comprise Brackish Water Reverse Osmosis (BWRO), Salt Water Reverse Osmosis (SWRO), and OARO stages arranged in series. Processing through the OARO stage may comprise applying a controlled salt gradient on a permeate side of an RO membrane to enable concentration of the reject brine to greater than 100,000 mg / L chlorides.

[0030] In preferred embodiments, the selective separation media concentrates the target contaminants in the regeneration fluid by a factor of approximately 40 to 50 times relative to initial influent concentration, the rinsing fluid comprises sodium chloride at a concentration ranging from 50,000 to 100,000 mg / L, and the regeneration fluid has a total dissolved solids concentration of approximately 100,000 mg / L. A majority of salt consumed during eluting the selective separation media may be recovered by the reverse osmosis subsystem and returned to the contaminant processing unit, enabling closed-loop operation with reduced external salt supply.

[0031] Where the target contaminants comprise cyanide species, generating plasma discharge converts the cyanide species to gaseous products comprising carbon dioxide, nitrogen gas, and nitrogen oxides. Where the target contaminants comprise dissolved metal cations, generating plasma discharge causes the metal cations to form insoluble precipitates comprising metal hydroxides and metal oxides.

[0032] The method may further comprise passing the contaminated fluid through a first treatment arm comprising a first contaminant processing unit containing a resin to capture anionic contaminants, and passing intermediate contaminated fluid from the first treatment arm through a second treatment arm comprising a second contaminant processing unit containing a resin to capture cationic contaminants.In some embodiments, the method comprises continuously passing the contaminated fluid through a plurality of selective separation media, each targeting different contaminants, and releasing contaminant-free fluid after passage through the plurality of selective separation media. Subsequently, each of the plurality of selective separation media is eluted with rinsing brine to advance concentrated contaminants through their respective treatment arms comprising plasma electrocoagulation and filtration. This batch capture mode enables efficient processing wherein contaminants are first captured across all media in series, the treated fluid is discharged, and then each media is regenerated to produce concentrated regeneration fluids that proceed through their respective PEC and filtration modules.

[0033] The method may also comprise recirculating at least a portion of the contaminant-reduced fluid through the plasma electrocoagulation reactor for additional treatment cycles, and adjusting retention time based on real-time sensor feedback comprising conductivity, pH, temperature, and / or turbidity measurements.

[0034] The closed-loop contamination capture and remediation system and method, together with their particular features and advantages, will become more apparent from the following detailed description and with reference to the appended drawings.

[0035] BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram of a first embodiment of a closed-loop contamination capture and remediation system, illustrating two modular treatment arms operating in series to process contaminated influent.

[0036] FIG. 2 is a block diagram of the system of FIG. 1, showing the components of the PEC module.FIG. 3 is a block diagram of a second embodiment of the system of FIG. 1, illustrating the path of a metal s-contaminated fluid through two modular treatment arms, wherein a first arm captures and remediates anionic particles and a second arm captures and remediates metals.

[0037] FIG. 4 is a block diagram of a second embodiment of the system of FIG. 3, showing the serial configuration of the reverse osmosis system, wherein filtered fluid passes through a Brackish Water Reverse Osmosis (BWRO) module, a Salt Water Reverse Osmosis (SWRO) module, a holding tank, and an Osmotically Assisted Reverse Osmosis (OARO) module, and wherein the brine tanks of each treatment arm also feed the holding tank.

[0038] FIG. 5 is a block diagram of the OARO subsystem of FIG. 4, showing the operational stages and flow paths within the subsystem.

[0039] FIG. 6 is a table showing representative flow rates of feed, permeate, and reject streams for the BWRO, SWRO, and OARO subsystems of the RO module of FIG. 4.

[0040] Like reference numerals refer to like elements throughout the several views of the drawings.

[0041] DETAILED DESCRIPTION

[0042] As shown in the accompanying drawings, the present invention is directed to systems and methods for closed-loop contamination capture and remediation. The system 10 provides an efficient method of treating contaminated fluids directly at their source using a sequence of selective chemical and electrochemical processes. The system 10 is capable of processing contaminated fluids containing any concentration of total dissolved solids (TDS). As used herein, the terms “contaminated fluid” and “influent” shall be used interchangeably, and shall refer to wastewater of all types, including mine tailings, produced water, industrial wastewater, gray water, military or municipal waste streams, wastewater that results from industrial processes,manufacturing processes, oil and gas production, medical procedures, municipal or sewage water, or other impure liquid that may contain suspended solids, oils, emulsions, organics, refractory organics, inorganics, minerals, heavy metals, and microorganisms that is in need of purification and / or decontamination. “Treated fluid” or “effluent” shall be used interchangeably with each other, and shall refer to wastewater of any category identified above which has undergone treatment in the closed-loop system 10 described herein. The terms “contaminated fluid” and “wastewater” may be used interchangeably, although it should be understood that “contaminated fluid” may be any liquid not limited to wastewater. It should be understood that various fluids of the system are referred to herein; however, depending on the capture media and other features of a given system, the fluid used in the system may be a brine or a non-saline fluid. Where the properties of a given target contaminant are appropriate, “fluid” and “brine” may be used interchangeably. “Plasma electrocoagulation” or “PEC” are processes which occur via a “plasma electrocoagulation reactor,” “plasma reactor,” or “PEC reactor,” these terms shall be used interchangeably with each other and shall refer to the treatment of fluid by the systems for and methods of plasma electrocoagulation described herein.

[0043] The system 10 treats contaminated fluids directly at their source, eliminating the need for transportation to off-site facilities. This reduces transportation costs and logistics, safety risks associated with handling and transporting hazardous materials, regulatory compliance burden for off-site waste disposal, and time delay between contamination and remediation.

[0044] Referring to FIG. 1, a closed-loop contamination capture and remediation system 10 is provided that is used for the treatment of contaminated fluid using integrated modules. Each module processes the influent using various materials and techniques, including capture media, PEC, filtration, and reverse osmosis (RO), with varying embodiments including some or all of themodules. The system 10 may be provided as a standalone treatment unit or integrated into a larger contaminated fluid treatment facility. The system 10 may be mounted on one or more skids or support structures to facilitate transport and installation at remote or temporary sites. The skid may include attachment points for securing the system components and enabling relocation as needed.

[0045] Through various combinations of process modules, the system 10 simultaneously addresses multiple contaminant classes that typically require separate treatment technologies. The modular design of the system 10 enables phased deployment to match treatment demand growth, parallel operation of multiple treatment arms for increased capacity, serial operation of complementary arms for multi-contaminant scenarios, and site-specific customization without redesigning core components.

[0046] The system features a recirculation loop 20 that enables continuous, closed-loop operation of the system 10. As contaminated fluid passes through the treatment arms, portions of the treated stream may be redirected back to upstream modules at the start of a treatment arm, providing salt brine necessary for the operation of some process modules. This internal recirculation enables the recovery and return of concentrated salt brine within the system 10 and provides flexibility to route brine or other fluids between treatment arms based on real-time contaminant profiles and system conditions. The recirculation loop 20 may operate in conjunction with various flow control valves and a control panel to dynamically balance flow rates, retention times, and treatment intensity across all modules, ensuring that the system 10 achieves target contaminant destruction and salt recovery efficiencies while minimizing energy consumption and consumable usage.

[0047] Valves within the system 10 may be used to isolate regeneration fluid within the recirculation loop 20 as it passes through the capture media 120, PEC module 200, and filtration module 400. “Regeneration fluid” may interchangeably be referred to as a “concentrate” herein.Additionally, valves may be configured to isolate and recirculate fluids within individual modules. For example, regeneration fluid may be recirculated through only the PEC module 200 for a given treatment time, wherein the regeneration fluid passes through the PEC reactor 210, undergoes mixing, and then recirculates through the PEC reactor 210 again. Recirculation may also occur through a combination of a plurality of modules, such as the PEC module 200 and filtration module 400 together, or an entire treatment arm may recirculate, or the system 10 as a whole may operate in recirculation mode.

[0048] The present invention represents a significant advance over prior art water treatment systems through its integration of established technologies into a novel, synergistic closed-loop system 10 that achieves outcomes not possible with any technology alone or in conventional combinations.

[0049] Each individual technology employed in the system 10, capture media, PEC, filtration, and RO, has inherent limitations when operated independently that are overcome through their integration in the present system 10. Capture media 120 operates most efficiently with regular regeneration, but regeneration produces burdensome waste streams that must be treated or disposed of. However, in the present system 10, this regeneration waste becomes advantageous because PEC operates most effectively with a concentrated starting point. Electrochemical destruction of contaminants by PEC is inefficient at low contaminant concentrations, to the point that very low concentrations cannot be effectively eliminated. However, when starting at high concentrations, the residual low-end concentration that is not eliminated becomes negligible relative to the original contamination level. The low residual concentration not destroyed by PEC continues through the system 10, where it is re-captured or destroyed in subsequent treatment cycles.The capture media 120 concentrates contaminants in the regeneration fluid by a factor of approximately 40 to 50 times relative to the initial influent concentration. This concentration effect dramatically improves PEC efficiency. For example, the amount of energy required to destroy 10 ppm of a given contaminant down to 3 ppm is substantially the same as the amount of energy needed to destroy 5,000 ppm of that contaminant down to 10 ppm. The concentration of contaminants in the regeneration fluid upstream of PEC treatment substantially improves the efficiency of the PEC module 200 and the system 10 as a whole.

[0050] The concentration effect also reduces the total volume of fluids processed in the recirculation loop 20 by orders of magnitude depending on the contaminants and concentrations being addressed, with a factor of 40 to 50 times being the norm, relative to normal flow-through treatment using the PEC module 200 alone. This combined effect of higher concentration and lower volume is significant. For example, 500 gpm of contaminated fluid with 100 ppm of a given contaminant becomes 10 gpm of regeneration fluid with 5,000 ppm of that contaminant. After PEC treatment, in this example, the 10 gpm stream at 5,000 ppm becomes 10 gpm at approximately 10 ppm. This residual contaminant remains in the recirculation loop 20 and regeneration fluids and may return to the capture media 120 for re-capture.

[0051] The concentration effect and reduced volume in the regeneration loop 20 allows the PEC reactor 210 to be physically smaller and to consume less power compared to systems treating fullvolume, low-concentration streams directly. This represents a significant capital and operating cost advantage.

[0052] In some embodiments, the capture media 120 may require regeneration slightly more frequently when regenerated using recycled rinsing fluid containing residual contaminants, compared to regeneration using fresh rinsing fluid. This results in a minor efficiency loss in capturemedia 120 capacity, calculated as the ratio of remaining contaminant concentration to the starting concentration of contaminant in the influent. In preferred embodiments, these efficiency losses are less than 2%, and usually less than 0.2%, representing a negligible trade-off for the substantial benefits of closed-loop operation.

[0053] Additionally, the system 10 can recover commercially valuable metal solids that can offset operational costs, including cobalt, nickel, gold, and other metals found in contaminated fluid. Metals are recovered in highly concentrated, easily processed forms suitable for metallurgical extraction.

[0054] Contaminated fluid may enter the system 10 from multiple sources. In some embodiments, influent is drawn directly from a contamination source, such as a well, mine tailings pond, or industrial process stream. In other embodiments, contaminated fluid is first collected in a holding reservoir or tank prior to treatment, allowing for batch processing and / or flow rate management. The system 10 includes at least one influx port 12 in fluid communication with a treatment arm of the system 10 through which influent enters the system 10. The influx port 12 connects to tubing, piping, hoses, channels, or conduits suitable for transferring contaminated fluids. In a preferred embodiment, influent initially travels through the system to a target contaminant processing unit. In a preferred embodiment, this unit is the capture module 100. In alternate embodiments, multiple influx ports 12 may be provided to accommodate different contamination sources, to separate contaminated fluid processing for each module, or to enable parallel processing streams.

[0055] The system 10 may comprise one treatment arm or a plurality of treatment arms. In preferred embodiments, the system 10 includes as many treatment arms as there are distinct target contaminant classes in the influent. Influent to any given treatment arm may be drawn from the contaminated fluid source or may be received from a recirculation loop 20. For example, aninfluent containing cyanides, metals, and organic contaminants may be treated by a system 10 having three treatment arms: one configured for cyanide capture and destruction, one for metal capture and coagulation, and one for organic particle capture and destruction. In preferred embodiments, the capture module 100 of each treatment arm is configured with capture media 120 specifically selected for its target contaminant class, followed by treatment in a PEC module 200 optimized for destroying or coagulating that contaminant class.

[0056] In some embodiments, a pre-filtration module 110 is positioned between, and in fluid communication with each of, the influx port 12 and the first treatment arm to initially remove and capture suspended solids and large particulates that could foul the capture media 120, as part of the target contaminant processing unit. Accordingly, only influent having dissolved solids continues through the system 10. This pre-filtration may employ screen filters or strainers to remove large debris, cartridge filters or bag filters for intermediate-size particles, multimedia filters comprising sand, anthracite, and garnet for fine particulate removal, and / or self-cleaning crossflow filters with large particle, small particle, or ultrafiltration membranes for submicron particles and colloids. The filtration threshold, including pore size or particle size cutoff, is selected based on the media specifications and influent characteristics. Material captured by the pre-filtration module 110 may be returned to the contaminated fluid source for natural settling or set aside as solid waste for separate disposal. The pre-filtration module 110 reduces the contaminant load entering the capture module 100, extending the operational life of the capture media 120 and improving overall system 10 efficiency.

[0057] The system 10 includes at least one efflux port 14 in fluid communication with the interior of the system 10, through which treated fluid exits the system 10. The efflux port 14 may connect to tubing, piping, hoses, channels, or conduits suitable for transferring effluent to a discharge pointfor environmental release, a holding reservoir or tank, or secondary or tertiary treatment systems such as filtration or disinfection. Multiple efflux ports 14 may be provided at various stages of treatment to allow intermediate streams to be separately collected or routed from each process module.

[0058] The system 10 is designed with a modular architecture, wherein each major treatment step is provided as a discrete, independent process module that may be deployed individually or in combination. Each module may be containerized for protection, winterization, and ease of transport. Each module may be skid-mounted to facilitate rapid deployment and relocation. Each module may be scaled independently to match site-specific requirements. Modules may be operated in parallel with duplicate modules to increase treatment capacity. Modules may be operated in series with complementary modules to address multiple contaminant classes sequentially. For example, a site treating both cyanide and metals contamination may deploy two parallel treatment arms: one comprising a capture module 100 having tailored capture media 120 and a PEC module 200 for cyanide destruction, and another comprising a capture module 100 having tailored capture media 120 and a PEC module 200 for metal coagulation. Both arms may share other process modules, such as a common RO salt recovery module 600.

[0059] Modularity enables partial deployments where initial capacity is installed and additional modules are added incrementally as treatment demand increases or as additional contaminant classes are identified. The modularity of the system 10 further includes the ability to locate different processing steps at different physical site locations, as well as the ability to skip certain processing steps or repeat processing steps as needed for particular contamination scenarios. In some embodiments, each step of the treatment process is performed at a different physical location, with various fluids of the system 10 transported between locations by tanker, pipeline, hoses, orother means. Tn some embodiments, an entire treatment arm, portions of each treatment arm, or each individual module of a treatment arm may be physically separable and operated independently, enabling maximum flexibility in deployment and maintenance.

[0060] The retention time refers to the duration that contaminated fluid remains in contact with treatment media in the capture module 100, plasma discharge in the PEC module 200, reagents in a dosing module 300, or fdters in the fdtration module 400. Retention time is a critical parameter affecting treatment efficacy. Retention time may be adjusted by varying influent flow rate, wherein decreasing the rate at which new contaminated fluid enters the system 10 increases the residence time of fluids already in the system 10. In some embodiments, retention time adjustment is automated through a control panel based on real-time sensor feedback including conductivity, pH, temperature, contaminant concentration, turbidity, or other measurements.

[0061] Retention time may also be adjusted by intra-module recirculation, wherein at least a portion of fluid exiting a module, such as the PEC module 200, may be redirected back into that module for additional treatment cycles. Where a fluid may benefit from an additional round of treatment, a redirection loop 30 may be provided in fluid communication with a module or a plurality of modules, allowing feedback for fluid to undergo multiple passes through one or more process modules. The proportion of fluid directed into the redirection loop 30 versus proceeding to the next treatment module may be controlled by flow control valves, providing fine-tuned retention time adjustment. This redirection is particularly beneficial for fluids with low conductivity or high contaminant concentrations, where extended treatment time enhances contaminant removal and destruction.

[0062] The system 10 is scalable to accommodate a wide range of contaminated fluid volumes. Representative flow rates include small-scale systems processing up to 100 gallons per minute(gpm), medium-scale systems processing 100-1,000 gpm, and large-scale systems processing 1,000 gpm or more. Flow rates at each step of the system 10 depend on the target contaminant and the specific treatment requirements for each module. Flow rates through individual process modules may differ from overall system 10 flow rates. For example, while the capture modules of the system 10 may process 2,000 gpm of influent, individual capture modules 100 may operate at 500 gpm each, with four capture modules 100 operating in parallel. Similarly, the recirculation loop 20 or redirection loop 30 may operate at a different flow rate than the primary influent stream, with the combined flows meeting at a confluence point at or upstream from a given treatment arm to optimize treatment efficacy for specific contaminant profiles.

[0063] The target contaminant capture module 100 employs selective separation media, also referred to herein as capture media 120, to capture and concentrate specific contaminants from the contaminated fluid. Capture media 120 is any media with properties suitable to selectively capture and discharge or otherwise separate particles, whether based on charge or other physical properties of those particles. The term capture media 120 as used herein encompasses any capture and concentration technology known in the art, including but not limited to ion exchange resins, adsorption resins, nanofiltration membranes, ultrafiltration membranes, RO membranes, activated carbon, oleophilic media, and any other media capable of selectively retaining and subsequently releasing target contaminants. In preferred embodiments, contaminants from a contaminated fluid are captured using any such capture media 120 and are delivered to the PEC module 200 for electrochemical destruction or coagulation. The capture module 100 operates on the principle of selective affinity, where contaminants bind to or are absorbed by the capture media 120 based on their chemical or physical properties. The influent passes through the capture media 120 of eachtreatment arm without the targeted contaminant and either exits the efflux port 14 of the system 10 or continues through the system 10 for further processing.

[0064] The target contaminant capture module 100 may comprise one or more separation columns, vessels, or reactors containing the capture media 120. Multiple target contaminant capture modules 100 may be arranged in series to sequentially remove different contaminant classes, or in parallel to increase treatment capacity or address different contamination streams simultaneously. In some embodiments, additional capture media 120 steps may be added in a given treatment arm to capture particles having different physical properties within that treatment arm, allowing for more comprehensive contaminant removal when the influent contains a diverse mixture of contaminants.

[0065] Ion exchange (IX) resins 120 are known in the art and may be employed within the capture unit 100 to selectively capture ionic and in some cases organic complexes. IX resins 120 contain functional groups that reversibly exchange ions with the surrounding fluid.

[0066] Strong Base Anion (SB A) resins 120 are used to capture negatively charged contaminants by initially holding ions such as chloride and exchanging those ions for negatively charged contaminants when influent contacts the resin 120. SB A resins 120 are known to effectively capture cyanide (CN‘) and related species such as thiocyanate (SCN’) and cyanate (OCN), per-and polyfluoroalkyl substances (PFAS), and anionic species such as sulfate (SO42), carbonate (CO32), and nitrate (NCL"). Commercially available SBA resins 120 suitable for the present invention include Purolite™ resins (Ecolab Purolite LLC, King of Prussia, PA) and AmberLite™ resins (DuPont de Nemours, Inc., Wilmington, DE). Weak Base Anion (WBA) resins 120 may also be employed as an alternative or supplement to SBA resins 120 depending on the content of the influent.Strong Acid Cation (SAC) resins 120 are used to capture positively charged contaminants, such as metal ions, by initially holding ions such as sodium and exchanging those ions for positively charged contaminants when influent contacts the resin 120. SAC resins 120 effectively capture transition metals including cobalt (Co2+), nickel (Ni2+), copper (Cu2+), zinc (Zn2+), and iron (Fe2+ / Fe3+), heavy metals including lead (Pb2+), cadmium (Cd2+), and mercury (Hg2+), alkaline earth metals, and metalloids including arsenic (AS37AS5 1). Commercially available SAC resins 120 suitable for the present invention include Purolite™ resins (Ecolab Purolite LLC, King of Prussia, PA) and AmberLite™ resins (DuPont de Nemours, Inc., Wilmington, DE). Weak Acid Cation (WAC) resins 120 may also be employed as an alternative or supplement to SAC resins 120 depending on the content of the influent.

[0067] For non-ionic organic contaminants, polymeric adsorbent resins 120 are employed within the capture module 100. Unlike ion exchange resins, adsorbent resins 120 capture contaminants through physical adsorption onto a porous surface rather than chemical exchange. Polymeric adsorbents 120 such as the AmberLite™ adsorbents (DuPont de Nemours, Inc., Wilmington, DE), Dowex Optipore™ adsorbents (The Dow Chemical Company, Midland, MI) and Purolite™ PAD and MN adsorbent families (Ecolab Purolite LLC, King of Prussia, PA) provide macro- and microporous structures for capturing hydrocarbons including benzene, toluene, and xylene (i.e., BTX compounds), gasoline-range organics (GRO) and diesel-range organics (DRO), polychlorinated biphenyls (PCBs), PFAS compounds, volatile organic compounds (VOCs) and semi-volatile organic compounds (SVOCs), cyanide, arsanilic acid, cobalt cyanide complexes, and other short and long chain molecules. Specific products suitable for use in the capture module 100 include DuPont Amberlite™ ROC 110 oil-coalescing media (DuPont de Nemours, Inc., Wilmington, DE) for removing oil and organics from industrial wastewater.Activated carbon 120 may also be employed within the capture module 100 for organic contaminant removal, particularly for PFAS compounds, benzene and other aromatics, chlorinated organics, and taste and odor compounds. Oleophilic resins 120 are selective for dissolved and emulsified oils and may be employed where petroleum contamination is present. While ion exchange and adsorption are the primary separation mechanisms, the capture module 100 may also incorporate other chemical or physical separation techniques based on target contaminant properties, including extraction, distillation, chromatography, evaporation, crystallization, filtration for particulates, sedimentation, and precipitation.

[0068] Once the selective media 120 in the capture module 100 becomes saturated with captured contaminants, it must be regenerated to restore its capacity. Regeneration involves eluting or removing the captured contaminants from the media 120 using a rinsing fluid or other elution fluid. For ion exchange resins 120, regeneration employs high-ionic-strength solutions that displace captured contaminants through mass action. The same sodium chloride (NaCl) rinsing fluid may be used to regenerate both SBA and SAC resins 120. For SBA resins 120 capturing anionic contaminants, high-concentration chloride solution (NaCl brine) is passed through the resin 120, chloride ions (O') displace captured anions, and the resin 120 is returned to its chloride form ready for reuse. Lowering the pH of the rinsing fluid with hydrochloric acid (HC1) may enhance elution efficiency. For SAC resins 120 capturing metal cations, high-concentration sodium solution (NaCl brine) is passed through the resin 120, sodium ions (Na+) displace captured metal cations, and the resin 120 is returned to its sodium form ready for reuse. Raising the pH of the rinsing fluid with sodium hydroxide (NaOH) may enhance elution efficiency.

[0069] For polymeric adsorbent resins 120, the regeneration method depends on the specific resin 120 and contaminant. Steam may be used to thermally desorb captured organics and hydrocarbonsfrom resins such as Dowex Optipore™ adsorbents (The Dow Chemical Company, Midland, MI), while solvent elution may be preferable for other applications. Adsorbent resins 120 have been shown to reversibly bind certain contaminants, including cyanide complexes, when heat is applied. The steam regeneration effluent from polymeric adsorbent resins 120, condensed as regeneration fluid, contains desorbed contaminants at elevated concentrations. In a preferred embodiment, this is advantageous because this steam condensed as regeneration fluid continues through the treatment arm to the PEC module 200 for contaminant destruction and is subsequently recycled through another treatment arm before having the opportunity to exit the system 10.

[0070] The result of regeneration for any IX module is a relatively small volume, targetcontaminant-concentrated regeneration fluid containing the captured contaminants. This concentrated stream can be transferred to the PEC module 200 for contaminant destruction or coagulation. Typical rinsing fluid concentrations range from 50,000 to 100,000 mg / L of sodium chloride. The IX regeneration process consumes salt as ions are exchanged with the capture media 120. In a representative operation, rinsing fluid with an initial chloride concentration of 100,000 mg / L may be reduced to approximately 70,000 mg / L after passing through and regenerating the IX media 120, representing approximately 30% salt donation to the process. The system 10, including the multi-stage RO module 600, recovers this donated salt, enabling closed-loop operation.

[0071] In some embodiments, an additional RO module may serve as the capture media 120 of a treatment arm. When RO is employed as capture media 120, contaminated fluid is pressurized through the RO membrane, producing permeate that is substantially free of contaminants and reject as regeneration fluid that is highly concentrated with target contaminants. In a preferred embodiment, this regeneration fluid continues down the treatment arm to the PEC module 200 forcontaminant destruction or coagulation. RO capture media 120 is particularly effective for capturing and concentrating metals and cyanide species. The use of RO membranes as capture media 120 upstream of PEC treatment provides an alternative or supplementary capture mechanism to ion exchange and adsorption resins 120.

[0072] In an alternative embodiment, steam regeneration may be employed to elute contaminants from adsorbent resins 120 or other suitable capture media 120. In this configuration, the system 10 can include a steam generator 130 that produces steam for use as rinsing fluid, or can use steam available on location. The term “rinsing brine” refers to a salt-containing solution used for elution while “rinsing fluid” refers to non-saline water converted to steam used for elution. The various fluids described herein may be brines if salt solutions are applicable or desirable for the elution step of a given capture media 120. For example, a “rinsing fluid” for IX media requiring salt for regeneration should be understood to be a “rinsing brine.” Steam regeneration is an example of a “rinsing fluid” which is not a “rinsing brine.” The steam generator 130 is positioned upstream of or integrated with the capture module 100 and provides steam at sufficient temperature and pressure to thermally desorb captured contaminants from the capture media 120. The steam passes through the capture media 120, volatilizing and carrying away the captured organic compounds and other thermally-desorbable contaminants. After regeneration, the contaminated steam is directed to a condensing tank 140 where it is cooled and condensed back into liquid form. This condensate, contains the desorbed contaminants at elevated concentrations. The condensing tank 140 serves as an interface between the capture module 100 and the PEC module 200, collecting the contaminant-concentrated condensate and delivering it to the PEC reaction chamber 210 for electrochemical destruction or coagulation. This steam-based regeneration approach is particularlyeffective for volatile organic compounds, semi-volatile organic compounds, and hydrocarbons that readily desorb under thermal treatment.

[0073] In other embodiments, steam regeneration is employed to elute contaminants from adsorbent resins 120 or other suitable capture media 120, but a saline brine is still used in the remainder of the system 10 or treatment arm. Non-saline steam is produced by the steam generator 130, used as a rinsing fluid, and then condensed in the condensing tank 140. However, the condensed steam is either mixed with a brine or has salts added to make it into a saline brine. This is done depending on the target contaminant’s reactivity in later modules, such as the PEC module 200. In embodiments using steam regeneration and a saline brine, an additional RO module 600' is included in the relevant treatment arm to treat the recirculation loop 20 between the relevant treatment arm and the steam generator 130. The single treatment arm shown in FIG. 2, which may be part of a larger system 10, implements this method. FIG. 2 shows capture media 120 which is regenerated by steam from the steam generator 130, where the steam used in regeneration is sent to the condensing tank 140 and is mixed with solid salts or other brine prior to continuing to the PEC module 200. As shown in FIG. 2, a PEC holding tank 220 is positioned downstream from the PEC module 200 and features a feedback loop 30 between the PEC holding tank 220 and the condensing tank 140 so that fluids can continuously be run through the PEC reactor 210 for a treatment period, after which the contaminant-reduced fluid continues to the fdtration holding tank 410 and fdtration module 400, which together feature their own feedback loop 30. After fdtration, a brine tank 500 and dedicated RO module 600' for this application are provided. This RO module 600' regenerates non-saline fluid for the steam generator 130, to be continuously run through this treatment arm or a plurality of relevant treatment arms of the system 10. RO reject may return to the condensing tank 140 to mix with the next round of condensed steam regeneration fluid.The plasma electrocoagulation (PEC) module 200 receives the target-contaminant-concentrated regeneration fluid from the capture module 100 and subjects it to high-energy plasma discharge within a PEC reaction chamber 210. The PEC module may consist of a plurality of PEC reactors arranged in parallel or in series. In a preferred embodiment, the PEC module 200 consists of a PEC reactor as described in U.S. Patent No. 10,941,058, which is incorporated herein by reference. The plasma discharge simultaneously generates multiple physical and chemical effects that destroy or coagulate contaminants. These effects include electrochemical oxidation and reduction reactions that break down organic molecules and convert toxic species to benign products, coagulation of dissolved metals through formation of insoluble hydroxides and oxides, generation of free radicals and reactive species including hydroxyl radicals and other reactive particles that attack contaminants, UV emission that damages organic molecules and inactivates microorganisms, and cavitation and shock waves that enhance mixing and mass transfer. Unlike conventional electrocoagulation, which operates at low voltages typically less than 10 V, the PEC reactor 210 applies sufficient voltage to generate plasma discharge within the liquid phase, resulting in markedly more efficient treatment.

[0074] The PEC reaction chamber 210 has an interior space configured to receive and retain any contaminated fluid during treatment. The reactor 210 may be constructed of electrically non-conductive materials such as plastic, fiberglass, acrylic, or other materials suitable for containing the fluid and withstanding the plasma environment. The PEC module 200 includes an influx port in fluid communication with the upstream portion of the system 10. In preferred embodiments, the capture module 100 is upstream from the PEC module 200 and passes contaminated regeneration fluid to the influx port. The reactor 210 also includes an efflux port through which contaminant-reduced fluid, treated by the PEC module, exits for downstream processing. The reactor 210includes a plurality of plasma-producing electrodes which extend into the interior space of the reactor 210 and are submerged in fluid during operation. Electrical connections extend from the electrodes to an external power source, which may be an independent power source for the PEC module or a power source shared with the system 10. The PEC reactor 210 may be mounted on a skid or housed within a protective enclosure for transport and weatherization.

[0075] The PEC reactor 210 electrodes are electrically conductive and capable of donating metal ions during electrocoagulation while simultaneously generating plasma discharge. Electrodes may be made of any suitable electrically conductive material, including but not limited to iron, aluminum, palladium, and titanium. In preferred embodiments, electrodes have an elongate cylindrical shape, such as a rod or wire, that focuses electrical energy at terminal ends, facilitating plasma generation. Electrodes may be straight or curved, with terminal ends optionally angled toward each other to enhance plasma arc formation. The diameter of the electrodes may be in the range of 1 mm to 35 cm, preferably 3 mm to 30 mm, and more preferably 6 mm to 15 mm. The spacing between adjacent electrodes may be in the range of 1 cm to 3 cm, preferably 2 cm. The number of electrodes is typically in multiples of 3 for three-phase AC power. In three-phase AC configurations, electrodes receiving different phases are positioned adjacent to one another to ensure uniform plasma generation throughout the reactor 210.

[0076] In some embodiments, electrodes are at least partially surrounded by insulating material that focuses electrical energy to specific portions of the electrode surface. The insulating material may comprise plastics, polytetrafluoroethylene (PTFE, such as Teflon®), resins, epoxies, or polymeric materials including latex and acrylics. The insulating material leaves the terminal end of each electrode exposed, concentrating plasma generation at that location. As plasma is generated, the insulating material burns at a predictable rate of approximately 1 cm / hr underoptimal conditions and peels away from the electrode, gradually exposing additional surface area. This provides a controlled mechanism for regulating the rate of electrocoagulation and electrode consumption.

[0077] The power source supplies electrical energy sufficient to generate plasma discharge at the electrode surfaces in contact with the regeneration fluid. As described in U.S. Patent No.

[0078] 10,941,058, plasma generation in liquids requires substantially higher voltages than conventional electrocoagulation, but disproportionately lower amperage. The applied voltage depends primarily on fluid conductivity, which is a function of total dissolved solids content. The high salt and contaminant concentration of the regeneration fluid enables efficient plasma generation at relatively low voltages compared to low-conductivity wastewaters, providing a significant operational advantage.

[0079] In addition, the PEC module 200 or recirculation loop 20 may include a ground downstream of the PEC reactor 210 to discharge stray voltage. Since, in preferred embodiments, some contaminant-reduced fluid exiting the PEC reactor 210 will be recirculated back into a PEC module 200 of the system 10, the conduit or piping upstream of the PEC module 200 may also include a ground to discharge stray voltage.

[0080] A control panel may maintain constant power, constant voltage, or constant current, with the other parameters varying according to the relationship Power = Voltage x Current. As the ionic character of the fluid changes during treatment, automated adjustment of these parameters maintains optimal plasma generation.

[0081] Plasma discharge may occur as corona discharge, also known as plasma glow, which is visible as a glow of light surrounding the electrode tips that occurs at moderate energy levels, works more slowly, but conserves electrode material. Plasma discharge may also occur as plasmaarcing, which manifests as bright beams connecting electrode tips or connecting an electrode to a point in solution, occurs at higher energy levels, works more rapidly, but consumes electrodes faster. Both modes are effective for contaminant treatment, with the preferred mode depending on treatment objectives, available energy, and electrode lifespan considerations.

[0082] When working with freshwater influent or other low-conductivity fluids, higher voltages may be required in the PEC reactor 210 to generate effective plasma discharge due to the reduced ionic strength of the fluid. In some embodiments, the addition of an oxidant, such as hydrogen peroxide (H2O2), to the PEC reactor 210 has been found to allow reduced operational voltages, lead to faster contaminant degradation, and generate more flocculent for removal. The oxidant may be introduced directly into the reaction chamber 210 or into the fluids upstream of the PEC module 200. The synergistic combination of plasma discharge with oxidant addition enhances the generation of reactive species, including hydroxyl radicals, that attack and break down contaminants.

[0083] For metal remediation, electrodes in the PEC reactor 210 operate at voltages in the range of 100-400 volts to generate effective plasma discharge for coagulation reactions. If a metal species contaminant can coagulate in the presence of pH adjustment, flocculant, and coagulant, then PEC treatment will be effective. In testing, PEC has been shown to reduce metal contaminants to parts per billion levels. The known coagulation properties of metals can be used to predict treatment success in the system 10. When metal-laden fluid is treated in the PEC reactor 210, the plasma discharge and metal ion donation from the electrodes drive coagulation reactions. Dissolved metal cations react with hydroxide ions and donated electrode metals to form insoluble precipitates including metal hydroxides such as Co(OH)2, Ni(0H)2, and Fe(OH)3, metal oxides, and mixed metal complexes. These precipitates coagulate into flocculent, also referred to as floc. The chargedstate of the metal-laden fluid further induces a separation between the fluid and the contaminant(s) within the fluid. When the floc reaches a critical mass, it becomes heavier than water and sediments to the bottom of the fluid.

[0084] As more floc forms and settles, the turbid wastewater becomes increasingly clarified and clearer. The conductivity level of the fluid may decrease as fewer contaminants remain dissolved therein. Accordingly, as the conductivity levels fall, the voltage or power of the PEC reactor 210 will need to be increased to compensate and maintain a consistent level of electrocoagulation. Necessary adjustments to the PEC reactor may be made manually by an operator, but preferably may be performed automatically, such as by the control panel based on information received from the sensors and flow meter. PEC produces floc that is more resistant to fdtration extrusion than chemical treatment and conventional electrocoagulation floc, resulting in superior solid-liquid separation. The floc may be removed by a traditional clarification step or by other appropriate methods.

[0085] When fluid contaminated with organic or inorganic molecules is treated in the PEC reactor 210, the plasma discharge drives electrochemical oxidation and reduction reactions that break down toxic compounds into benign products. The high-energy plasma environment generates reactive species that attack and degrade organic molecules. The plasma discharge also produces UV emission that damages organic molecules and destroys microorganisms.

[0086] The system 10 provides a method of reducing any contaminant that can be electrochemically oxidized, such as cyanide (CN‘), hydrogen sulfide (H2S), ammonia (NH3, particularly in the presence of chlorides), total petroleum hydrocarbons, gasoline-range organics (GRO), diesel-range organics (DRO), arsanilic acid, and similar contaminants, down to approximately 10 ppm range of residual concentration. If aggressive oxidants such as free radicalchlorine, hypochlorite, sodium hydroxide, ozone, and similar species can attack a given contaminant, experimental data indicates that the contaminant will follow the destruction curve observed in the system 10. Accordingly, the known reactivity of contaminants with these oxidants can be used to predict success in the system 10.

[0087] Additionally, during treatment in the PEC reactor 210, gases may be formed. These gases may include hydrogen, oxygen, nitrogen, and carbon dioxide depending on the contaminants being treated. Gases are released from the PEC reactor 210 through venting valves or dedicated gas release ports. Proper venting ensures safe operation and prevents pressure buildup within the reactor.

[0088] In this manner, metals and other contaminants are effectively “destroyed” by the system by being released as gases or pulled out of solution and into a compact sludge. In conventional methods of removing metals from contaminated fluids, treatment of a given volume of contaminated fluid produces large volumes of metal-contaminated liquid waste that must be separately disposed of. In contrast, the present system 10 dramatically reduces waste volume. For example, treatment of a given volume of metals-contaminated fluid may produce only a small quantity of metal-rich sludge at hundredths of the volume of the treated fluid, rather than hundreds of gallons per minute of contaminated liquid waste using methods known in the art. This dramatic reduction in waste volume is a significant advantage of the integrated capture-PEC approach. The propensity of PEC-treated wastes to resist extrusion under pressure and filtration also lends them to be more efficiently dewatered, effectively reducing the volume requiring handling even further.

[0089] As described in U.S. Patent No. 10,941,058, PEC consumes significantly less electrode material per unit of treatment compared to conventional electrocoagulation. The high-energy state of the plasma causes donated metal ions to be more reactive with contaminants, enabling a givenmass of electrode to perform substantially more work. For example, cylindrical electrodes with 6.5 mm diameter can perform the same treatment as ten square feet of electrode plates in conventional electrocoagulation systems, representing a dramatic reduction in electrode consumption and reactor 210 size. Furthermore, the high ionic strength of the regeneration fluid in certain embodiments of this invention enables low-voltage plasma generation, reducing overall power consumption compared to treating low-conductivity wastewaters.

[0090] The present invention leverages a unique operational advantage in that the regeneration fluid from ion exchange has naturally high salt content of 50,000-100,000 mg / L, which dramatically enhances PEC efficiency. High conductivity enables low-voltage plasma generation for reduced power consumption per unit volume treated, more stable and controllable plasma discharge, and enhanced electrochemical reaction kinetics. This represents a non-obvious application of the PEC technology described in U.S. Patent No. 10,941,058 to the treatment of high-salinity capture media regeneration fluid.

[0091] As described in U.S. Patent No. 10,941,058, plasma electrocoagulation requires far less electrode material and reactor 210 volume than conventional electrocoagulation. When integrated with selective capture media 120 in the capture module 100, the combined system 10 achieves compact reactor 210 designs suitable for containerization, reduced energy consumption relative to conventional treatment systems, and rapid deployment capability when compared to conventional treatment plants.

[0092] In some embodiments, such as that shown in FIG. 3, a dosing module 300 is positioned between the PEC module 200 and the filtration module 400. In a preferred embodiment, the dosing module 300 features a dose tank configured to introduce reagents into the contaminant-reduced fluid that will bond with known particles remaining after treatment in the PEC module 200 andprecipitate them out of solution. However, the dosing module 300 may act on any fluid or influent within the system 10 to add desired reagents. The specific reagents introduced in the dosing module 300 are customized based on the known particles present in the fluid to be treated, based on the composition of the fluids in a given system 10. In some embodiments, the regeneration fluid may be sufficiently processed by the PEC module 200 alone such that the dosing module 300 is not required, and the contaminant-reduced fluid, which has been treated by the PEC module 200 proceeds directly to the filtration module 400. The inclusion or omission of the dosing module 300 depends on the specific contaminants present in the influent and the treatment requirements for a given application.

[0093] The system 10 includes at least one power source in electrical communication with the PEC module. The power source may generate direct current (DC) or alternating current (AC) electrical energy, which may be single phase or multiphase, such as three-phase AC. Additional power sources or one power source may also supply different subsystems, sensors , valves , and pumps of the system 10. The power source is capable of supplying sufficient electrical energy to generate plasma discharge within the contaminated fluid. As described in U.S. Patent No.

[0094] 10,941,058, plasma generation in liquid requires higher voltages than conventional electrocoagulation, typically in the range of 10 to 800 volts depending on fluid conductivity. The power source may supply electrical energy in the range of 150 VAto 1 MVA, with preferred ranges of 1 to 10 kVA for small to medium-scale systems. Current may range from 5 to 500 amperes depending on the number, size, and configuration of electrodes in the PEC reactor 210 and other demands of the system 10. A control panel may set and maintain constant power, constant voltage, or constant current.In some embodiments, the system 10 includes at least one ground exposed to the fluid flow path. The ground may be a solid copper wire or other electrically conductive grounding material, where one end is exposed to the fluid stream and the opposite end runs to electrical ground. The ground dissipates any stray voltage remaining in the fluid after treatment, enhancing safety and preventing electrical interference with downstream components.

[0095] The filterable flocculent generated from the PEC module or other reactions in the system 10 is removed by the system 10. In a preferred embodiment, the system 10 includes a filtration module 400 downstream of the PEC module 200 to separate solids from the contaminant-reduced fluid. In exemplary embodiments, the filtration module 400 following the PEC module 200 is an ultrafilter, such as those used in ultrafiltration systems known in the art, which use water pressure and a semi-permeable membrane to remove larger particles. Ultrafilters are conventionally employed almost exclusively for total suspended solids (TSS) filtration. The coagulation reactions in the PEC module 200 cause contaminants to precipitate and settle into TSS, which can then be captured by the ultrafilter. This immediate filtration catches microparticles from the PEC module 200 after treatment rather than requiring the PEC-treated contaminant-reduced fluid to sit in holding tanks to allow settling and coagulation over time, thereby reducing the physical footprint of the system 10. The pressure employed in ultrafiltration is relatively lower than that used in RO systems, making ultrafiltration effective for removing floc from the contaminant-reduced fluid while consuming less energy than RO-based separation. Additional filtration methods include settling tanks with or without clarifier plates, cartridge filters or bag filters, microfiltration membranes with pore sizes of approximately 0.1 micron, ultrafiltration membranes with pore sizes of approximately 0.01 micron, nanofiltration membranes with pore sizes of approximately 0.001 micron, or RO units. Importantly, even nanofiltration membranes have pore sizes large enough toallow passage of dissolved salt ions such as sodium (Na+) and chloride (O’), ensuring that the salt brine used for regeneration is preserved through the filtration process while particulate contaminants are removed. The selection of filtration method depends on the specific contaminants present, the particle size distribution of the floc, and the downstream processing requirements. In some embodiments, the effluent from the PEC module 200 is transferred to a settling tank upon exiting the PEC reactor 210, to allow the floc settle to the bottom. Such settling tank may include settling plates or other structures to facilitate the formation and separation of the floc from the contaminant-reduced fluid. The separated solids may be dewatered to reduce volume and, in the case of metal-rich sludge, may be processed for metal recovery. Metals such as cobalt, nickel, and gold have commercial value and may be extracted from the sludge through conventional metallurgical techniques. The filtered fluid produced by the filtration module 400, now substantially free of target contaminants, then proceeds to a brine tank for holding, the RO module 600 for salt recovery (if applicable), a treatment arm of the system 10, or any combination of the foregoing.

[0096] The system may include brine tanks 500 for holding filtered fluid and / or reject brine from the RO module 600. A “brine tank” of the system 10 does not necessarily contain a saline brine, depending on the target contaminant. In an exemplary embodiment, the system 10 includes two treatment arms with cross-feeding brine tanks 500a, 500b. Each treatment arm includes, in sequence, a capture module 100, a PEC module 200, an optional dosing module 300, a filtration module 400, and a brine tank 500a, 500b at the end of the treatment process that holds semi-depleted filtered fluid. The first treatment arm is configured to capture anions from the influent using anion exchange capture media 120, such as SB A resin or WBA resin, and allows remaining particles, including cations such as metals, to transfer to the second treatment arm. The secondtreatment arm is configured to capture cations, such as metals, using cation exchange capture media 120, such as SAC resin or WAC resin. In this embodiment, the semi-depleted filtered fluid in the brine tank 500a for the first treatment arm feeds into the capture media 120 of the second treatment arm for regeneration, and the semi -depleted filtered fluid in the brine tank 500b from the second treatment arm feeds into the capture media 120 of the first treatment arm for regeneration. This cross-feeding arrangement enables efficient use of the semi-depleted filtered fluid, as the ionic composition of the fluid from each arm is complementary to the regeneration requirements of the other arm. Particularly, sodium ion -rich filtered fluid from the brine tank 500a of the first treatment arm is suitable for regeneration of the SAC resin 120 of the second treatment arm and chloride ion-rich filtered fluid from the brine tank 500b of the second treatment arm is suitable for regeneration of the SBA resin 120 of the first treatment arm.

[0097] Filtered fluid exits the brine tanks 500 for use as rinsing fluid in regenerating the capture media 120 of the capture module 100. The regeneration fluid containing the eluted contaminants is what moves to the PEC module 200 for the next treatment step. In some embodiments, each treatment arm terminates in its own dedicated brine tank 500a, 500b, while in other embodiments multiple treatment arms share a common brine tank 500. The choice of dedicated versus shared brine tanks depends on the ionic composition requirements of each arm and the cross-feeding optimization strategy employed.

[0098] The RO module 600 includes one or more stages of RO filtration. In a preferred embodiment, the RO module 600 includes a multi-stage RO subsystem which receives feed water from the various process streams of the system and recovers and concentrates sodium chloride therein, enabling closed-loop salt regeneration. The feed water received by each RO subsystem stage may be fluid treated by the initial module of each treatment arm, which may still exceeddischarge limits, filtered fluid resulting from each treatment arm, fluid from the recirculation loop 20, and / or permeate from upstream RO stages for sequential concentration. The RO module 600 produces low-TDS permeate suitable for discharge as effluent of the system 10 and highly concentrated RO reject brine returned to the treatment arms of the system, such as to capture media 120 of the capture modules 100 as rinsing fluid.

[0099] Unlike conventional ion exchange systems that require continuous external salt supply, the RO module 600 recovers and recycles the majority of consumed salt, significantly reducing the need for continuous external salt supply, reducing operational costs, and enabling closed-loop operation. However, in some embodiments, salt recovery may not be necessary for cost-effective operations, and the RO module 600 may be omitted entirely depending on site-specific factors such as salt availability, disposal costs, and discharge requirements. This novel use of Osmotically Assisted Reverse Osmosis (OARO) in the OARO subsystem 630 to achieve extreme brine concentration is not obvious to those skilled in RO system design, as OARO is typically employed in desalination rather than salt recovery applications. Furthermore, the combination of various RO modules with salt regeneration brines as described herein is not obvious to those skilled in the art of RO system design.

[0100] In a preferred embodiment, as shown in FIG. 3, the RO module 600 comprises three sequential subsystem stages, each optimized for a specific concentration range. The first stage is the Brackish Water Reverse Osmosis (BWRO) subsystem 610, the second stage is the Salt Water Reverse Osmosis (SWRO) subsystem 620, and the third stage is the OARO subsystem 630. Each stage produces a low-salinity permeate stream and a high-salinity reject stream which becomes the feed to the next stage, progressively concentrating the salt brine solution. Each of BWRO, SWRO, and OARO are known in the art, but have not been combined as described herein.The BWRO subsystem 610 receives feed water having elevated ion concentrations due to treatment processes such as salt donation during ion exchange, but is still within the brackish water range, typically 1,000-10,000 mg / L TDS. The BWRO membranes in the BWRO subsystem 610 remove the majority of dissolved salts, producing BWRO permeate at low-TDS, suitable for environmental discharge, and BWRO reject brine, typically greater than 10,000 mg / L chlorides, which is forwarded to the SWRO subsystem 620. In a representative RO module 600 treating approximately 3,000 m3 / day of contaminated fluid, feed water to the BWRO subsystem 610 is 3,074 m3 / day at 564 gpm with elevated chlorides, BWRO permeate is 2,613 m3 / day at 480 gpm and BWRO reject brine is 461 m3 / day at 85 gpm, yielding water recovery of approximately 85-90%. This high recovery rate ensures that the majority of feed water is returned to beneficial use while concentrating salts for recovery.

[0101] The SWRO subsystem 620 receives the concentrated BWRO reject brine from the BWRO subsystem 610 and further increases the salt concentration of the brine. The SWRO membranes in the SWRO subsystem 620 are designed to handle high-salinity feeds of up to 100,000 mg / L or 10% salt concentration. The SWRO subsystem 620 produces SWRO permeate at low-TDS, typically 250-300 mg / L NaCl or 150-180 mg / L CT, that can be combined with BWRO permeate and / or discharged, and highly concentrated SWRO reject brine, typically 40,000-50,000 mg / L chlorides, which is forwarded to the OARO subsystem 630. In a representative RO module 600 processing 460 m3 / day of BWRO reject brine at 85 gpm, SWRO permeate is 350 m3 / day at 65 gpm at less than 100 mg / L TDS and SWRO reject brine is 111 m3 / day at 20 gpm, yielding water recovery of approximately 70-80%. In some embodiments, the SWRO reject brine is combined with filtered fluid in a holding tank 640 before final concentration in the OARO module.In some embodiments, such as that shown in FIG. 4 multiple fluid streams are combined before flowing to the OARO module 630. The system 10 may include a dedicated blending tank 640 for this purpose to facilitate controlled mixing of streams having different salt concentrations and flow rates. In other embodiments, the blending function may be performed in the brine tanks 500 or in-line through appropriate piping configurations. In a representative holding tank 640, SWRO reject brine of approximately 111 m3 / day at 20 gpm is combined with filtered fluid of approximately 119 m3 / day at 22 gpm and with approximately 70,000 mg / L chlorides, which may comprise approximately 60 m3 / day from a cyanide treatment arm and approximately 60 m3 / day from a metals treatment arm. The combined stream has total flow of approximately 230 m3 / day at 42 gpm and blended chloride concentration of 50,000-60,000 mg / L. This blended stream feeds the OARO subsystem 630 for final concentration.

[0102] The OARO subsystem 630 represents a novel application of RO technology that enables salt concentration beyond conventional saturation limits. The OARO subsystem 630 applies a controlled salt gradient on the permeate side of the RO membrane, reducing the osmotic pressure differential across the membrane and allowing extreme concentration in the RO reject brine. In conventional RO, high feed salinity creates high osmotic pressure that opposes the applied hydraulic pressure, limiting achievable concentration. OARO overcomes this limitation by introducing salt on the permeate side, reducing the osmotic gradient and enabling reject concentrations that can exceed normal saturation and precipitation points. The OARO membranes employed in the OARO module 630 have targeted salt permeabilities that enable controlled salt transport across the membrane. In operation, salt present on the permeate side of the membrane must diffuse through the membrane support layer and substrate to reach the rejection layer, while water flux naturally washes salt away from the membrane rejection layer on the feed side. Thiscreates a salt diffusion limited process wherein the rate of salt transport, rather than hydraulic pressure, becomes the limiting factor at high concentrations.

[0103] In a preferred embodiment, the OARO subsystem 630 comprises a plurality of OARO membranes configured in stages, as shown in FIG. 5. Each stage operates with progressively higher brine concentrations on both the feed side and the permeate side of the membrane, while maintaining substantially similar osmotic pressure differentials across each membrane stage. This staged configuration enables controlled concentration increases while managing osmotic pressure limitations that would otherwise restrict conventional RO operation at extreme salinities.

[0104] Theoretically, OARO systems can achieve concentration differentials of up to 70 g / L between the concentrate and permeate streams. However, water fluxes decline rapidly with increasing brine concentrations as the osmotic pressure differential approaches the applied hydraulic pressure. Despite this decline, the salt diffusion limited operation allows the OARO subsystem 630 to maintain water fluxes between 10 to 15 liters per square meter per hour (L / m2 / h or LMH) even at high salt concentrations. Importantly, pilot plant data demonstrates that at target brine concentration levels, stage flow remains stable over time without decline, indicating that the OARO subsystem 630 can maintain consistent long-term performance when operated within design parameters. The OARO subsystem 630 produces low-TDS permeate suitable for discharge and OARO reject brine at extremely concentrated salt levels. Typically, the OARO subsystem 630 may be configured to produce OARO reject brine at more than 100,000 mg / L chlorides, which is returned to the system 10 as rinsing fluid. In a representative operation, blended stream feed water to the OARO subsystem 630 is 230 m3 / day at 42 gpm at 50,000-60,000 mg / L chlorides, OARO permeate is 103 m3 / day at 19 gpm with less than 100 mg / L TDS, and OARO reject brine is 126 m3 / day at 23 gpm with 100,000+ mg / L chlorides, with approximately 120 m3 / day returned to thesystem 10. This yields water recovery of 80-90% and salt recovery exceeding 90%. Example recovery figures for the various RO subsystems are shown in FIG. 6. The flux and reject rate of each RO stage depend on the specific ions present in the fluid being processed. The highly concentrated OARO reject brine is returned directly to the system 10, to the brine tank 500, or to an additional holding tank. In preferred embodiments, the OARO reject brine returns to the capture module 100 as rinsing fluid for the capture media 120 regeneration, completing the closed loop.

[0105] In some embodiments, RO reject brine from the RO module 600 may be selectively directed to one brine tank 500 or another depending on the balance of salts in each tank. This selective routing is controlled by valves responsive to conductivity sensors and the control panel , enabling dynamic optimization of salt balance across treatment arms. When one brine tank has a deficiency of chloride ions, for example, OARO reject brine may be preferentially routed to that tank to restore optimal salt concentration for regeneration.

[0106] In some embodiments, contaminated fluid proceeding through the first stage of each treatment arm, i.e., fluid with target contaminants removed without passing through each treatment arm, may be split between an efflux port 14 for discharge and the RO module 600 for further salt recovery and concentration. The proportion of effluent flowing directly to the efflux port 14 versus the RO module 600 is controlled by valves, which may be automatically adjusted by the control panel based on conductivity and TDS measurements. This split discharge arrangement allows for efficient operation wherein a portion of effluent having higher than acceptable levels of salts and other particles may be released directly, as the other portion of that effluent is further processed by the RO module 600. The combined outputs are designed to have acceptable levels of salts and other particles for environmental release, while maintaining system salt balance.Treatment of contaminated fluid in the system 10 may involve repetitive washes or treatments within one or more modules to achieve desired contaminant removal or destruction levels. The system 10 is configured to enable flexible treatment durations and recirculation patterns based on contaminant characteristics, concentration levels, and treatment objectives.

[0107] In some embodiments, fluid continuously flows through the PEC module 200 for a treatment duration. During this mode of operation, valves within the system 10 isolate the PEC module 200 from downstream components, and fluid exiting the PEC reactor 210 is redirected back to the PEC influx port via a redirection loop 30. The fluid repeatedly passes through the PEC reactor 210, experiencing multiple plasma discharge treatments until the target contaminant concentration is reduced to acceptable levels. Treatment duration may be determined by a fixed time period, by real-time sensor feedback indicating contaminant concentration or conductivity changes, or by a combination of time and sensor-based criteria. This repetitive treatment within the PEC module 200 is particularly effective for contaminants requiring extended plasma exposure for complete destruction, such as recalcitrant organic compounds or high concentrations of cyanide species.

[0108] In other embodiments, fluid continuously flows through an entire treatment arm for a treatment duration. In this configuration, valves isolate the treatment arm from the main system 10 flow path, and fluid exiting the filtration module 400 or brine tank 500 of that treatment arm is redirected back to the capture module 100 or PEC module 200 at the beginning of the treatment arm. The fluid repeatedly cycles through the any sequenced combination of capture, PEC treatment, and / or filtration within that arm. This arm-level recirculation enables progressive contaminant removal across multiple passes, wherein each cycle further reduces contaminantconcentration. The recirculation continues until target treatment levels are achieved, as determined by sensors, time duration, or operator input.

[0109] In still other embodiments, fluid may recirculate through a subset of modules within a treatment arm. For example, fluid may repeatedly cycle through only the PEC module 200 and filtration module 400 together, bypassing the capture module 100 during recirculation. This configuration is useful when the capture media 120 has already released its captured contaminants into the regeneration brine, and the objective is to maximize PEC destruction and solid removal without further contact with the capture media 120.

[0110] The control panel may automatically manage recirculation modes based on programmed treatment protocols or real-time optimization algorithms. In some embodiments, the control panel transitions between recirculation modes during a single treatment cycle. For example, initially recirculating fluid through the PEC module 200 alone for intensive contaminant destruction, then expanding recirculation to include the filtration module 400 for solid removal, and finally releasing the treated fluid to downstream components or discharge.

[0111] In some embodiments, contaminated fluid may continuously flow through the capture modules 100 of multiple treatment arms simultaneously for a treatment duration. In this configuration, contaminated influent enters the system 10 and is routed through the capture media 120 vessels of a plurality of treatment arms, in series and / or in parallel, such that each capture media 120 selectively removes its target contaminant class from the contaminated fluid as it passes through. The contaminated fluid continuously washes through this series of capture media 120 vessels until all target contaminants have been captured by their respective capture media 120. During this capture phase, the downstream portions of each treatment arm, which may include the PEC modules 200, filtration modules 400, and brine tanks 500, remain isolated from the influentflow. Only after the capture media 120 across all treatment arms have captured the target contaminants does the treated influent exit the system 10 through the efflux port 14.

[0112] In a preferred embodiment, the system 10 operates in a batch capture mode comprising distinct capture and regeneration phases. During the capture phase, contaminated influent continuously flows through the capture media 120 vessels of multiple treatment arms arranged in series. For example, in a system 10 treating influent containing both anionic contaminants such as cyanide and cationic contaminants such as metals, the influent first passes through the capture media 120 of a first treatment arm containing SBA resin, which captures anionic species, and then continues through the capture media 120 of a second treatment arm containing SAC resin, which captures metal cations. The contaminated fluid may recirculate through this series of capture media 120 vessels multiple times, or may pass through once at a controlled flow rate, until sensors or predetermined criteria indicate that the target contaminants have been substantially captured. The treated fluid, now substantially free of all target contaminants, exits the system 10 through the efflux port 14 for discharge or further processing.

[0113] Once the capture phase is complete, the system 10 transitions to the regeneration phase. During this phase, the capture media 120 of each treatment arm is regenerated using rinsing fluid from the brine tanks 500 and / or RO module 600. The regeneration produces a contaminantconcentrated regeneration fluid for each treatment arm, wherein the regeneration fluid from each arm contains a concentration of the specific contaminant class captured by that arm’s capture media 120. Each regeneration fluid then proceeds down its respective treatment arm to the PEC module 200 for contaminant destruction or coagulation, followed by filtration in the filtration module 400 and, if required, salt recovery in the RO module 600. Because the contaminants from a given batchof influent are concentrated into a relatively small volume of regeneration fluid, this downstream treatment is highly efficient.

[0114] In a given treatment application, this batch capture and regeneration process iterates until all contaminated influent from a source is processed. Each iteration comprises a capture phase during which a batch of influent is treated through the series of capture media 120 vessels, followed by a regeneration phase during which the capture media 120 are regenerated and the contaminantconcentrated regeneration fluids are processed through their respective treatment arms. Due to the closed-loop operation of the system following the capture phase, trace amounts of contaminants remaining following treatment do not exit the system 10. Instead, trace contaminants remain in the recirculation loop 20, brine tanks 500, or other storage areas of the system 10 and are used as rinsing fluid for one or more treatment arms to be treated again with subsequent batches of influent.

[0115] This iterative batch processing is particularly advantageous for applications involving finite volumes of contaminated fluid, such as contaminated groundwater remediation projects, industrial process waste treatment, or emergency spill response scenarios, where the objective is to process a defined quantity of contaminated fluid to meet discharge or remediation standards.

[0116] The following examples describe representative methods of operating the system 10 for treating various contaminants in accordance with embodiments of the present invention.

[0117] Referring to FIG. 1, a first embodiment of a method of using the system 10 is shown comprising a prefiltration module 110 or prefilter, two parallel treatment arms, and an RO module 600. Contaminated fluid enters the system 10 through influx port 12 and first passes through the prefiltration module to remove large particulates and suspended solids. The prefiltered fluid is then directed to a first of the two treatment arms.Each treatment arm comprises a capture module 100 containing capture media 120, a PEC module 200, a fdtration module 400, and a brine tank 500. In the capture module 100, contaminants are selectively removed from the contaminated fluid by one of the various capture media 120 described herein, producing a treated fluid stream and saturated capture media. The treated fluid stream continues to the second treatment arm without the contaminant targeted by the first treatment arm. The saturated capture media 120 is periodically regenerated using an eluent, typically concentrated rinsing fluid from the brine tank 500 of the second treatment arm and / or the RO module 600. Reagents for pH adjustment are added to optimize the regeneration. During regeneration, the eluent is transformed into a contaminant-concentrated regeneration fluid as the eluent salts replace the target contaminants captured by the capture media 120. This regeneration fluid then leaves the capture module 100 and flows or is transported to the PEC module 200. It should be understood that transport of fluids between any points of the system 10 may be by direct means, such as tubing connecting the points, or indirect means, such as being collected at a first point and transported in batches to a second point.

[0118] In the PEC module 200, the regeneration fluid is subjected to plasma discharge generated by electrodes of a PEC reactor, which drives electrochemical reactions that destroy, transform, and / or precipitate the target contaminants. The contaminant-reduced fluid from the PEC module 200 then passes, by direct or indirect means, through the filtration module 400 to remove any solid precipitates, floc, or suspended particles, producing filtered fluid that is directed to the brine tank 500.

[0119] The filtered fluid from both treatment arms is then directed to either the RO module 600 for salt recovery and concentration or the recirculation loop 20 for use as regeneration fluid. As shown in FIG. 1, the RO module 600 comprises three stages arranged in series. Each stageproduces a permeate stream with reduced salt content and a concentrate stream with increased salt content. The concentrate from each stage is passed down to the next stage for further concentration, while the final concentrate from the third stage, containing highly concentrated NaCl, is returned to the brine tank 500 or to the system 10 as regeneration fluid for the capture modules 100. The permeate streams from the RO stages, having low TDS, are combined and discharged through efflux port 14.

[0120] Inputs to the treatment arms shown in FIG. 1 include eluent (regeneration fluid from the brine tanks 500 and RO module 600) and, optionally, a pH adjuster (such as HC1, NaOH, or other acids or bases) to optimize capture media 120 operation. The use of a pH adjuster at the capture media is optional and dependent on the specific contaminant targeted and capture media used. This configuration enables closed-loop salt recycling, wherein salt consumed during capture media 120 regeneration is recovered by the RO module 600 and returned to the system 10, significantly reducing external salt requirements.

[0121] Referring to FIG. 3, a second embodiment of a method of using the system 10 for treating contaminated fluid containing both cyanide species and dissolved metals is shown. This configuration includes the features of the first embodiment with an added a dosing module 300 in the first treatment arm and specifies the types of capture media and filtration modules employed.

[0122] The capture module 100 of the first treatment arm contains SB A resin 120, which selectively captures anionic contaminants including nitrite (NCh’), cyanide (CN‘), and sulfate (SO ’) through anion exchange. The contaminated fluid is passed through the SB A resin and, as the SBA resin 120 approaches saturation, it is regenerated using concentrated NaCl rinsing brine from the brine tank 500 of the second treatment arm, optionally with pH adjustment using HC1.The regeneration produces a contaminant-concentrated regeneration fluid with cyanide and other anionic species.

[0123] This concentrated regeneration fluid flows to the PEC module 200 of the first treatment arm, where plasma discharge generated by and metal ions donated from electrodes drives electrochemical oxidation reactions. Contaminant-reduced fluid remains after the PEC module 200 treatment, and is transported to a dosing module 300.

[0124] The dosing module 300 may consist of a separate dosing tank 310 or may be a process of addition which occurs within the PEC reactor. As shown in FIG. 3, a separate dosing tank 310 is used to add calcium chloride (CaCh) to the contaminant-reduced fluid. Sulfate species then react to form calcium sulfate (CaSC ) precipitate, allowing removal of the over-concentration of sulfates from the capture media.

[0125] The output stream from the PEC module 200 and dosing module 300 of the first treatment arm, now substantially free of cyanide and containing calcium sulfate precipitate, flows to a filtration module 400. The filtration module as shown in FIG. 3 is comprised of an ultrafilter which removes the calcium sulfate precipitate and any other suspended solids from the output stream, producing a clarified filtered fluid that proceeds to the brine tank 500 and ultimately to the RO module 600 for salt recovery.

[0126] The intermediate fluid passing through the capture media 120 of the first treatment arm, now free of cyanide and anionic contaminants but potentially containing dissolved metal cations, proceeds to the second treatment arm. The capture module 100 of the second treatment arm contains SAC resin 120, which selectively captures metal cations including cobalt (Co2+), nickel (Ni2+), magnesium (Mg2+), and other metals through cation exchange. The fluid is passed through the SAC resin column and, as the SAC resin 120 approaches saturation, it is regenerated usingconcentrated NaCl brine from the brine tank 500 of the first treatment arm, optionally with pH adjustment using NaOH, producing a metal- and cation-concentrated regeneration fluid.

[0127] This concentrated regeneration fluid flows to the PEC module 200 of the second treatment arm, where plasma discharge generated by and metal ions donated from electrodes drive electrocoagulation reactions. The reactions form insoluble metal hydroxides and metal oxides. Some volatile metal species may also be released as gases. The output stream of contaminant-reduced fluid contains precipitated metal hydroxides and metal oxides in the form of dense floc.

[0128] The output from the PEC module 200 of the second treatment arm flows to a filtration module 400, which removes the solid metal hydroxides and metal oxides. The filtered solids may be dewatered and processed for metal recovery, particularly for valuable metals such as cobalt, nickel, and gold. The clarified filtered fluid proceeds to the brine tank 500 and ultimately the RO module 600 for salt recovery.

[0129] As shown in FIG. 3, the RO subsystems 610, 620, 630 receive filtered fluid from both treatment arms and operate in a multi-stage configuration similar to that shown in FIG. 1, producing low-TDS permeate for discharge and highly concentrated brine for return to the capture modules 100 as regeneration eluent.

[0130] Referring to FIG. 4, a third embodiment of a method of using the system 10 is shown, which expands upon the RO module 600 configuration of FIG. 3. The RO module 600 includes a BWRO subsystem 610, a SWRO subsystem 620, a holding tank 640, and an OARO subsystem 630.

[0131] The filtered fluid of both treatment arms flows first to the BWRO subsystem 610. The BWRO subsystem 610 produces BWRO permeate with reduced TDS suitable for discharge and BWRO reject brine with elevated salt concentration as described herein.The BWRO reject brine proceeds to the SWRO subsystem 620. The SWRO subsystem 620 produces SWRO permeate with low TDS for discharge and SWRO reject brine with further elevated salt concentration as described herein. The SWRO reject brine is directed to a holding tank 640.

[0132] In the holding tank 640, the SWRO reject brine is combined with the fdtered fluid from both treatment arms, bypassing the BWRO and SWRO subsystems, producing a blended stream of feed water for the OARO subsystem 630. This blending facilitates controlled mixing of streams having different salt concentrations and flow rates.

[0133] The blended stream from the holding tank 640 flows to the OARO subsystem 630. The OARO subsystem 630 represents a novel application of RO technology that enables salt concentration beyond conventional saturation limits by applying a controlled salt gradient on the permeate side of the RO membrane. This reduces the osmotic pressure differential across the membrane and allows extreme brine concentration in the reject stream.

[0134] The highly concentrated OARO reject brine is returned to the system 10 for use as regeneration eluent in the capture modules 100 of both treatment arms, completing the closed-loop salt recycling process.

[0135] The methods of using the integrated system 10 maintain a stable salt inventory through continuous internal recycling. Ion exchange units in the capture unit 100 donate approximately 30% of regeneration fluid salt to the treatment stream as chloride and sodium ions are exchanged for contaminants. Starting regeneration fluid at 100,000 mg / L chlorides is reduced to approximately 70,000 mg / L chlorides after being used as rinsing fluid for the capture media 120. The RO module 600 captures salt from the effluent of the capture media 120 and concentrates it through the BWRO subsystem 610, SWRO subsystem 620, and OARO subsystem 630,replenishing the salt inventory. As a result, a majority of salt consumed during fluid treatment is recovered by the RO module 600 and returned to the system 10.

[0136] In a first representative treatment example, contaminated fluid containing dissolved cyanide (CN’) species is pumped into a SBA resin 120 column in the capture module 100. The SBA resin 120 captures cyanide species through anion exchange according to the reaction Resin-C1‘ + CN’ — Resin-CN' + Cl’. Once the resin 120 approaches saturation, it is regenerated using concentrated NaCl brine at 100,000 mg / L chlorides. The regeneration produces a cyanide-concentrated regeneration fluid with cyanide concentrations significantly elevated relative to the original contaminated fluid. This concentrated regeneration fluid is pumped into a PEC reactor, generating plasma discharge at the electrode tips, and driving electrochemical oxidation according to the reaction CN' — CO2 + H2O + N2 (+ minor NO2). Experimental results demonstrate initial cyanide concentration of 3,000-6,000 mg / L in concentrated regeneration fluid and immediate posttreatment concentration of <5 mg / L. The treated fluid, now substantially free of cyanide, is filtered in the filtration module 400 to remove any suspended solids. Gaseous products including CO2 and N2 are vented safely.

[0137] When cyanide contaminated fluid is treated in the PEC reactor 210, the plasma discharge drives electrochemical oxidation that converts cyanide to benign products. The predominant reactions yield carbon dioxide (CO2), water (H2O), nitrogen gas (N2), and nitrogen oxides (NO2, N2O). Experimental data shows that cyanide concentrations can be reduced to non-detectable levels with continued plasma treatment, representing destruction efficiencies exceeding 99%, though these extreme levels are not required for operation of the system 10. Tests also showed that PEC treatment combined with hydrogen peroxide (H2O2) booster, with a small reduction in operational voltages, produced even higher cyanide destruction rates and increased floc generation.The floc was found to be filterable through standard filtration media. An ideal ratio of H2O2 to CN’ was identified for optimizing treatment efficiency, though the use of H2O2 is not required.

[0138] In PEC-only tests without SBA pre-concentration, starting cyanide concentrations of 70 mg / L were reduced to <10 mg / L, indicating incomplete oxidation and low destruction efficiencies compared to IX concentrated levels of up to 6,000 mg / L with destruction to <5 mg / L. PEC-only tests without SBA pre-concentration achieved lower removal rates of <80% even with extended testing of 5+ hours treatment time and low flow rates. The improved destruction of cyanide with SBA pre-concentration followed by PEC treatment is novel, as the reactions follow 1st and 2nd order kinetics, dependent upon experimental factors; in both cases, a higher concentration of the contaminant leads to higher PEC destruction efficiencies.

[0139] In a second representative treatment example, contaminated fluid contains both cyanide and dissolved metals. The system 10 deploys two parallel treatment arms. The cyanide arm comprises SBA resin column 120, PEC module 200 for cyanide destruction, and filtration module 400. The metals arm comprises SAC resin column 120, PEC module 200 for metal coagulation, and filtration module 400. Contaminated fluid first passes through the cyanide arm where cyanide is captured and destroyed. The intermediate fluid, now cyanide-free but still containing metals, proceeds to the metals arm where metals are captured and coagulated. Both arms share a common multi-stage RO module 600. This configuration achieves complete cyanide removal to non-detectable levels, greater than 99% metal removal with valuable metal recovery, closed-loop salt regeneration with significantly reduced external salt requirements, and treated fluid meeting discharge limits.

[0140] In a third representative treatment example, contaminated fluid containing dissolved hydrocarbons, PFAS, and other organics is passed through a column packed with polymericadsorbent resin 120 in the capture unit 100. The adsorbent resin 120 captures organics through physical adsorption onto its porous surface. Once saturated, the resin 120 is regenerated using steam, which thermally desorbs the captured organics. The desorbed organics may be condensed and collected for disposal or further treatment. For particularly recalcitrant organics such as PFAS, the desorbed concentrate may be directed to the PEC module 200 for electrochemical destruction. The high-energy plasma environment and reactive species generated, including hydroxyl radicals and other reactive particles, can break down PFAS molecules into simple fluorides, carbon dioxide, and water. This approach combines selective adsorption with PEC, providing a comprehensive solution for difficult-to-treat organic contaminants.

[0141] In this embodiment, salt-free and brine-augmented condensed fluids can be routed to the PEC module 200 for destruction, with a separate series of RO subsystems employed to capture and return brine via a feedback loop 30 for re-use in cases where re-use is desirable. Factors such as reactivity between the organic contaminants and salt brines, power consumption and efficiencies, and other factors determine the need and efficacy of employing an additional brine stage.

[0142] In a preferred embodiment, the system 10 includes a control panel in electrical communication with the various system components including pumps, valves, sensors, power sources, and an optional dedicated power source for the PEC module 200. The control panel may include an interface where an operator can operate valves and input operational parameters such as flow rates, power levels, voltage, current, and treatment duration. The control panel may also receive signals from various components of the system 10, such as the sensors and flow meter that provide information on the status of the system, and provide real-time monitoring and adjustment of system parameters. In some embodiments, the control panel includes logic circuits,programmable logic controllers (PLCs), or other appropriate electrical structures that interpret the signals and provide this information on a read-out display for viewing by an operator and / or automatically adjust system parameters based on sensor feedback, enabling automated operation with minimal operator intervention. These automatic adjustments maintain the desired settings for system 10 operation in real-time. In some embodiments, the control panel employs machine learning algorithms or artificial intelligence to control and manage the valves, sensors, operational parameters, and consumables such as electrodes and other reagent inputs to the system 10. Such machine learning or artificial intelligence systems may learn from operational data to optimize treatment efficiency, predict maintenance requirements, and adapt to changing influent characteristics over time.

[0143] For example, signals from the control panel to the power source direct the level and / or type of power generated and sent to the PEC reactor 210. The pressure or flow rate for the system 10 may also be set at the control panel, which is then communicated to the pump and valves, such as flow control valves and venting valves. One control panel may coordinate with the various components or multiple control panels may be present, and may preferably be linked together for coordinating monitoring and control.

[0144] Integrated sensors and control systems in the control panel enable fully automated operation with real-time adjustment of flow rates and retention times, power levels for plasma generation, resin regeneration scheduling, and salt balance and RO operation. This reduces labor costs and ensures consistent treatment performance.

[0145] In one embodiment, the control panel provides instructions directing how much fluid is directed into a redirection 30 loop for increased treatment or retention time in any given module, such as the PEC module 200. In other embodiments, a flow control valve may control the flowrate for the entire system 10 and may also direct the amount of fluid to be directed into the recirculation loop 20. In additional embodiments, the flow control valve works in conjunction with the control panel to determine and direct the amount of fluid passed into the recirculation loop for further treatment.

[0146] When pressure of fluid at the influx port 12 is insufficient to move that fluid through the system 10, at least one pump may be provided to move fluid through the system 10. The pump may be a centrifugal pump, positive or negative displacement pump, peristaltic pump, or any other pump suitable for moving fluids containing suspended solids and contaminants. The system 10 may include multiple pumps positioned at various points in the fluid flow path. For example, separate pumps may be provided for influent feed, recirculation loops 20, and RO module 600. Pump operation may be controlled by the control panel and may be adjusted based on system pressure, flow rate measurements, and treatment efficacy parameters. In some embodiments, pump speed is variable to allow precise control of retention time within modules of the system 10.

[0147] In some embodiments, the system 10 includes a plurality of modules working in parallel that share a common header which is in fluid communication with a single pump. For example, a plurality of PEC modules 200 may share a common header in fluid communication with a single pump. A shared pump may operate at a greater pumping rate than the flow rate of influent through each module, such as a PEC module 200. For example, the pump may operate at 2,000 gpm, and each PEC reactor 210 has influent flowing through at rates of 500 gpm. The multiple PEC modules 200 may each have the same flow rate or may have different flow rates. In other embodiments, each module of the system may connect directly to a dedicated pump. Any combination of number of pumps is contemplated herein, as may be desired for particular situations.The system 10 includes a plurality of valves disposed along the fluid flow path to regulate and direct fluid movement. The valves may include throttle valves, such as butterfly valves, that may be fully open or fully closed to control whether fluid flows through a particular section of the system 10. The recirculation loops 20 and / or redirection loops 30 may include at least one valve, such as a throttle valve, to throttle or adjust the recycle rate as necessary. Isolation valves, such as ball valves, may be positioned immediately upstream and downstream of major components, including any modules or component parts thereof, such as capture media 120 columns, PEC reactors 210, and RO modules 610, 620, 630, to isolate components for maintenance, cleaning, or replacement. Flow control valves may be partially opened along a continuum to precisely regulate flow rates through the system 10. Flow control valves may be automated and responsive to signals from flow meters and the control panel. Venting valves, such as solenoid valves, may be provided for releasing gases, vapors, or pressure that may accumulate during treatment, particularly in the PEC reactors 210 where plasma generation may produce gaseous products. Valves may be manually operated or mechanically actuated, and may be programmed or automated through the control panel.

[0148] The system 10 includes a plurality of sensors positioned throughout the fluid flow path to monitor system performance and fluid characteristics. In preferred embodiments, sensors are in electrical communication with the control panel and provide real-time data for automated system control and operator monitoring. Pressure sensors may be provided to detect system pressure and prevent over-pressurization. Temperature sensors may monitor fluid temperature and detect excessive heating that may occur during plasma generation or other treatment steps. Flow meters may measure and regulate fluid flow rates through the system 10. Conductivity sensors may measure TDS and ionic strength of the fluid, which impacts both ion exchange efficiency andplasma generation requirements. pH sensors may monitor acidity or alkalinity, particularly during resin capture and regeneration steps. In some embodiments, pH sensors are positioned within or adjacent to the capture media 120 modules to sense when acid or base reagents need to be added during capture or regeneration to maintain the capture media 120 at its optimal operating range. The pH sensors signal to the control panel to automatically dose acid reagents, such as hydrochloric acid (HC1), or base reagents, such as sodium hydroxide (NaOH), as needed to optimize contaminant capture and regeneration efficiency. While pH sensors are particularly important in the capture module 100, sensors of any type may be deployed in any module throughout the system 10 to sense ongoing parameters and signal to the control panel for adjustment. Voltage, amperage, and current sensors may be positioned at or downstream of the power source to monitor electrical energy supplied to and consumed by the PEC module 200.

[0149] The systems and methods described herein provide a comprehensive, energy -efficient, and economically viable solution for in-situ remediation of contaminated fluids containing diverse pollutant classes. By integrating selective capture media (including ion exchange resins, adsorption resins, activated carbon, oleophilic media, RO membranes, and other selective separation technologies) with plasma electrocoagulation and optional closed-loop salt recovery via multistage RO, the invention achieves complete contaminant destruction or recovery with minimal consumable requirements, negligible waste generation, and no off-site transport. The synergistic combination of these technologies produces outcomes not achievable by any single technology or conventional combination, representing a significant advance in the field of water treatment and waste remediation.

[0150] While the foregoing detailed description describes certain specific embodiments and examples, the present invention should not be limited by the specific examples provided. Sincemany modifications, variations, and changes in detail can be made to the described preferred embodiments, it is intended that all matters in the foregoing description and shown in the accompanying drawings be interpreted as illustrative and not in a limiting sense. Thus, the scope of the invention should be determined by the appended claims and their legal equivalents.

Claims

What is claimed is:

1. A system for remediating fluid having at least one contaminant, comprising:a. a contaminant processing unit receiving said fluid and separating said at least one contaminant from said fluid to produce a concentrate of said contaminant; and b. a plasma electrocoagulation reactor receiving said concentrate and generating plasma in situ within said concentrate to at least one of destroy and coagulate said contaminant, forming a contaminant-reduced fluid.

2. The system as recited in claim 1, further comprising:a. a filtration module configured to remove said at least one contaminant from said contaminant-reduced fluid to produce a filtered fluid; andb. a salt concentration in said filtered fluid and a reverse osmosis subsystem configured to alter said salt concentration to yield a concentrated reject brine for return to the system and a desalinated effluent.

3. The system as recited in claim 2, wherein said reverse osmosis subsystem comprises a plurality of stages and wherein said stages are arranged in series to recover and increasingly concentrate salt from said filtered fluid.

4. The system as recited in claim 3, wherein said reverse osmosis subsystem further comprises an osmotically assisted reverse osmosis stage configured to recover increasing concentrations of salt from said filtered fluid by a controlled salt gradient on a permeate side of a plurality of membranes to reduce osmotic pressure differential across each of said plurality of membranes.

5. The system as recited in claim 2, further comprising a recirculation loop configured to return at least a portion of said concentrated reject brine from said reverse osmosis subsystem to said contaminant processing unit as rinsing brine.

6. The system as recited in claim 2, further comprising a plurality of treatment arms, wherein each treatment arm comprises:a. a contaminant processing unit receiving said fluid and separating said at least one contaminant from said fluid to produce a concentrate of said contaminant;b. a plasma electrocoagulation reactor receiving said concentrate and generating plasma in situ within said concentrate to at least one of destroy and coagulate said contaminant, forming a contaminant-reduced fluid; andc. a filtration module configured to remove said at least one contaminant from said contaminant-reduced fluid to produce a filtered fluid; andwherein said plurality of treatment arms share said reverse osmosis subsystem.

7. The system as recited in claim 2, further comprising a dosing module positioned downstream from said plasma electrocoagulation reactor and upstream from said filtration module, said dosing module configured to facilitate introduction of reagents into the contaminant-reduced fluid for precipitation of residual contaminants.

8. The system as recited in claim 2, wherein the filtration module comprises at least one of: an ultrafilter, a settling tank, a cartridge filter, a microfiltration membrane, an ultrafiltration membrane, and a nanofiltration membrane.

9. The system as recited in claim 1, further comprising a pre-filtration module positioned upstream of said contaminant processing unit, said pre-filtration module configured to remove suspended solids and particulates from said contaminated fluid prior to processing by said contaminant processing unit.

10. The system as recited in claim 1, wherein said at least one contaminant is at least one of cyanide, metals, organics, hydrocarbons, arsanilic acid, cobalt cyanide complexes, gasoline rangeorganics, diesel range organics, polychlorinated biphenyls (PCBs), per- and polyfluoroalkyl substances (PFAS), volatile molecules, semi-volatile molecules, dissolved cations, and dissolved anions.

11. A method for remediating contaminated fluid having at least one contaminant, comprising:a. contacting said contaminated fluid with a contaminant processing unit configured to separate said at least one contaminant from said contaminated fluid in a selective separation media;b. eluting said contaminant processing unit with a rinsing fluid and producing a concentrate containing said at least one contaminant at elevated concentration;c. generating plasma discharge in situ within said concentrate using a plasma electrocoagulation reactor to at least one of destroy and coagulate said contaminant and produce a contaminant-reduced fluid; andd. filtering said contaminant-reduced fluid to remove said at least one contaminant and produce a filtered fluid.

12. The method as recited in claim 11, wherein said rinsing fluid is a rinsing brine and further comprising:a. processing at least a portion of said filtered fluid through a reverse osmosis subsystem to produce a concentrated reject brine and a desalinated effluent, wherein a majority of salt consumed during eluting said contaminant processing unit is recovered by said reverse osmosis subsystem; andb. returning said salt to said contaminant processing unit by using said reject brine as said rinsing brine, enabling closed-loop operation with reduced external salt supply.

13. The method as recited in claim 12, wherein said reverse osmosis subsystem comprises Brackish Water Reverse Osmosis (BWRO), Salt Water Reverse Osmosis (SWRO), and Osmotically Assisted Reverse Osmosis (OARO) stages arranged in series.

14. The method as recited in claim 12, wherein said reverse osmosis subsystem further comprises:a. applying a controlled salt gradient on a permeate side of a plurality of RO membranes in osmotically assisted reverse osmosis, reducing osmotic pressure differential across each of said plurality of membranes; andb. recovering increasing concentrations of salt from each of said plurality of membranes.

15. The method as recited in claim 12, wherein:a. said selective separation media concentrates said at least one contaminant in said concentrate by a factor of approximately 40 to 50 times relative to an initial concentration of said contaminated fluid; andb. said rinsing brine comprises sodium chloride at a concentration ranging from 50,000 to 100,000 mg / L.

16. The method as recited in claim 11, wherein said at least one contaminant comprises at least one of:a. cyanide species, and wherein generating plasma discharge converts the cyanide species to gaseous products comprising carbon dioxide, nitrogen gas, and nitrogen oxides; andb. dissolved metal cations, and wherein generating plasma discharge causes the metal cations to form insoluble precipitates comprising metal hydroxides and metal oxides.

17. The method as recited in claim 11 , further comprising:a. passing said contaminated fluid through a first treatment arm comprising a first contaminant processing unit containing a resin to capture anionic contaminants; and b. passing intermediate contaminated fluid from said first treatment arm through a second treatment arm comprising a second contaminant processing unit containing a resin to capture cationic contaminants.

18. The method as recited in claim 11, further comprising:a. a capture phase comprising continuously passing contaminated fluid through a plurality of selective separation media, each configured to capture a different contaminant class, until said plurality of selective separation media approaches saturation with captured contaminants, and discharging treated fluid substantially free of said contaminants; and b. a concentration phase comprising independently eluting each of said plurality of selective separation media with rinsing brine, each producing produce a respective concentrate, and processing each of said respective concentrate through their respective treatment arms comprising plasma electrocoagulation and filtration; andwherein passing said contaminated fluid through said plurality of selective separation media and advancing said contaminant-reduced brines through their respective treatment arms occur in temporally distinct phases, and wherein said capture phase and said concentration phase are repeated in iterative cycles until a predetermined volume of contaminated fluid is processed.

19. The method as recited in claim 11 , further comprising recirculating said contaminated fluid through a subset of system modules selected from a group consisting of: said plasma electrocoagulation reactor alone, said plasma electrocoagulation reactor and a filtration moduletogether, and an entire treatment arm comprising said contaminant processing unit, said plasma electrocoagulation reactor, and said filtration module.

20. The method as recited in claim 11, further comprisinga. isolating said filtration module from downstream components via one or more valves;b. recirculating at least a portion of the contaminant-reduced fluid exiting said plasma electrocoagulation reactor back to an inlet of said plasma electrocoagulation reactor via a redirection loop for additional treatment cycles; andc. continuing recirculation until a treatment endpoint is reached based on at least one of a predetermined treatment time, a predetermined sensor-based criteria, a predetermined target contaminant concentration threshold, and real-time sensor feedback comprising at least one of conductivity, pH, temperature, and turbidity measurements.

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