Abstract: An electrodialysis apparatus comprises a first reservoir wherein salt dissolved in solvent is reduced below a threshold concentration and a second reservoir wherein the salt concentration increases. A first electrode contacts a first solution of a first redox-active electrolyte material, and a second electrode contacts a second solution of a second redox-active electrolyte material. A first type of membrane is disposed between the first and second reservoirs and a second type of membrane is disposed between the first electrode and the first reservoir and between the second electrode and the second reservoir. A color measuring device is coupled to at least one of the solutions, and a control system is configured to modify the value of a property of at least one of the first and second solutions in response to detecting a color value of one of the solutions exceeding a threshold color value.

Abstract: A water treatment system is disclosed having an electrolytic cell for liberating hydrogen from a base solution. The base solution may be a solution of brine for generating sodium hypochlorite or potable water to be oxidized. The cell has first and second opposing electrode end plates held apart from each other by a pair of supports such that the supports enclose opposing sides of the end plates to form a cell chamber. One or more inner electrode plates are spaced apart from each other in the cell chamber in between the first and second electrode plates. The supports are configured to electrically isolate the first and second electrode plates and the inner electrode plates from each other. The first and second electrode plates are configured to receive opposite polarity charges that passively charge the inner electrode plates via conduction from the base solution to form a chemical reaction in the base solution as the base solution passes through the cell chamber.

Abstract: The present invention discloses a high-purity separation method of iron ions from an aqueous solution containing heavy metal ions, wherein after pretreatment of an aqueous solution containing heavy metal ions, sedimentation containing iron ions are collected, nitric acid or sulfuric acid is added for dissolution, and then a reducing agent is added to the dissolved solution; and after heating and sealing reaction, red sedimentation is generated at the bottom, The sedimentation has a high purity, and the residual amount of iron in the solution is less than 0.4 mg/L. In the method, iron ions in the solution can be converted to hematite crystals at a high purity, and the solution has an excellent retention rate of heavy metal ions, the reaction time is short, the separation efficiency is high, the operation is simple, and the cost is low.

Abstract: A method for removing selenium according to the present invention comprises: a valence change step of adding an oxidant to a wastewater from a facility that gasifies a fuel containing selenium in a reducing atmosphere, and oxidizing the selenium to change the valence of the selenium, and a solid-liquid separation step of adding a flocculant to the wastewater, forming a floc containing the selenium for which the valence has been changed in the valence change step, and subjecting the floc to solid-liquid separation.

Abstract: A system to remove contaminants from contaminated water contains a pre-concentrating subsystem, a contaminant removal subsystem or a biological subsystem configured to remove two or more contaminants, and a permeate blending subsystem. A process for removing contaminants from contaminated water includes concentrating contaminated water, treating concentrated contaminated water, and combining product water to produce environmentally acceptable product water.

Abstract: A method for making a metal oxyhydroxide electrocatalytic material comprises titrating a precursor solution with a (bi)carbonate salt, the precursor solution comprising a first metal salt and a solvent, wherein the titration induces reactions between the (bi)carbonate salt and the first metal salt to provide first metal carbonate species in the titrated precursor solution; and exposing the titrated precursor solution to microwave radiation to decompose the first metal carbonate species to form the metal oxyhydroxide electrocatalytic material and carbon dioxide. Mixed metal oxyhydroxide electrocatalytic materials such as nickel-iron oxyhydroxide may be formed. Also provided are the materials themselves, electrocatalytic systems comprising the materials, and methods of using the materials and systems.

Abstract: A water filter with alarm function for indicating blockage of a filter cartridge thereof and an alarm method are provided. The filter main body is provided with a filter cartridge and is arranged with a before-filtering water cavity. A filter upper cover covers the top of the filter main body. The before-filtering water cavity is accommodated with a floating-ball-type indicating apparatus, which comprises a floating ball, a connecting rod and a color scale. The connecting rod is mounted rotatably on an inner surface of the filter upper cover with the aid of a hinge support. The floating ball is arranged at the front end of the connecting rod. The color scale is also arranged on the connecting rod. A transparent visual cover that matches with the color scale is arranged on the upper surface of the filter upper cover.

Abstract: Systems and methods for treating contaminated impound water are disclosed which include a pretreatment stage wherein contaminated water is oxidized, pH adjusted, treated with a coagulant, and treated with a polymer to form a flocculent comprising bulk solids and fine particles. The oxidizing step may include two or more stages, one of which is a treatment with ferrous iron generated from iron filings or steel wool. Bulk solids are removed, and the liquid portion containing fine particles is applied to a low pressure microfiltration unit to remove the fine particles resulting in a microfilter effluent. The microfilter effluent may be directly fed to a reverse osmosis (R/O) unit. The R/O reject may be recycled to another R/O unit (second pass). The R/O permeate may be blended as needed with the microfiltration effluent to provide the final discharge effluent with reduced contaminant levels and maximized throughput.

Abstract: A method for applying an agricultural fertilizer to a field through an irrigation system connected to a source of hard water, includes providing a fertilizer composition comprising a mixture of (i) a fertilizer component comprising an ammonium phosphate or an ammonium sulfate, and (ii) an acid comprising one or more of a phosphoric acid, a citric acid, a malic acid, a formic acid, and an oxalic acid; combining the fertilizer composition with hard water from the hard water source and providing the mixture to an irrigation system; and using the irrigation system to apply the mixture of fertilizer composition and hard water to the field.

Abstract: Provided is a standalone integrated water treatment system for a distributed water supply including a filter input, a coagulation system in operative connection with the filter input, wherein the water is subjected to a coagulation process to create pin floc from suspensions in the water. A maturation buffer tank in operative connection with the coagulation system aggregates floc in size within the water. A spiral separator separates the water into two water streams, a first stream of water having most of the floc removed, and a second stream of water which includes a concentrated amount of the floc. An optional filtration system is configured to receive the first stream of water and perform a filtration operation thereon. A sterilization system is configured to perform a sterilization operation on the first stream of water. The water is then output from the sterilization system as potable water.

Abstract: A method and apparatus for the treatment of acidic surface water that has an initial pH and that contains one or more dissolved metals, the method including: (a) extracting a continuous stream of acidic surface water from an acidic surface water supply; (b) mixing a powdered neutralizing agent, having a particle size in the range of 8 micron to 500 micron, in the stream of acidic surface water to produce an alkaline slurry; and (c) dispersing the alkaline slurry for a dosing period over at least a portion of the acidic surface water supply to treat the acidic surface water supply; whereby the treatment of the acidic surface water supply will result in the pH of the acidic surface water supply increasing from its initial pH, and at least a portion of the one or more dissolved metals precipitating out of the acidic surface water supply to form a supernatant and a metal-rich precipitate.

Abstract: Disclosed herein is a controlled method of minimizing radioactive sludge generation in treatment of wastewater from an oil and/or gas well. The method comprises measuring a concentration of a radioactive material in wastewater to be treated and measuring a concentration of barium in the wastewater to be treated. The method further comprises adding a calculated quantity of sulfate to the wastewater to be treated sufficient to precipitate a quantity of barium sufficient to reduce the concentration of the radioactive material to a level such that sludge precipitated in a secondary precipitation has a radiation level below a defined radiation level.

Abstract: A process for removing sulfate includes combining a calcium compound and a fluid comprising sulfate to form a composition; adjusting the pH to be greater than or equal to 12; introducing, to the composition, an electrode comprising aluminum or a noble metal; contacting the composition with a material comprising aluminum if aluminum is absent from the electrode; applying a voltage to the electrode to oxidize the aluminum and to form aluminum ions; contacting the composition with the aluminum ions; and forming a precipitate to remove sulfate from the composition, the precipitate having a crystal structure including calcium, aluminum, and sulfate.

Abstract: Methods of removing one or more oxyanions from an aqueous fluid can comprise increasing the pH of an aqueous fluid containing one or more oxyanions and contacting the aqueous fluid with aluminum metal.

Abstract: The invention relates to a method for precipitating pentavalent calcium arsenate from an acidic solution, in which arsenic is at least partially in trivalent form. The acidic solution is neutralised before being routed to an arsenic oxidation stage,and a poorly soluble calcium-arsenic compound is precipitated from the solution, in which all the arsenic is pentavalent.

Abstract: The present disclosure is directed to the use of rare earth-containing additives, particularly rare earth-containing additives comprising rare earths of plural oxidation states, to remove, particularly from recreational waters, various target materials, such as disinfectant by-products and precursors thereof, phosphates, and organophosphates.

Abstract: The present invention provides reagents that may be useful for treating wastes such as impure aqueous materials including wastewater to remove a significant proportion of the heavy metals that may be contained therein. The reagents include a calcium aluminosilicate (CAS) source and may include one or more of the following elements as an oxide: calcium oxide, aluminum oxide, silicon oxide, iron oxide, magnesium oxide, sodium oxide, potassium oxide, and sulfate. Further, the reagent comprises lime either as CaO or Ca(OH)2. In addition, the invention provides methods for treating wastes such as impure aqueous materials to remove a significant proportion of the heavy metals contained therein.

Abstract: A method for purifying a water process stream whereby a precipitating agent is added to the water process stream to elevate the process stream pH to at least 10.5 to drop out precipitates which form separated solids comprising at least one of calcium precipitate, magnesium precipitate, barium precipitate, strontium precipitate, and silica precipitate. The separated solids are then coagulated and removed from the water process stream so as to yield a purified water process stream.

Abstract: A method and a device for purifying water from contaminant trace species, especially arsenic, by co-precipitating trace species during oxidation and precipitation of iron compounds with subsequent separation. The co-precipitation is improved by contacting the water with an iron-containing material prior to oxidation to increase the iron content of the water. Arsenic and other trace species harmful to health may be removed from water effectively and in a simple manner, thus being able to comply with the more restrictive limits of arsenic in drinking water.

Abstract: An electrolytic filtration system incorporating a filter vessel and an electrolytic element into a simple compact system which avoids the use of toxic chemicals and eliminates the need for large reservoirs to ensure adequate contact time to remove iron and other problem contaminants. The electrolytic filtration system includes a filter head having a control valve and an electrolytic generator. The control valve directs flow through the filter vessel and allows for an intermittent backwash cycle as desired. The electrolytic generator can be integrated into the filter head to provide ease of installation and reduce the overall footprint of the electrolytic filtration system. The electrolytic generator can include a flow sensor and power supply to provide for control of the electrolytic generator.

Abstract: A method of removing arsenic and heavy metals from water using metal salt hydroxide-gels is provided. The arsenic present in water is adsorbed onto the hydroxide-gels which can effectively be filtered through a diatomaceous earth (DE) filtration bed. The combination of DE mixed hydroxide-gels is also effective in removing arsenic from water and heavy metals from water.

Abstract: The invention provides methods for treating aqueous solutions to remove dissolved metallic ions.

Abstract: Novel devices for synthesizing ferrate and uses thereof are described. One aspect of the invention relates to devices and systems for synthesizing ferrate at a site proximal to the site of use.

Abstract: Reduced-carbon footprint concrete compositions, and methods for making and using the same, are provided. Aspects of the reduced-carbon footprint concrete compositions include CO2-sequestering carbonate compounds, which may be present in the hydraulic cement and/or aggregate components of the concrete. The reduced-carbon footprint concrete compositions find use in a variety of applications, including use in a variety of building materials and building applications.

Abstract: A reducing water purification material having a reducing iron-based precipitate selected from green rust, iron ferrite, reducing iron hydroxide, and a mixture thereof. A wastewater treatment process having steps of adding a reducing iron compound to wastewater, leading the wastewater to which the reducing iron compound is added to a reaction tank and forming a precipitate, separating the formed precipitate by a solid-liquid separation to obtain a sludge, and alkalinizing all or a portion of the separated sludge to form an alkaline sludge followed by returning to the reaction tank, wherein in the precipitation step, the wastewater to which the reducing iron compound is added and the alkaline sludge are mixed and are allowed to react in a non-oxidizing atmosphere under alkaline condition to form a reducing iron compound precipitate as the precipitate, thereby incorporating contaminants in the precipitate to remove the contaminants from the wastewater.

Abstract: The invention relates to a method of producing a coagulant product. It is characterized in that a starting material is prepared containing sludge resulting from the treatment of drinking water and an ore containing iron and/or aluminum, said starting material undergoing acid attack to form iron salts, aluminum salts or a mixture thereof. Application of said coagulant during implementation of a physico-chemical step of the treatment of waste water and/or industrial water.

Abstract: An indicator for the status of the filter is provided. The indicator comprises at least one erodable member in contact with the source fluid and a visual indication arrangement that permits a viewer to gauge the appearance of the erodable member to thereby gauge the filter status. The erodable member is eroded by interaction with the fluid or with an element within the fluid. The indicator may be incorporated as an integral component of a filter or may be a stand-alone device to be incorporated into a filter or filtration system.

Abstract: A rapid one-pass liquid filtration system efficiently concentrates biological particles that are suspended in liquid from a dilute feed suspension. A sample concentrate or retentate suspension is retained while eliminating the separated fluid in a separate flow stream. Suspended biological particles include such materials as proteins/toxins, viruses, DNA, and/or bacteria in the size range of approximately 0.001 micron to 20 microns diameter. Concentration of these particles is advantageous for detection of target particles in a dilute suspension, because concentrating them into a small volume makes them easier to detect. Additional concentration stages may be added in “cascade” fashion, in order to concentrate particles below the size cut of each preceding stage remaining in the separated fluid in a concentrated sample suspension. This process can also be used to create a “band-pass” concentration for concentration of a particular target size particle within a narrow range.

Abstract: The invention relates to using alcalophilic sulphate-reducing bacteria selected from at least one species of a Desulfohalobiaceae or Desulfonatronum species family or from species whose gene encoding for ribosomal PARN 16S has a homology equal to or greater than 97% with a corresponding gene of any species of the Desulfohalobiaceae or Desulfonatronum species family for producing a hydrogen sulphide substantially soluble in an aqueous medium.

Abstract: Novel devices for synthesizing ferrate and uses thereof are described. One aspect of the invention relates to devices and systems for synthesizing ferrate at a site proximal to the site of use.

Abstract: This invention relates to a method for desalination of seawater (5, 30) and separation of CO2 from exhaust (77) from a gas turbine (7). LNG (4) is fed into a heat exchanger (6) in which it receives heat from seawater (5) and heat from steam (27) from an exhaust boiler, and heat from combustion air (3) via a line to an air inlet (33) of said gas turbine (7), for evaporating LNG (4) to gas which is fed to a gas export module (10) and to a fuel gas skid (8) for supplying said gas turbine (7) with fuel. Thus said combustion air (3, 28) at the air inlet to said gas turbine (7) obtains a lowered temperature and increases an efficiency of said gas turbine (7). Said CO2-rich exhaust gas (77) from said gas turbine (7) is fed into a process unit (17) having an inlet (35a) with a fan (35b) and an outlet for CO2-reduced exhaust (13). Said cooled seawater from said heat exchanger (6) is fed into said process unit (17) via a coaxial feed pipe (67) for seawater and NH4OH arranged in said process unit (17).

Abstract: Presented is a liquid filtering apparatus and method that overcomes the disadvantages encountered with prior bed filtration systems by providing a filtering apparatus that incorporates a super-buoyant filter medium having a specific gravity very substantially lower than that of the process liquid being filtered. This feature enables a majority of the medium to float on top of the process liquid. Due to the significant differences in specific gravity between the media and the process liquid, super-buoyant media produce a highly advantageous means of naturally, gravimetrically separating both clean and contaminated filter media and process liquid into separate “phases”. Under normal filtering operation, the filter media is contained within a filter housing by a bed support near the top of the filter housing, and particulate material is filtered from a process liquid that passes through the housing.

Abstract: Methods for removing arsenic from water by addition of inexpensive and commonly available magnesium oxide, magnesium hydroxide, calcium oxide, or calcium hydroxide to the water. The hydroxide has a strong chemical affinity for arsenic and rapidly adsorbs arsenic, even in the presence of carbonate in the water. Simple and commercially available mechanical methods for removal of magnesium hydroxide particles with adsorbed arsenic from drinking water can be used, including filtration, dissolved air flotation, vortex separation, or centrifugal separation. A method for continuous removal of arsenic from water is provided. Also provided is a method for concentrating arsenic in a water sample to facilitate quantification of arsenic, by means of magnesium or calcium hydroxide adsorption.

Abstract: An improved water decontamination process comprising contacting water containing anionic contaminants with an enhanced coagulant to form an enhanced floc, which more efficiently binds anionic species (e.g., arsenate, arsenite, chromate, fluoride, selenate, and borate, and combinations thereof) predominantly through the formation of surface complexes. The enhanced coagulant comprises a trivalent metal cation coagulant (e.g., ferric chloride or aluminum sulfate) mixed with a divalent metal cation modifier (e.g., copper sulfate or zinc sulfate).

Abstract: A method for treating (in situ) large bodies of water contaminated with heavy metals and having varying density stratas to immobilize the contaminant metals is disclosed. The method, or process for (in situ) immobilization of metals is focused on treating large bodies of water having metals therein that are also adjacent a border of soil or earthen materials in an attempt to immobilize the metals from penetrating through the soil. The method is also able to treat the soil water boundary within the pit lake to provide additional immobilization. The pit lakes can include open pit lakes, subterranean mine lakes, flowing streams and the like. The method is also able to treat an abandoned mine prior to the filling of the mine with water. Initially, the density mean of the body of water is determined, which is densest typical at regions at or approaching 4 degrees C.

Abstract: An apparatus and method for removing phosphorus from a wastewater effluent stream from a hog waste lagoon. The wastewater effluent is introduced to the bottom of an inverted cone-shaped continuous crystallizer including a fluidized bed of struvite therein. An effective amount of ammonia is introduced to the wastewater effluent at the bottom of the crystallizer to elevate the pH of wastewater effluent a predetermined amount. An effective amount of magnesium is also introduced to the wastewater effluent at the bottom of the crystallizer. The composition adjusted wastewater effluent is then continuously passed upwardly through the fluidized bed of struvite to reduce the total phosphorus content of the wastewater effluent a predetermined amount of up to about 80% or more. The treated wastewater effluent stream is removed from the top of the crystallizer, and struvite crystals that grow large enough to sink from the bottom of the crystallizer are periodically removed from a collection chamber therebeneath.

Abstract: A method of purifying wastewater as a fluent coming either from industrial plants or from municipal sewage runs. The method includes the steps of running the wastewater as a fluent into a headworks where some preliminary treatment takes place. From there the fluent is passed into a primary reservoir. The primary reservoir analyzes the fluent as to certain control parameters such as pH, dissolved oxygen and/or dissolved solids. Thereafter the fluent flows into a primary reactor having a plurality of electrolytic cells therein. While in that reactor the fluent is subjected to electrical contacts which are located at the bottom and the top of the reactor. The effluent from the primary reactor passes through a ratio weir into a secondary receptor. The secondary receptor contains sensors for the measurement of control parameters such as pH, DO (dissolved oxygen TDS (total dissolved solids) and chlorine. Thereafter, the fluent is passed to a filtering device.

Abstract: A composition having a depot effect and a method for treating polluted waters and water sediments such that constituents that are hazardous to water are essentially decomposed or bound. Microbiological decomposition processes are long-term supported and water quality is improved without adding salt or decreasing the pH value. The composition contains one or more compounds which are produced by converting iron(III) nitrade and/or aluminium nitrade and hydrogen peroxide in the presence of a base and release oxygen and/or nitrations as oxygen donors in a prolonged manner when contacting water.

Abstract: A system is provided for removing dissolved metals from industrial wastewater by electrocoagulation. The system includes an electrocoagulation reactor with a DC power supply having an insulation support enclosure with positive and negative electrode plates disposed thereon. The electrode plates are insulated for each other but remain in direct contact with the wastewater as it flows between the electrodes. The DC power supply induces opposite charges on alternate electrodes thereby generating an electric field between adjacent electrodes to cause the electrodes to ionize and go into solution for interaction with the contaminants in the wastewater as it flows through the reactor. The reactor is housed in a pressure vessel container so the exterior pressure on the reactor is higher than its internal pressure preventing leakage of fluids and oxygen and hydrogen gases produced in the reactor by decomposition of water.

Abstract: A method of purifying sewage is described. The method relates to purifying sewage in sewage systems which comprise a toilet, by adding a precipitant for precipitation of phosphates and for binding organic substances. The method is characterized in that the precipitant is selected from the group consisting of iron salts and aluminum salts, such as sulphates, chlorides and nitrates and is adapted to be flushed with water in the toilet bowl when flushing. In the method, the sewage from the toilet is preferably conducted to a sludge separator through an outlet pipe which leads to the lower part of the sludge separator below its outlet.

Abstract: An in situ method and system for reductive dechlorination, the precipitation of chromium, the precipitation of heavy metals, and microbial denitrification. The invention comprises the formation of in situ anaerobic reactive zones to precipitate and filter out dissolved heavy metals as metallic sulfides, to degrade nitrate to nitrogen gas, to reduce chlorinated hydrocarbons to ethene, and to precipitate and filter out chromium. The invention is comprised of an injection well or wells that extend into a contaminated groundwater. A conduit located within the injection well conveys a reagent to the contaminated groundwater. The reagent may be a carbohydrate rich solution. Microbes digest the carbohydrates to produce sulfate reducing and methanogenic conditions within the reactive zone that include a dissolved oxygen level less than about 0.5 mg/l, a redox potential less than about −250 mv, and a dissolved organic carbon to contaminant ratio of greater than about 50:1.

Abstract: A method is taught for converting metal contaminants in the soil to less toxic forms as well as permitting their removal from groundwater. A first reactive solution comprising ferrous sulfate and an acid selected from the group consisting of sulfuric acid and phosphoric acid is injected to decomplex contaminants and precipitate them as insoluble compounds. A second reactive solution comprising hydrogen peroxide, and an acid selected from the group consisting of sulfuric acid and phosphoric acid is then injected to destroy organic liquids and enhance decomplexation. The pH of the first solution may range from 3 to 5, and the pH of the second solution range from 3 to 7, preferably 5 to 7. The process is particularly effective where chromium compounds such as hexavalent chromium are the contaminants.

Abstract: A method is providing for treating waters, such as standing and flowing waters and waste waters, soils, sediments and/or silts. At least one alkaline earth metal peroxide is brought into contact with such waters or the like, especially to effect immobilization of phosphates and heavy metals except manganese and iron therein.

Abstract: A system is provided for removing dissolved metals from industrial wastewater by electrocoagulation. The system includes an electrocoagulation reactor with a DC power supply having an insulation support enclosure with positive and negative electrode plates disposed thereon. The electrode plates are insulated for each other but remain in direct contact with the wastewater as it flows between the electrodes. The DC power supply induces opposite charges on alternate electrodes thereby generating an electric field between adjacent electrodes to cause the electrodes to ionize and go into solution for interaction with the contaminants in the wastewater as it flows through the reactor. The reactor is housed in a pressure vessel container so the exterior pressure on the reactor is higher than its internal pressure preventing leakage of fluids and oxygen and hydrogen gases produced in the reactor by decomposition of water.

Abstract: A process for removing dissolved uranium from water is provided. The process basically comprises (a) mixing phosphoric acid or particulate bone ash with the water, (b) mixing calcium hydroxide with the mixture produced in step (a) to thereby form calcium hydroxy phosphate or calcium hydroxy apatite which reacts with and complexes at least a portion of the uranium in the water to form a precipitate thereof, and (c) separating the precipitate from the water.

Abstract: Process for the treatment of polluted metal-mechanic industrial waste water and urban water, comprising: treating the polluted water with an acid liquor including ferrous chloride and hydrochloric acid, in order to promote the denaturalization of protein present in metal-mechanic industrial water or urban water and generate a clarifying and purifying flocculus from said polluted water.

Abstract: A method for removing accumulated metals from a cleaning solution is provided. After removal of the metals, the cleaning solution can be discharged or recycled. The process manipulates the pH levels of the solution as a means of precipitating solids. Preferably a dual phase separation at two different pH levels is utilized.

Abstract: Aqueous composition, including a water-soluble metal silicate complex which includes at least one divalent metal. A process for preparing an aqueous composition including water-soluble metal silicate complex includes combining monovalent cation silicate and divalent metal ions in an aqueous environment to form the water-soluble metal silicate complex. A process of modifying cellulose slurry includes adding an aqueous composition having water-soluble metal silicate complex which includes divalent metal to cellulose slurry. A process for preparing cellulose slurry includes adding monovalent cation silicate to cellulose slurry comprising a sufficient amount of divalent metal ions to combine with the monovalent cation silicate to form water-soluble metal silicate complex. A process of making cellulose product includes: adding an aqueous composition having water-soluble metal silicate complex including divalent metal to cellulose slurry; and forming cellulose product from the cellulose slurry.

Abstract: A method for treating in situ large bodies of water contaminated with heavy metals and having varying density stratas to immobilize the contaminant metals is disclosed. The method, or process for in situ immobilization of metals is focused on treating large bodies of water having metals therein that are also adjacent a border of soil or earthen materials in an attempt to immobilize the metals from penetrating through the soil. Initially, the density mean of the body of water is determined, which is densest typical at regions at or approaching 4 degrees C.

Abstract: An in situ method and system for reductive dechlorination, the precipitation of chromium, the precipitation of heavy metals, and microbial denitrification. The invention comprises the formation of in situ anaerobic reactive zones to precipitate and filter out dissolved heavy metals as metallic sulfides, to degrade nitrate to nitrogen gas, to reduce chlorinated hydrocarbons to ethene, and to precipitate and filter out chromium. The invention is comprised of an injection well or wells that extend into a contaminated groundwater. A conduit located within the injection well conveys carbohydrates and sulfates to the contaminated groundwater. Microbes digest the carbohydrates to produce sulfate reducing and methanogenic conditions within the reactive zone that include a dissolved oxygen level less than about 0.5 mg/l, a redox potential less than about −250 mv, and a dissolved organic carbon to contaminant ratio of greater than about 50:1.