Abstract: The invention discloses a process to implement and maintain water bodies larger than 15,000 m3 for recreational use, such as lakes or artificial lagoons, with excellent color, transparency and cleanness properties at low cost, which comprises the following steps: a.—providing a structure able to contain a large water body larger than 15,000 m3; b.—feeding the structure of step (a) with inlet water having iron and manganese levels lower than 1.5 ppm and turbidity lower than 5 NTU; c.—measuring water pH, ideally it should be within a range lower than 7.8; d.—adding an oxidizing agent to the water contained in the structure of step (a), with which a 600 mV minimal ORP is controlled in water for a minimal period of 4 hours and in maximal cycles of 48 hours; e.—adding a flocculating agent in concentrations within 0.

Abstract: Acidic metal-bearing wastewaters are treated to produce a finished water of sufficient purity to meet discharge standards while recovering metals removed in forms which are commercially valuable. The metals are selectively precipitated, either in a batch or in a continuous system, for removal of individual metal products in a specific sequence of steps from the wastewater. In each step, the pH is adjusted to the specific pH range and sulfide ion is introduced to precipitate the metals, excepting the removal of ferric iron and aluminum which is achieved using hydroxide precipitation. Bioconversion process using unique equipment converts sulfate in the wastewater to the hydrogen sulfide gas required for the precipitation process. This bioconversion process reduces the sulfate in the wastewater so that the water can be directly discharged or used for agricultural applications.

Abstract: The invention concerns a method for treating water for human consumption, so as to eliminate manganese and possibly other metals comprising steps which consist in: causing said water to pass at least over a bed of filtering material (3) consisting at least partly of manganese dioxide granules, said granules having a real density ranging between 3.5 and 4.5 and a hardness higher than 6 on the Mosh scale; regenerating, if necessary, said manganese dioxide, said regeneration being carried out mechanically.

Abstract: The present invention relates to the use of permanganate in the removal of heavy metal contaminants from heavy halide brines. In some embodiments, the present invention discloses methods of treating heavy halide brines that comprise providing a heavy halide brine that comprises a heavy metal contaminant, wherein the heavy metal contaminant comprises water-soluble ions; adding permanganate to the heavy halide brine; allowing a water-insoluble compound to form; and mixing the heavy brine and the water insoluble compound. In other embodiments, the present invention discloses methods of removing heavy metal contaminants from heavy halide brines.

Abstract: Iron particles for purifying soil or ground water of the present invention comprise a mixed phase of ?-Fe phase and Fe3O4 phase, and having a BET specific surface area of 5 to 60 m2/g, an Fe content of not less than 75% by weight based on the weight of the iron particles and a sulfur content of not less than 1,000 ppm. The iron particles are capable of decomposing or insolubilizing harmful substances such as organohalogen compounds and/or heavy metals, cyanogen, etc. contained in the soil or ground water in efficient, continuous and economical manners.

Abstract: An oxidation filtration system for cleaning groundwater, the system having an aeration tower and a filtration tank. Within the filtration tank is an upper chamber and a lower chamber. Contained within the lower chamber is a plurality of Styrofoam™ filter media. Separating the upper chamber from lower chamber is a filter media mash which keeps the filter media from entering into the upper chamber. The aerated water from the aeration tower enters into the base of the lower filter chamber and rises through the filter media into the upper filter chamber. As the water passes through the filter media, the dissolved solvents fallout of the groundwater and attach themselves to the Styrofoam™ media. An automated back flushing and clarifying process is also provided using a back flush port and a clarification port, a higher level water sensor in the aeration tower and a programmable logic controller.

Abstract: Compositions, methods and kits for purifying and clarifying and/or nutrifying contaminated drinking water and which comprise a primary coagulant material, a microbiocidal disinfectant and an oxidant system. Highly preferred compositions also contain one or more of a bridging flocculent material, the levels and ratios of coagulant to flocculent preferably falling within certain ranges, a cationic coagulant aid, especially chitosan, a water-soluble alkali, a water-insoluble silicate, and a food additive or nutrient source. The purified water remains free of discoloration for extended periods of storage.

Abstract: A method of reclaiming a well completion brine solution by using an organic chelant that is capable of discriminating between (i) iron and/or non-zinc heavy metals; and (ii) calcium and zinc.

Abstract: A method for treating a subsurface formation with a ferrous compound, to reduce a contaminant therein, involves introducing into the subsurface formation a ferrous compound in combination with sodium hydrosulfite in an amount sufficient to substantially prevent precipitation, during the introducing, of a major portion of the ferrous compound. The method was found to be useful in the reduction of hexavalent chromium to trivalent chromium at a Superfund site.

Abstract: A method of treating, in wastewater purification, sludge containing organic matter, divalent iron and phosphorus, in which the sludge that is treated is made to contain dissolved iron and phosphorus at a molar ratio Fe:P of above 1:1, the sludge is treated at 0–100° C. with an acid at a pH of 1–5 for dissolution of divalent iron and phosphorus from the sludge, the sludge is supplied with an oxidizer selected from hydrogen peroxide and percompounds, wherein divalent iron is oxidized by Fenton's reaction to trivalent iron, and (i) trivalent iron is precipitated as trivalent iron phosphate (ii) free radicals with a deodorization and sanitation effect are formed by Fenton's reaction, the sludge is then dewatered at a pH of at most 7, and the aqueous solution obtained in dewatering is recirculated to the wastewater purification.

Abstract: Mineral contaminants are removed from water in a system in which water is sprayed into an air head at the top of a tank through a diffuser and withdrawn through a pick-up tube. A solenoid valve operates to allows air from a compressor to flow into the top of the tank through a shuttle valve which is opened by the air pressure. Simultaneously a drain valve connected to the shuttle valve opens a drain, venting water and air from the tank. The shuttle valve, closed by the solenoid valve, closes the air supply line and connecting the shuttle valve to atmosphere, and pressure within the aeration tank can close the shuttle valve, which causes closing of the drain valve. The part of the valve which opens the drain is made responsive to excess pressure within the air tank to open the drain and so acts as a pressure relief valve.

Abstract: A cost-effective method for reducing the dissolved sulfide content in a wastewater stream and thereby hydrogen sulfide emissions therefrom involving the steps of adding a transition metal salt to the wastewater stream at the upper reaches of a wastewater collection system prior to at least some hydrogen sulfide volatilization followed by addition of an oxidant to the wastewater stream to generate elemental sulfur and a transition metal salt which subsequently participates in additional hydrogen sulfide capturing steps, thereby also improving water quality and wastewater treatment plant operations.

Abstract: A method of reclaiming a well completion brine solution by using an organic chelant that is capable of discriminating between (i) iron and non-zinc heavy metals; and (ii) calcium and zinc. The chelant contains a functional group selected from the group —CO2H or —PO(OH)R20 or a salt or ester thereof, —C(O)—, —OE, —SE, —N?C(R2)R3, EO—N?C(R2)R3, —N(R2)R3, and —N(C(O)R1)R2 group optionally substituted with a —COOH or —PO(OH)R20 or a salt or ester thereof, —SE or —OE group, wherein R2 and R3 are independently selected from E or forms, with nitrogen, phosphorous, oxygen or sulfur, a heterocyclic ring; E is R1 or —H; R1 is a C1–C30 alkyl or aralkyl group or a derivative thereof and R20 is —OH or R1.

Abstract: Iron particles for purifying soil or ground water of the present invention comprise a mixed phase of ?-Fe phase and Fe3O4 phase, and having a BET specific surface area of 5 to 60 m2/g, an Fe content of not less than 75% by weight based on the weight of the iron particles and a sulfur content of not less than 1,000 ppm. The iron particles are capable of decomposing or insolubilizing harmful substances such as organohalogen compounds and/or heavy metals, cyanogen, etc. contained in the soil or ground water in efficient, continuous and economical manners.

Abstract: A water treatment device capable of filtering out iron and manganese in raw water by oxidizing them and making them insoluble in water includes a raw water supply tube (4), one or more jet nozzles (5), each being at one end portion thereof in communication with the raw water supply tube (4) and having at the other end thereof a raw water jetting outlet for blowing out the raw water in a jet stream, one or more air introducing tubes (6) provided in correspondence to the jet nozzle or jet nozzles (5), each being at one end portion thereof opened to the atmosphere and being at the other end portion thereof opened to the inside of a corresponding one of the jet nozzles (5) upstream of the raw water jetting outlet and a filter container (3) containing a filter layer (2).

Abstract: This invention relates to a method for treating soybean refinery wastewater. More particularly, this invention relates to a method for treating soybean refinery wastewater with an aqueous iron salt solution to produce purified water. An aqueous iron salt solution is admixed with soybean refinery wastewater, the resulting mixture is agitated and passed through at least one filter device to form a filtered effluent, and the pH of the filtered effluent is adjusted to a value below about 8 to form purified water.

Abstract: A cost-effective method for reducing the dissolved sulfide content in a wastewater stream and thereby hydrogen sulfide emissions therefrom involving the steps of adding a transition metal salt to the wastewater stream at the upper reaches of a wastewater collection system prior to at least some hydrogen sulfide volatilization followed by addition of an oxidant to the wastewater stream to generate elemental sulfur and a transition metal salt which subsequently participates in additional hydrogen sulfide capturing steps, thereby also improving water quality and wastewater treatment plant operations.

Abstract: Disclosed herein is a process for removing odorants from a waste system comprising treating said waste system with ferric nitrate at a ratio of less than 2.4 parts nitrate oxygen for each 1 part reduced sulfur.

Abstract: A cost-effective method for reducing the dissolved sulfide content in a wastewater stream and thereby hydrogen sulfide emissions therefrom involving the steps of adding a transition metal salt to the wastewater stream at the upper reaches of a wastewater collection system prior to at least some hydrogen sulfide volatilization followed by addition of an oxidant to the wastewater stream to generate elemental sulfur and a transition metal salt which subsequently participates in additional hydrogen sulfide capturing steps, thereby also improving water quality and wastewater treatment plant operations.

Abstract: This invention relates to a method for treating acidic waste water, particularly mine effluent, and to a solid waste water treating material useful for the method. This waste water treating material is obtained by solidifying a mixture of rock wool and an inorganic binder mainly containing at least one kind selected from silicates, hydroxides and oxides of alkaline earth metals and alkali metals and has a porosity of 50% or more. When brought into contact with acidic waste water containing iron ions and sulfate ions, this waste treating material can not only neutralize the waste water but also remove harmful heavy metals such as iron and arsenic. Furthermore, it is easy to dispose the spent waste water treating material.

Abstract: The present invention is to provide a method for treating a wastewater containing heavy metals using a used iron oxide catalyst, which is to treat an acidic wastewater having a pH value of about 1.0 and containing Cu, Fe, Ni, Cr or Zn, the method including: adding the used iron oxide catalyst containing at least 70% magnetite (Fe3O4) to the wastewater at a weight ratio of 1:0.05; stirring the wastewater mixed with the iron oxide catalyst at a speed of 60 rpm for 15 minutes in a stirrer; and subjecting the wastewater to solid-liquid separation using a magnet for adsorption and removal of the heavy metals.

Abstract: The present invention is a method and system for treating iron-contaminated fluids. The system and method facilitates and uses an approach described herein as an activated iron sludge sequencing batch reactor (“AIS/SBR”) process. The AIS/SBR method oxidizes and removes ferrous iron as iron oxides from iron-contaminated fluids (such as mining-related discharge water, groundwater, surface water and industrial waste streams) and produces an effluent that is substantially devoid of iron and meets standards appropriate for natural discharge or further treatment. The AIS/SBR method of the present invention can be conducted in a single container assembly unit of the present invention, with time-controlled processing, to perform oxidation, precipitation and settling of iron from fluids. The method optionally includes the addition of alkaline material (e.g., limestone) when the initial liquid alkalinity (mg/L as CaCO3) to ferrous iron (mg/L) ratio of the fluid to be treated is less than approximately 1.7.

Abstract: Iron particles for purifying soil or ground water of the present invention comprise a mixed phase of &agr;-Fe phase and Fe3O4 phase, and having a BET specific surface area of 5 to 60 m2/g, an Fe content of not less than 75% by weight based on the weight of the iron particles and a sulfur content of not less than 1,000 ppm. The iron particles are capable of decomposing or insolubilizing harmful substances such as organohalogen compounds and/or heavy metals, cyanogen, etc. contained in the soil or ground water in efficient, continuous and economical manners.

Abstract: A product and method for the removal of pollutant heavy metals from aqueous solutions which precludes the end user from storing, handling, feeding and controlling hazardous soluble sulfide materials. The product is a slurry which includes a mixture of a liquid medium and an essentially insoluble salt wherein the salt is the reaction product of heavy metal ions, preferably selected from Mn++ ions, Fe++ ions, and Fe+++ ions, and sulfide ions derived from soluble sulfide sources such as sodium sulfide, hydrogen sulfide, and sodium hydrosulfide. Addition of the subject slurry to a wastewater stream will effect the precipitation of heavy metals with lesser equilibrium sulfide ion concentrations than that of the essentially insoluble salt. Solids collected by this method may be returned to subsequent wastewater streams for additional removal of heavy metals by any excess heavy metal sulfide salt.

Abstract: Processes for treating iron containing waste streams are provided. According to these processes, metal-containing compounds, particularly iron oxides are produced. These methods may, for example, be used in the processing of the waste streams from the chlorination of titanium-bearing raw materials and involve the use of certain combinations of neutralization and precipitation steps.

Abstract: An embodiment of the present invention relates to a biological process for continues purification of waste water by converting its constituents to a solid form that can be easily separated using retainable biological catalysts and a novel reactor hereafter referred to as “Reverse Fluidized Loop Reactor” (RFLR) for performing the above said process.

Abstract: A swimming pool water treatment system for removing iron from feed water, with the system including a large storage/reaction vessel to which a branch injection/filtration circuit is coupled. An alkali metal hypochlorite is injected into water flowing through the injection/filtration circuit and delivered to the storage/reaction vessel to permit precipitation of the iron oxide. A bank of parallelly coupled filters are provided in the branch filtration circuit upstream from the hypochlorite injection site for removal of insoluble iron precipitated from the treated water within the storage/reaction vessel. The branch injection/filtration circuit further incorporates an ozone injector valve where a flow of ozone is continuously introduced to water flowing through the branch injection/filtration circuit. The storage/reaction vessel is sized sufficiently large so as to permit an adequate contact dwell time for formation of the insoluble iron precipitate.

Abstract: A water treatment process for raw water containing dissolved Fe2+ and H+ cations to reduce the Fe2+ cation concentration therein involves oxidation of the Fe2cations to Fe3+ cations with the formation in the water of solid Fe(OH)3 from the Fe3+ cations. The process comprises the steps of oxygenating the water and raising the pH of the water. The oxidation of the Fe2+ cations and the fromation of the Fe(OH)3 are carried out in the presence of suspended particulate material in the water, the particulate material being present in the water at a concentration of at least 5 g/l.

Abstract: This invention discloses a cost-effective process for separating contaminants and a wide-range of fouling material from surface water, ground water and from industrial effluents. Having undergone effective pre-treatment, the water can be purified further by using high-surface area spirally wound micro-filtration (MF), ultra-filtration (UF), nano-filtration (NF) or reverse osmosis (RO) membranes. High-quality potable water free from pathogen and other contaminants is thus produced at low-cost from the pre-treated surface water and ground-water. Conversely, pre-treated industrial effluents are further purified at a relatively low-cost using NF or RO membranes, thus producing water suitable for recycle or surface discharge. The process of this invention uses cationic inorganic and/or polymeric flocculants to coagulate and flocculate the water-borne colloidal matter (e.g. clays, iron hydroxides, naturally occurring matter (NOM's), etc.

Abstract: A method for the manufacture of a ferric sulfate solution is provided, characterized in that, iron ore containing 30% by weight or more FeOOH as a trivalent iron (Fe3+) is calcined at 200-600° C., and then dissolved in sulfuric acid. A water treatment agent consisting of a basic ferric sulfate solution manufactured by the above mentioned manufacturing method is used as a coagulating agent for water treatment.

Abstract: Provided herein is a process for treatment of solutions which contain ferrous, ferric and soluble manganese species which process comprises addition of an oxidizing agent to such a solution to cause formation of manganese dioxide particles and adding manganese dioxide seed particles so as to cause nascent manganese dioxide agglomerates formed from the action of the addition of the oxidizing agent on the soluble manganese species to adhere to the manganese dioxide seed particles. By a process according to the invention, it is possible to effectively remove the soluble manganese species as solid manganese dioxide by having effective control over the size of the manganese dioxide particles to enable their subsequent removal using ordinary filtration techniques.

Abstract: A method for the removal of copper from waste waters includes providing a solution to be treated, the solution comprising copper; introducing a source of ferric ions and a source of ferrous ions into the solution; and adjusting the pH of the solution to promote formation of a copper-containing ferrite precipitate, whereby the solution is depleted in copper. In instances where the solution contains ferric ions, the method includes introducing a source of ferrous ions into the solution to obtain a solution comprising ferric ions and ferrous ions; and adjusting the pH of the solution to promote formation of a copper-containing ferrite precipitate, whereby the solution is depleted in copper.

Abstract: A method for treating sludge from wastewater purification is described. In the method, a sludge is treated, which contains phosphorus and at least one metal which originates from precipitation chemicals and which is selected among divalent iron and aluminum, the pH of the sludge being adjusted to below 4, preferably below 2, for dissolving the content of the phosphorus and said metal in the sludge; the remaining sludge is separated; the solution relieved of sludge and containing phosphorus and said metal is treated for precipitation of the phosphorus content of the solution as FePO4 at a pH of 2-3; and precipitated FePO4 is separated. The method is characterized in that the solution which remains after separation of FePO4 and which contains said metal from the precipitation chemicals, is recycled to the wastewater purification. The phosphorus content of the solution is precipitated as FePO4 by adding an at least equivalent amount of Fe3−.

Abstract: The present invention is directed to methods for purifying wastewater, including water which may or may not contain fatty acids or oils, by producing in situ a hydrophobic flocculant including a water-insoluble metal hydroxide. In the preferred methods, metallic cations are produced by the gradual dissolution of consumable, similar metal sources, preferably, a fluidized bed of metallic particles. The motion of the particles of the fluidized bed maintains the surfaces thereof clean of oxides and other contaminants in order to facilitate the gradual dissolution thereof. Oxidation of the dissolved cations to form the water-insoluble metal hydroxide is achieved by flowing an oxidizing agent, e.g., air or pure oxygen, through the system. Contaminants are entrapped and removed within the insoluble flocculants, including the water-insoluble metal hydroxide and, optionally, metallic soaps which are formed in the presence of fatty acids.

Abstract: A method to remove heavy metals concentrations in water down to very low levels is described. The method calls for the addition of a soluble sulfide to the water. This is followed adding a soluble iron reagent such as ferrous sulfate or ferrous chloride. The water is aerated. As an alternative to aeration, the pH of the water can be increased. Finally, the solids generated from the above steps are separated from the water. This method has been shown to remove heavy metals, particularly copper and zinc, from actual industrial wastewater to very low concentrations, i.e., below about 100 ppb. Furthermore, the treated water is free of sulfide. The byproduct sludge comprises iron sulfide, iron oxides, iron hydroxides, and the heavy metal sulfides.

Abstract: Apparatus and methods for material separation consisting of a cyclone aerator which can enhance contact between contaminated water and air, or a oxidant gas, and can enhance the contact and attachment between particulates contained in the suspension and bubbles formed in the cyclone aerator. One embodiment comprises a plurality of plates positioned in a spaced relationship to one another within a jacketed tube. The plates are arranged in a distinct, non-radial orientation extending partially towards the center of the jacketing tube to define a cylindrical chamber within a center of the plates and an annular cylindrical chamber between the plates and the jacketing tube. A suspension is introduced into the cylindrical chamber tangentially through a feed line proximate or integral with a jacketing tube top of said jacketing tube to develop a swirling flow pattern of the suspension within the cylindrical chamber.

Abstract: A method for recovering at least one metal from an acidified waste water sludge by liquid-liquid extraction by providing an acidified waste water sludge containing ions of at least one metal and organic material, treating the waste water with an oxidizer to convert the organic material into a form that does not have an unfavorable effect on a subsequent liquid-liquid extraction, and subjecting the treated, acidified waste water sludge to a liquid-liquid extraction thereby obtaining an organic phase loaded with ions of said at least one metal, and subsequently recovering ions of said at least one metal from said organic phase.

Abstract: Aluminum particles are reacted with heavy metal ions in a first acidic aqueous solution to form heavy metallic particles that are suitable for recycling and reuse when recovered from the first aqueous solution. The first residual aqueous solution may also contains ferrous ions obtained by acid redissolving a co-precipitated heavy metal hydroxide and ferrous hydroxide sludge that is produced in the treatment of a dilute chelated heavy metal solution. The first residual aqueous solution with heavy metals substantially removed is recycled and reused as the ferrous reagent for treating said dilute chelated heavy metal bearing solution. The process disclosed herein is useful for treating both dilute and concentrated wastes and wastewaters generated by industries such as metal plating and metal etching and printed circuit board fabrication.

Abstract: A method and system is provided for producing a commercially usable iron oxide material by treating iron contaminated water. A clean effluent is also produced. Iron contaminated water is sampled to determine a bicarbonate to iron molar ratio. The flow of the water is directed to a collection basin assembly when the bicarbonate to iron molar ratio is at least 2 to 1. Iron oxide material precipitates in the collection basin assembly. The water from the collection basin assembly is directed to a constructed wetland. After a period of time, the iron oxide material in the collection basin assembly can be harvested and used for commercial purposes without excessive further treatment.

Abstract: Nuisance concentrations of hydrogen sulfide and other malodorous compounds are controlled in liquid and sludge waste systems by adding alkaline iron. The process removes immediate sulfide and suppresses the formation of further nuisance sulfide with a single application. As the sulfide and other malodors are being mitigated in this process, alkalinity is added to the waste as a reaction by-product, which acts to increase the waste pH, decreasing corrosivity and promoting biological treatability and purification of the waste.

Abstract: The invention relates to a method for treating waste water sludge comprising at least one metal originating from a waste water treatment coagulant, and phosphorus and heavy metals in order to recover said at least one metal and phosphorus and to discharge said heavy metals. In this method said waste water sludge is acidified to dissolve metals contained in the sludge thereby yielding an acidified sludge solution containing at least 1% by weight of at least one metal to be recovered. In a first precipitation stage the pH of said acidified sludge solution is raised to precipitate at least one metal to be recovered as a phosphate, and thereafter the phosphate precipitate is separated, thereby leaving a solution comprising heavy metals. In a second precipitation stage the pH of said solution comprising heavy metals is raised and, if necessary, an appropriate chemical is added to precipitate heavy metals, and thereafter the precipitate is discharged.

Abstract: This is a method of treatment of materials with the use of a sacrificial metal and reducible ions which comprises steps ofa) contacting the material to be treated with the surface of the said sacrificial metal, wherein the said material to be treated is included in an aqueous solution or emulsion or suspension; andb) inducing treatment processes at the surface of the said sacrificial metal by providing said reducible ions included in an electrolyte, wherein the said reducible ions react with the said sacrificial metal to form oxidation-reduction products comprising dissolved or suspended reduced species and dissolved or suspended species from oxidizing the said sacrificial metal.The method can be used for treatment of water, groundwater, including in-situ, wastewater, polluted gases, solid waste, and other materials.

Abstract: A recycling apparatus which preferably treats used antifreeze/coolant in four cycles is disclosed. The recycling apparatus includes a number of tanks for storing the antifreeze/coolant during the various treatment cycles, a number of containers for storing chemical reagents used to chemically treat the antifreeze/coolant and a number of filters used to capture impurities suspended in the treated antifreeze/coolant. During a fill cycle, the used antifreeze/coolant is introduced into a treatment tank and the concentration of the antifreeze/coolant is adjusted, if necessary, to a predefined range. During a mix cycle, the used antifreeze/coolant is mixed with various reagents to adjust the pH value, as well as to coagulate and flocculate the impurities. A reverse mixing and aspiration of the antifreeze/coolant in the tank during the mix cycle ensure that the reagents will mix well and react with the impurities in the used antifreeze/coolant to form a sludge.

Abstract: A water aeration system for receiving gas and/or iron laden water from a water source and delivering purified water to a service line. The system includes a tank with an internal volume fillable with water, a tank inlet, a tank outlet, and an aerator. Water is introduced into the tank through the tank inlet and passes downwardly within the tank. The downwardly moving water encounters a counterflow of upwardly migrating bubbles introduced into the tank by the aerator, and the air bubbles cause impurities in the water to precipitate out and settle onto the floor of the tank and gases to the vented to atmosphere. After moving to the bottom portion of the internal volume of the tank, the water passes upwardly through an upstanding water outlet pipe located within the tank internal volume and passes through the tank outlet to be removed from the tank. The system may also include a mechanism for flushing from the tank precipitates collected on the tank floor.

Abstract: Waste water sludge which contains phosphorous, heavy metals and at least one metal originating from a waste water treatment coagulant, is treated in order to recover the phosphorous and the at least one metal, and to discharge the heavy metals. The at least one metal includes iron.

Abstract: A method and a plant for regenerating zinc sulfate electrolyte in steel strip electrogalvanizing processes by precipitating dissolved iron from electrolyte circulating through a coating cell. A partial quantity of the circulating electrolyte to be regenerated is removed from the coating cell and the dissolved iron is oxidized to Fe.sup.3+ by a redox-controlled addition of oxidizing agents. Subsequently, by raising the pH value to the precipitation limit of Fe.sup.3+ by a controlled addition of a ZnO/water suspension or a ZnCO.sub.3 /water suspension, the dissolved iron is precipitated as sludge. Any excess ZnO or ZnCO.sub.3 is then dissolved by adding fresh electrolyte. The precipitated iron sludge is conducted through a suitable filter such as a filter press, a filter belt, a decanter, etc., and the precipitated iron is filtered out in this manner. Subsequently, the purified partial quantity of the electrolyte is returned to the coating cell.

Abstract: Embodiments of an apparatus and method for ferrite formation and the removal of heavy metal ions by ferrite co-precipitation from an aqueous solution at ambient temperature have been developed. Magnetically susceptible ferrite crystals can be continuously formed from aqueous solution and the heavy metal ion solution can be continuously treated by the ferrite co-precipitation process. The heavy metal ions are incorporated into the lattice points of the spinel ferrite structures. The precipitates of ferrite materials can then be magnetically separated. The main apparatus includes a ferrous sulfate mixing tank with a feeder assembly; a reaction tank or, alternatively, neutralization and oxidation tanks; settling and polishing tanks; and a magnetic separator. The reaction tank or oxidation tank includes an air distributor; a pH controller; and promoter feeding and ferrite product recirculating systems.

Abstract: A method and the apparatus (hereinafter referred to as the environmental monitoring system or EMS") designed to sample, detect, measure, and report, in real time, the presence of contaminants and thereby provide users with the ability to continually monitor conformance of water with established health and safety standards. When integrated with a user operated process control system, the EMS enables users to control the monitored process and to thereby ensure that the sampled water complies with established health and safety standards.

Abstract: A method and apparatus facilitate removal of metals from acidic liquids containing dissolved metals (such as pulp mill bleach plant washer filtrate) by oxidizing the liquid with ozone, hydrogen peroxide, oxygen, and/or air to increase the valence of the metals (like Mn and Fe) so that they become easier to precipitate. Oxidation may be practiced using any suitable reactor, such as a gas-contact reactor, or a plunger type reactor where the oxidizing agent is primarily gaseous, or a static mixer or stirred tank where the oxidizing agent is primarily liquid. After oxidation the pH of the liquid is adjusted (e.g. to over 6, preferably about 8-11) to precipitate the metals. The precipitated metals are then removed by filtration, sedimentation or flotation, and the metals-depleted liquid used elsewhere in the pulp mill.

Abstract: A method for the removal of metal from a metal-containing aqueous medium wherein the aqueous medium is passed through a particulate carrier material in the presence or ferrous iron and an oxidant and at such velocity and in such direction that the carrier material particles are fluidised in the aqueous medium and wherein metal-containing coatings are formed on the surfaces of the carrier material particles and wherein the particles thus coated are separated from the aqueous medium. A method for the production of iron oxyhydroxide-containing adsorbent wherein the carrier material particles are fluidised in an aqueous medium in the presence ferrous iron and an oxidant so as to form iron oxyhydroxide coatings on the particles and wherein the particles thus formed are separated from the aqueous medium.