Abstract: A method for recovering metals from solutions is described. A particular embodiment of the method concerns recovering copper metal from aqueous solutions containing copper ions, such as ammoniacal circuit-board etching solutions. A working embodiment of the invention comprises first treating a solution containing copper ions with a sufficient amount of an acid to obtain a solution pH of from about 1 to less than about 2.5. A reducing metal, such as iron, is then added to the solution to precipitate metal ions as metals. The reducing metal has a mesh size of about 230 or greater. The metal precipitate is recovered from the solution. The method is generally sufficiently efficient to allow discharge of solutions treated according to the method of the invention into public waste waters wherein the solution has less than about 5 ppm, and preferably less than 2 ppm, metal ions.

Abstract: A waste water treatment system is illustrated which can be configured to be portable and which minimizes the addition of solids to be disposed of through the use of ozone for contaminant reduction to basic elements after the pH value of the waste water to be treated is properly adjusted. This ozone in one stage is combined with ultrasound to cause coagulation and precipitation. In another stage, ozone and ultraviolet light are used in a reduction process. Ion alignment using a magnetic field and an electrochemical flocculation process to which the waste water is subjected causes further coagulation and precipitation. As designed, the system can operate continuously with redundancy at appropriate points so that removal of solids from the filtration units can occur simultaneous with the overall decontamination process.

Abstract: For the removal of heavy metal contaminants from industrial waste water, a method is proposed for preparing a dense precipitate having superior handling and disposal properties. The method comprises incremental adjustment of the pH to maintain a low saturation ratio and recycling of slurry to provide seed crystals for secondary nucleation.

Abstract: A multistage treatment system for treating nutrient-rich water containing nitrogen compounds, phosphorous compounds, and other minerals. Three or more vessels or stages typically constitute the multistage treatment system. Each stage of the system is a reaction vessel having a first zone containing a substantially insoluble salt for precipitating phosphorous compounds and other minerals, a second zone containing a microorganism retained on an inert substrate for converting nitrogen compounds, and a separation device for removing precipitates from the water. The effluent from the multistage system may be further treated in ponds cultivated with aquatic grass or in a packaged algae filter having a medium for supporting algae growth and an artificial light source.

Abstract: A process for treating acid wastewater containing heavy metals has been invented, the process including adding fly ash to the acid wastewater to reduce heavy metals content of the acid wastewater. In one aspect the acid wastewater contains soluble iron and adding fly ash reduces the level of soluble iron. In one aspect the acid wastewater contains sulfate ions and adding fly ash reduces the sulfate ion level. In one aspect solid silicate salts are added to the acid wastewater. Preferably undesirable very hydrous iron hydroxide precipitate is not formed. In certain aspects the pH of the acid wastewater is raised to an environmentally acceptable level. In one aspect the process is a batch process. In another aspect the process is a continuous process.

Abstract: Hydrophobic organic substances are separated from aqueous industrial effluent containing said hydrophobic organic substances and hydrophilic organic substances by adding to the effluent at substantially neutral pH a salt of a metal having an insoluble hydroxide thereby forming an hydroxide sludge entraining said hydrophobic, oxidizable organic substances, and separating the sludge from the treated effluent containing the hydrophilic organic substances. The invention has particular application to the removal of toxic hydrophobic, oxidizable organic substances from aqueous industrial effluent and their subsequent destruction by oxidation, especially ozonation, of the separated sludge, thereby reducing the oxygen demand compared with oxidation of the entire effluent to reduce said toxic substances to their discharge consent level.

Abstract: Impure liquid media containing contaminating amounts of metallic impurities, e.g., alkaline earth metals, heavy metals and/or radioactive elements, for example industrial effluents from the nitric acidulation of rare earth concentrates, are purified by separately introducing a source of phosphorus and a source of barium into the impure medium, whereby precipitating a solid residue which comprises a barium phosphate having such contaminating metallic impurities distributed therein, and thence separating the solid residue from the liquid medium thus purified.

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: Digestion liquor is used in the paper pulping process to dissolve lignins and free the cellulose fiber from raw wood chips. After pulping, spent digestion liquor is laden with lignins. Heretofore, it was known that lignins could be coagulated by acidification of the digestion liquor, but such method coagulated the lignins in a slimy gelatinous mass that was difficult to separate from the liquor. It has been discovered that the addition of water soluble, surface active, polymeric agents to the digestion liquor prior to acidification, results in an easily separable lignin coagulant after acidification.

Abstract: A method for treating a chelate bearing waste solution employs a two-step process which includes elevating the pH of the solution to a pH greater than 10 and precipitating the metal as the hydroxide out of solution, followed by treating the resultant solution with an oxidant to destroy any remaining free chelate.

Abstract: The present invention relates to a process for the elimination of heavy metals from a closed white water system within the pulp and paper industry, wherein one adjusts the pH of the white water to between 5 and 11, and that one subsequently precipitates the resins present using a flocculation agent, whereby by a simultaneous elimination of the heavy metals is obtained.

Abstract: A powdered composition for treating spent dry film stripping and/or developing solutions comprising: 10 to 70 percent by weight of an aluminum source, such as aluminum sulfate, aluminum chloride; and 28 to 90 percent by weight of siliceous particulates, such as diatomaceous earth, sodium potassium aluminum silicate or expanded perlite. The powdered composition may also include 3 to 35 percent by weight of a metal precipitation agent, such as trimercapto-s-triazine, sodium dimethyldithiocarbamate, starch xanthate, sodium diethydithiocarbamate and thio red, to precipitate the metal from the spent solutions and/or 0 to 10 percent by weight of a dust-suppression agent such as water or propylene glycol. A method of using the disclosed compositions is also revealed in this application.

Abstract: A sewage purification method which includes a first step in which at least two kinds of flocculants are introduced in sewage for stirring and mixing therewith so as to float and settle inorganic and organic materials. The first step is sequentially repeated more than one time. Next, at least three kinds of flocculants are introduced into the supernatant obtained in the first step for stirring and mixing therewith so as to further float and settle remaining inorganic and organic materials. At least one of the first and second steps is sequentially repeated more than one time. In the above way, middle water, drinking water and super-pure water can be obtained from sewage. Purification of exhaust gas is also possible by introducing such exhaust gas in one of the above steps.

Abstract: A process for dye removal from effluent is disclosed which includes treating the effluent with a reducing agent, adjusting the pH to a selected value in the range of 2-7, treating the effluent with a particular charge neutralization mixture, adjusting the pH a second time and subjecting the mixture to a flocculating process with selected chemicals.

Abstract: A steam stripping method for the softening of a feedstream of water including the steps of passing the feedstream of water into intimate contact with uncondensed steam such that the steam elevates the temperature of the feedstream of water, increasing the pH of the feedstream of water, reacting the feedstream of water with the steam so as to produce uncondensed steam byproducts and liquid byproducts, and passing the liquid byproducts through a filter so as to remove solids from the liquid byproducts. The steam is reacted with the feedstream of water at a rate of one pound of steam per ten pounds of feedstream water. A quantity of magnesium hydroxide can be added to the feedstream of water so as to initiate silica crystal formation. The liquid byproducts can pass through a bed of aluminum prior to the step of passing through a filter so as to reduce a silica content of the liquid byproducts.

Abstract: The invention is concerned with clarifying contaminated liquids and, in one described embodiment, contaminated liquid is continuously supplied to a first vessel, a first treatment material is intimately mixed into the contaminated liquid in the first vessel, the contaminated liquid/first treatment mixture is passed to a second vessel and a second treatment material is added to the contaminated liquid and first material mixture and intimately mixed therewith.The first treatment material preferably comprises one or more compound of the group including soluble magnesium salts, ferrous salts, manganous compounds and cuprous compounds and the second material is an alkali intended to reduce the pH of the final mixture.After the second treatment material has been added the impurities separated out from the final mixture are extracted from one outlet from the second vessel and clarified liquid is discharges from another outlet of the second vessel.

Abstract: A process for reducing the phosphate content in waste water from the preparation of salts of ascorbic acid 2-monophosphate comprisesA. treating the waste water from the crystallization of the metal salts of ascorbic acid 2-monophosphate with an alkali metal or alkaline earth metal hypochlorite, chlorine or H.sub.2 O.sub.2,andB. precipitating, at a pH of 9-12, the inorganic phosphate which has been produced from organically bound phosphorus and/or was present in the waste water, especially as calcium phosphate.

Abstract: An apparatus for waste water treatment, wherein fluorine contained in waste water is treated into a fluoride through a chemical reaction and sludge containing the fluoride is thickened and dehydrated into a sludge cake, has first and second tanks each packed with calcium carbonate mineral. In the first tank, waster water containing fluorine is agitated by air discharged from an air diffuser and caused to react with the calcium carbonate mineral. Through this reaction of the waste water with the calcium carbonate mineral and action of microorganisms on the surface of the calcium carbonate mineral, a pH value and a fluorine concentration of the waste water is adjusted till the pH value and the fluorine concentration fall within their respective predetermined ranges.

Abstract: Arsenic and TOC are removed from drinking water or wastewaters by use of finely-divided metallic iron in the presence of powdered elemental sulfur or other sulfur compounds such as manganese sulfide, followed by an oxidation step. A premix may be produced for this process, by adding the iron, sulfur and oxidizing agent to water in a predetermined pH range. The iron and sulfur are mixed for a period of time dependent upon the temperature and pH of the water and the presence of complexing or sequestering minerals and organic acids in the water. An oxidizing agent is added to the mixture and agitating is continued. In a preferred embodiment the oxidizing agent is hydrogen peroxide. Water is decanted from the mixture after a sufficient reaction time, to produce a concentrated premix. This premix can be added to water intended for drinking or to industrial effluents containing toxic materials.

Abstract: A method for treating mine water from an underground trona ore mine comprising pumping the mine water from the mine, introducing caustic soda into the mine water, maintaining the pH of the treated mine water to between about 11.5 and about 14, separating the treated mine water and introducing the treated mine water into an alkali production process.

Abstract: A change-over apparatus for use in conjunction with a cooling system of an internal combustion engine having an engine and radiator and having an upper hose between the radiator and the engine which has been cut to form an upper radiator hose section and an upper engine hose section wherein a change-over apparatus comprising at least one tubular body having first and second tube bodies having end openings, with the end opening for connection to said upper radiator hose section, said second end opening for connection to said upper engine hose section, a liquid ingress opening spaced from said first end opening, a liquid egress opening spaced from said second end opening, and, optionally, a flow regulating means placed between said liquid ingress opening and said liquid egress opening.

Abstract: A process and apparatus are described for clarifying milkhouse wastewater, which is rich in phosphorus and also contains colloidal and suspended solids. This wastewater is obtained during the washing of milk pipelines of a dairy milking system. The wastewater is collected in a treatment vessel, with the ratio of suspended solids to phosphorus in the wastewater being lowered either before entering or while in the treatment vessel. To this wastewater of lowered suspended solids:phosphorus ratio, there is added sufficient calcium, preferably in the form of lime, to react with all of the phosphorus in the wastewater to form calcium hydroxyapatite precipitate. It has been discovered that, by lowering the ratio of suspended solids:phosphorus, sufficient calcium hydroxyapatite precipitate is formed to sweep with it during settling substantially all colloidal and suspended solids thereby leaving a clear, environmentally safe effluent water.

Abstract: A method and apparatus for forming a slurry of metal oxide in a mineral or the like (e.g. of magnesium or calcium oxide) and introducing the slurry to an acid neutralization process in a time period before substantial hydration of the oxide has occurred.

Abstract: Methods for purifying aqueous waste streams containing a water reducible paint composition and equipment systems capable of conducting such methods are provided. In general terms the methods can be practiced by first providing an aqueous waste stream comprising a minor amount of a water reducible paint composition. This aqueous waste stream will commonly have a water content of at least 95 percent by weight. An acid, preferably sulfuric acid, is then admixed with the aqueous waste stream to form a suspension comprising water and precipitated paint compounds. Following the precipitation step a portion of the precipitated paint compounds are separated from the water.

Abstract: Objectionable byproduct aqueous effluents containing contaminating amounts of hydroxynitroaromatic compounds, in particular those aqueous effluents produced during the synthesis of nitroaromatic compounds, e.g., dinitrotoluenes, via reaction of an aromatic compound with nitric acid in the presence of sulfuric acid, are efficiently, facilely and economically treated/removed by (a) intimately contacting a mixture of at least one nitroaromatic compound and at least one hydroxynitroaromatic compound with an aqueous wash medium containing a neutralizing agent, (b) separating the resulting admixture into an organic phase and an aqueous phase, (c) recycling a fraction of the separated aqueous phase to the aqueous wash medium to thus constitute a portion thereof, and (d) periodically draining a fraction of the wash medium, whether to destruction thereof or to waste.

Abstract: A process for treatment of hazardous liquid waste comprising trace amounts of hazardous elements in solution as oxyanions by oxyanion fixation within ettringite and related minerals. In accordance with the disclosed process, reagents for forming ettringites are mixed with the waste stream resulting in the formation of oxyanion-substituted ettringite and related materials. The resulting ettringite and related minerals are separated by filtration from the liquid. Thereafter, the liquid, having an elevated pH, is neutralized by carbon dioxide sparging resulting in precipitation of excess reagents in the liquid. Thereafter, the precipitates are filtered, producing a clean liquid.

Abstract: A method of laundering oily items comprises laundering said items in a wash solution which includes a surfactant system and a source of alkalinity. The source of alkalinity is an alkali metal aluminate preferably sodium aluminate at a concentration effective to have at least about 25 ppm of the alkali aluminate present in the wash solution measured as alumina. The wash solution is then separated from the laundered items and its pH reduced to about 9 or less. A destabilizing polymer such as diallyldimethyl ammonium chloride can be added. This combination causes the oil and grease to separate from the wash solution and float to the surface along with the sodium aluminate. If the concentration of the sodium aluminate is above about 100 ppm preferably about 250 ppm, there is no need to add the destabilizing polymer. This does not affect the overall efficiency of the detergent, yet significantly improves the ability to separate the oil and grease from the waste wash solution.

Abstract: Potassium permanganate is added to paper mill wastewater streams at an elevated temperature to remove color compounds from the effluent streams. The potassium permanganate causes the formation of flocculant particles which are precipitated out of the stream. This precipitate is then treated with acid to cause resolubilization.

Abstract: A method for treating the waste stream resulting from electroless plating operations such as copper electroless plating. The waste stream is simultaneously treated with hydrogen peroxide and UV light to bring the level of contaminants below the discharge limit. In one embodiment, the waste stream is also diluted with rinse water from the plating process.

Abstract: Process for treating aqueous media containing metal ions having valences of +2 and higher and optionally acid comprising:(a) contacting the aqueous media, at a pH of about 1-5, with an effective amount of product recycled from step (b) to dissolve at least some metal carbonates, produce at least some CO.sub.2, convert at least some metal ions having a valence of at least +3 to metal hydroxide precipitates, and neutralize some acid, if present;(b) contacting the product of step (a), at a pH of about 4-8.5, with an effective amount of Na.sub.2 CO.sub.3 to convert at least some metal ions of +2 valence to metal carbonate precipitates and form at least some dissolved sodium salts;(c) recovering, from a portion of the product from step (b) that is not recycled, metal carbonates, metal hydroxides, and sodium salts.

Abstract: The removal of bleaching chemical-consuming metals from treatment fluids in a cellulose pulp mill is facilitated by treating the pulp in an acidic or neutral stage to dissolve metals, washing or thickening the pulp to produce a filtrate containing dissolved metals, and then using an alkali liquid to adjust the pH of the filtrate to cause dissolved metals to precipitate. The alkali liquid is pretreated with carbon dioxide to reduce the sulfide content and increase the carbonate content thereof, preferred alkali liquids being green liquor and white liquor. The reduced-metal content filtrate is used in the bleach plant of the pulp mill, to make bleaching chemicals, as a wash liquid, etc. Treatment of the alkali liquid with carbon dioxide is typically practiced by scrubbing the liquor with carbon dioxide gas, for example, using a plate column scrubber or a stationary packing scrubber.

Abstract: The process relates to the treatment of aqueous solutions of polyhydric alcohols to remove heavy metal components, oils, organic contaminants and, optionally, water. The process is particularly well suited for use in the treatment of spent antifreeze/coolant from the cooling systems of internal combustion engines.

Abstract: Metals contained in various wastewaters are selectively recovered as metal precipitates and/or as spinel ferrite and water suitable for discharge into the environment is obtained. High grade magnetic spinel ferrite is recovered from wastewaters having aluminum and arsenic if present in the wastewater, removed from the wastewater. There are three process stages for the treatment of wastewater. In the first process stage which is optional, at least a portion of at least one non-ferrous or non-ferric metal is precipitated from the wastewater by subjecting the wastewater to an oxidizing agent to increase the oxidation-reduction potential of the water, by adjusting the pH of the wastewater to a pH at which the metal precipitates from the water and by adding an organic or inorganic sulfur compound, capable of causing the metal to form a precipitate, to the water in a quantity sufficient to precipitate the metal.

Abstract: Materials and methods relating to water treatment processes are described. More specifically, the process is non-toxic and is useful for the removal of algae, other suspended solids, or contaminants in surface waters or in potable water treatment. Coccolithic calcium carbonate can be used in combination with a flocculent such as aluminum chloride to obtain the desired results.

Abstract: The object of the present invention is reuse of the filtrate of a paint mist-cleaning water mixture as cleaning water without reduction in concentration efficiency. According to the present invention, a waste paint-cleaning water mixture 2 available on trapping a water-based paint mist in cleaning water 1 is concentrated to recover the paint and the aqueous phase is recycled as cleaning water. In this system, the cleaning water prepared by reusing the aqueous phase is adjusted to an acid value of not greater than 10 and a pH value of 7.0 to 9.0. Controlling the amount of low molecular acid components in the aqueous phase in this manner prevents an abnormal viscosity increase in the filtration-concentration of the waste paint-cleaning water mixture.

Abstract: A method and apparatus for controlling the pH of a water stream using carbon dioxide, in which carbon dioxide at a selected pressure and flow rate is mixed with a carrier water, also at a selected pressure and flow rate, and the carbon dioxide-carrier water mixture is injected into the water stream, which is at a lower pressure, thus allowing the carbon dioxide to come out of the solution, contact the water stream and correspondingly adjust the pH of the water stream.

Abstract: A method for treating effluent seawater used in a process for desulfurizing flue gas includes aerating the effluent seawater in an aeration pond. The aerated effluent seawater is then channeled through a bed of crushed limestone for raising the pH of the seawater to at least 7.8. The seawater is then channeled back to the fresh seawater source, such as an ocean, without causing any harm to the environment. Fresh limestone is periodically added to the bed and the size of the bed is varied depending on the amount of effluent seawater to be treated.

Abstract: A treatment solution which is stored in a treatment vessel is supplied to a mixing vessel and a simple fluoride solution is supplied into the mixing vessel from a simple fluoride supply vessel to convert aluminum salt of complex hydrofluoric acid which is contained in the treatment solution to complex hydrofluoric acid. Concentration of HF remaining in the mixed solution is measured with a metal silicon electrode meter provided in an HF concentration measuring part, so that a control signal is transmitted from a control unit to a pump and a flow control part on the basis of the data as obtained. The simple fluoride solution is supplied from the simple fluoride supply vessel to the treatment solution which is stored in the treatment vessel to return the activity of the treatment solution stored in the treatment vessel and to control the same in a prescribed range.

Abstract: The present invention in one embodiment, is a process that uses a chemical treatment to remove arsenic, organic acids, and heavy metals from antifreeze solutions. In one aspect such a method includes adding an iron salt, to an antifreeze solution containing arsenic and heavy metals with adequate mixing for dispersion throughout the solution. Then, a base is added to increase the pH to a level from about 8 to 10. As the base is added, a precipitate forms and is then removed by standard filtration techniques. The arsenic, organic acids, and heavy metals co-precipitate with the iron and are removed by filtration. The process may either be a batch process or a continuous process.

Abstract: A method for recovering metals from solutions is described. A particular embodiment of the method concerns recovering copper metal. The method comprises first treating a solution containing copper ions with a sufficient amount of an inorganic acid to obtain a solution pH of from about 1.5 to less than about 2.5. A reducing metal, such as iron, is then added to the solution to precipitate metal ions, such as copper ions, as metals. The reducing metal has a mesh size preferably smaller than about 350, and even more preferably at least as small as about 400 mesh. The metal precipitate is recovered from solution.

Abstract: A process for removing dissolved oils and greases from an aqueous solution which also may contain dissolved heavy metals is provided wherein the aqueous solution is mixed with a source of ferrous ion and dithionite ion in a first step at acidic pH to reduce and permit removal of solid heavy metal, is present and to separate oils and greases from the aqueous solution. Solution from the first step if reacted in a second step with hydroxide slurries obtained from third and fourth steps. A second step solution from the second step is reacted in a third step with an alkali composition and a third solution. Optionally, the third solution is reacted with a chelating agent for iron and an oxidizer in a fourth step. A solution of chelated iron from the fourth step, when practical is disposed of. Oils and greases are recovered from the first step such as by skimming.

Abstract: A multistage treatment system for treating nutrient-rich water containing nitrogen compounds, phosphorous compounds, and other minerals. Three or more vessels or stages typically constitute the multistage treatment system. Each stage of the system is a reaction vessel having a first zone containing a substantially insoluble salt for precipitating phosphorous compounds and other minerals, a second zone containing a microorganism retained on an inert substrate for converting nitrogen compounds, and a separation device for removing precipitates from the water. The effluent from the multistage system may be further treated in ponds cultivated with aquatic grass.

Abstract: Disclosed is a method to remove heavy metals from amino-carboxylic acid chelate solutions comprising adding nitrous acid to lower the pH of the aqueous solution sufficient to destroy the chelate bonds and release the metal ions and thereafter adding an appropriate strong base and optionally a sulfide salt to precipitate the liberated heavy metals.

Abstract: Lead oxide is used for neutralizing the sulfuric acid wastewater received from washing charged (formed) electrodes during lead battery production. The neutralization product, including lead sulfate and excess lead oxide, is returned directly to production of the active mass paste. The mother liquor, after a possible use as cleaning water, is subjected to another neutralization with lead oxide, separate from the wastewater received from the electrode washing procedure in view of its possible content of impurities. The resulting lead sulfate is sent to a metal-processing facility for recycling. The neutral mother liquor, after the removal of lead residues by conventional precipitation methods and filtration, is discharged as treated water.

Abstract: A composition for treating water that contains metal ions and possibly also organic and/or inorganic compounds is produced by reacting sulfur with an alkali- and/or alkaline earth metal hydroxide in the presence of water.The inventive composition corresponds to general formula IM.sub.x S.sub.y O.sub.z, (I)whereM represents an alkali or alkaline earth metal,x is 1 or 2,y is in the range 1.5x-2.5x, andz is in the range 0.1-2.5.

Abstract: Aggregate-forming suspensions containing a coagulant therefor, e.g., FeCl.sub.3, polyaluminum chloride or Al.sub.2 (SO.sub.4).sub.3, are coagulated/flocculated by stirring to provide mechanically strong flocs of greater average diameter size, without concomitant formation of irreversible microflocs, and wherein the stirring regime, in at least the initial stage of coagulation/flocculation, includes an initial operating stirring cycle comprising (i) a rapid stirring sequence at an average velocity gradient ranging from 300 to 1,000 s.sup.-1 for a period of time ranging from 30 to 200 seconds, and (ii) a slow stirring sequence at an average velocity gradient ranging from 40 to 100 s.sup.-1 for a period of time ranging from 5 to 40 minutes.

Abstract: Disclosed is a process for removing by-product phosphorus-containing (PO.sub.x) materials, alendronate and alendronate byproducts from crude mother liquors in an omega amino-1-hydroxy-C.sub.2 -C.sub.6 alkylidene-1,1-bisphosphonic acid synthesis process, e.g. alendronate sodium. Calcium chloride is added first to the crude mother liquors, then calcium oxide to precipitate the PO.sub.x materials, then neutralized to about pH 7 to complete precipitation. Substantially all of the alendronate sodium active ingredient is removed from the precipitate. Following filtration, the PO.sub.x filtercake can then be disposed of by incineration, landfilling or reclamation of usable phosphorus as fertilizer. The remaining filtrate can then be further treated in an environmentally acceptable manner by wastewater treatment or recycling to the process.

Abstract: Phossy water is a toxic liquid waste that is generated when elemental phosphorus is manufactured, stored, or processed into phosphorus-containing products. Elemental phosphorus may be present as a solution, as colloidal particles, and as settleable particles.The primary objects of the invention are as follows:1. To provide a process for the disposal of phossy water stored at the TVA National Fertilizer and Environmental Research Center.2. To provide a process for the recovery of phossy water that will be generated when hazardous wastes stored at the TVA National Fertilizer and Environmental Research Center are recycled.Phossy water can be disposed of by using it to quench and granulate molten slag at electric furnaces used to manufacture elemental phosphorus. The elemental phosphorus content of the phossy water is limited to about 2 parts per million.

Abstract: A method for removal of water soluble organics from acidified oil process water is disclosed. The method comprises a step in which free oil is removed from such water by water-wet ultrafiltration to produce a water-rich filtrate stream which is then directed through a reverse osmosis membrane to produce a WSO-depleted stream and a WSO-rich reject stream. The method includes a recycle stream.

Abstract: Process water from pulp manufacture is purified in a separator device by mechanical or a combination of mechanical and chemical methods and is thereafter evaporated, at least part of the concentrate resulting from the evaporation being recycled and mixed with the process water fed into the separator device. In a preferred embodiment, a precipitant is added to the mixed water comprising the process water and the concentrate. The part of the concentrate not recycled and mixed with the process water is supplied, optionally after further evaporation, with an acid to a pH of 1-5, whereupon resulting flocs and precipitates are removed in a separator device.