Abstract: Method for removing suspended solids from a stream of waste water for subsequent use as an animal feed, wherein bentonite and an anionic polymer are added to the waste water which is maintained within a predetermined pH range. No metallic salts or other materials unacceptable as food additives are added to the waste water stream to facilitate flocculation of the bentonite and suspended solids. The pH range, maintained from 3.5 to 9.0 and optimally from 4.0 to 5.0, facilitates the coagulation of the suspended solids without the use of the metallic salts or other such additives. Microscopic air bubbles are used to float the flocculated bentonite and solids to the surface. In some cases the materials may be floated by gravity forces alone without the use of air bubbles. These floated materials are removed by skimmers or other top-floating solids removing apparatus commonly known in the industry and rendered into animal feed products.

Abstract: A method for treating and resolving a phosphorus containing oily waste emulsion is described. The treatment uses an emulsion destabilizing cationic polymer of low molecular weight in combination with filter aids to form a coacervate slurry. The coacervate slurry can be optionally treated with either high molecular weight anionic or cationic coagulents, or combination thereof. The suspended solids formed by the above treatments are removed from the slurries and wasted or discarded or incinerated. The remaining liquids may be recycled, reused, or treated as effluent meeting environmental standards.

Abstract: A method of removing Cr.sup.+6 from a solution is provided. In removing the Cr.sup.+6, an effective amount of an alkali metal dithionite is added to the solution to reduce substantially all of the Cr.sup.+6 to Cr.sup.+3. A soluble material is provided in the solution which will form a precipitate. Further, the soluble material is selected such that it will coprecipitate and tie up any dissolved or colloidal Cr.sup.+3 formed as a result of the reduction of the Cr.sup.+6. In one embodiment, the solution is alkaline and preferably, the pH of the solution is reduced sufficiently such that the soluble material will quickly precipitate and form the coprecipitate material with the Cr.sup.+3. Thereafter, the solution is filtered to remove the coprecipitated material from the solution and thereby form a supernatant solution suitable for waste discharge which has substantially lowered chromium values. The precipitate has the Cr.sup.+3 tied up in an insoluble non-leachable form.

Abstract: An apparatus for coagulating treatment which is capable of controlling the amount of addition of a coagulant to the optimum level thereby minimizing the water content of the dehydrated cake comprises coagulant adding devices (6), (7), and (8) for causing the coagulant to be added in a variable amount to a liquid subjected to the coagulating treatment, a heat transfer detecting meter (12) disposed so as to contact the liquid to which the coagulant is to be added, the liquid to which the coagulant has been added, or the filtrate from the liquid to which the coagulant has been added and adapted to detect a feeble change in the physical property of the liquid in the form of a change in voltage, and a control device (16) for controlling the amount of addition of the coagulant in the coagulant adding device (8) so that the value of detection of the heat transfer detecting meter (12) is minimized or kept within a desired range.

Abstract: A method for the decolorization of waste water containing coloring matters comprising dyestuff and/or pigment, in which PVA is added to a waste water containing coloring matters as above mentioned so as to catch the coloring matters in the waste water into the PVA, a precipitant of the coloring matters is added to the resultant waste water so as to render the coloring matters absorbed onto the PVA insoluble, a coagulant of PVA is added to the waste water so as to make the PVA insoluble, and then the thus insolubilized PVA containing the coloring matters is separated for the recovery thereof, and thus the decolorization of a waste water containing the coloring matters can be done skillfully and economically by eliminating the drawbacks in the conventional arts.

Abstract: A method of treating BCTMP/CTMP wastewater to improve retention and purification of cellulose fiber suspension and clarification of the BCTMP/CTMP wastewater which comprises the addition of a cationic, water soluble coagulant having a molecular weight less than 15,000,000 in an amount of about 1 to about 300 ppm; and a high molecular weight flocculant selected from the group consisting of: nonionic polymers having a molecular weight in the range between about 500,000 to about 30,000,000, low charge cationic polymers having a molecular weight in the range between about 5,000,000 to about 30,000,000, and low charge anionic polymers having a molecular weight in the range between about 5,000,000 to about 30,000,000, in an amount of about 0.1 to about 100 ppm.

Abstract: An aqueous suspension of coagulatable material is coagulated by adding polymeric coagulant to the suspension and then separating the resultant coagulated material from the liquor. The coagulatable material may be present in the aqueous suspension as a suspension of suspended solids or as colloidally dispersed solids. The suspension may be coal tailings or other aqueous (generally mineral) suspension. The polymeric material must be a low molecular weight, highly ionic, polymeric material. It is added to the aqueous suspension while in the form of polymeric particles having a size mainly above 30 .mu.m and that will dissolve into the suspension and coagulate the coagulatable material. A counterionic, high molecular weight, flocculant is generally added subsequently in order to flocculate the coagulated material.

Abstract: A process for removing at least a portion of any iron, copper, nickel and chromium ions that are chelated by a alkylenepolyamine polyacetic acid or salt in an aqueous liquid waste. The process comprises the steps of (a) adjusting the pH of the liquid to above about 10; (b) adding sufficient sodium sulfide to react with at least a portion of the copper ions; (c) separating precipitated iron and copper compounds; (d) adding nitric acid to adjust the pH to the range of about 6 to 8; (e) adding sufficient sodium nitrite to the liquid to react with at least a portion of the nickel and chromium present; (f) heating the liquid to above about 575.degree. F. for at least about 15 minutes to facilitate precipitation of nickel and chromium; and (g) separating precipitated solids to leave a non-hazardous filtrate.

Abstract: Phosphates which are dissolved or contained in suspension are substantially completely removed from a low-solids waste water which has been clarified. Precipitating and flocculating agents for transforming the dissolved phosphated to an undissolved form are added to the low-solids wate water and precipitation products and suspended matter are removed by microsieving through mesh openings in the range of about 10 to 150 .mu.m. Microsieving is preferably effected in two stages including a preliminary sieving through mesh openings from 60 to 150 .mu.m and a fine sieving through mesh openings from 10 to 80 .mu.m.

Abstract: A method of treating wastewater including a heat-curable (meth)acrylic monomer-containing composition, at temperature below that necessary to effect heat-curing of the composition. The wastewater may be produced by aqueous washing of porous parts impregnated with a sealant composition containing such monomer. The monomer-containing wastewater is (1) adjusted in pH to a value in the range of from about 8 to about 10, and (2) contacted with an effective amount of a reducing agent which is polymerizingly effective for the monomer, to yield corresponding polymer from the monomer. The wastewater is mixed with a cationic flocculating agent in sufficient quantity to flocculate the polymer in the wastewater, and the resulting wastewater is physically separated to recover a monomer- and polymer-reduced wastewater effluent which may be discharged to receiving waters.

Abstract: There is disclosed a pulsating sludge bed clarifier especially for the treatment of low turbidity waters, which uses incline plates in the sludge bed and some recirculated sludge. The clarification is greatly enhanced by recirculating a relatively small part of the sludge concentrate to a reactor chamber used for the premixing of water to be treated and the coagulant. The small amount of recirculated sludge cuts down significantly on the polymer flocculant, which is the most expensive chemical in the process that is required to be used, and can also serve to improve the adsorption of colors and similar materials, increase the density of the sludge blanket, and improve the rate of throughput of the system.

Abstract: Poly(diallylamine) blended with poly(N-methylolacrylamide) effectively detackifies over-sprayed paint in the circulating water of a wet paint spray booth operation. After detackification the dispersed paint is flocculated with hydrolyzed polyacrylamide, the paint waste is removed, and the clarified water is recirculated back into the paint spray booth operation.

Abstract: A method of treating wastewater containing (meth)acrylic monomer, such as is produced by aqueous washing of porous parts impregnated with a sealant composition containing such monomer. The monomer-containing wastewater is (1) adjusted in pH to a value in the range of from about 8 to about 10, and (2) contacted with an effective amount of a reducing agent which is polymerizingly effective for the monomer, to yield corresponding polymer from the monomer. The wastewater is mixed with a cationic flocculating agent in sufficient quantity to flocculate the polymer in the wastewater, and the resulting wastewater is physically separated to recover a monomer- and polymer-reduced wastewater effluent which may be discharged to receiving waters.

Abstract: A process is disclosed for reducing the turbidity of a Bayer process liquor containing a cationic polymer-humate complex comprising adding to said liquor a higher molecular weight, cationic polymer.

Abstract: A process for separately removing zinc and iron from acidic wastewater. The process involves adding alkali metal hydroxide to the acidic wastewater (below about pH 4) to achieve a first pH of about 4.8 to at most about 5.4 and precipitate an iron hydroxide-containing precipitate at this pH. The precipitate from the wastewater is separated and then additional alkali metal hydroxide is added to achieve a second pH in the range from about 8.8 to about 9.4. A zinc hydroxide containing precipitate forms at this second pH and is then recovered by filtration.

Abstract: Method for treating drilling effluents containing ligno-sulfonates wherein, successively, sulfuric acid is injected in order to cause coagulation, a cationic polyelectrolyte is injected to cause a flocculation and solids are separated from the liquid by centrifugation or dewatering compaction.

Abstract: A method for treating wastewater having a pH of between about 0.1 and 14 and containing dissolved heavy metals, in which a substantial portion of the heavy metals is precipitated as crystallized solids embedded within an insoluble monoclinic calcium sulfate crystal to produce a purified effluent having a pH of between 8 and 9.

Abstract: A non-toxic composition, and method, for the clarification of raw sugar-containing juices, especially sugar cane juice, and related products, for analysis. A composition constituted of A) aluminum chloride hydroxide, B) lime and C) activated bentonite, bentonite containing calcium aluminum silicate, and preferably also a polymeric flocculating agent, has been found highly effective as a reagent for the clarification of sugar-containing juices, notably sugar cane juice, and related products.

Abstract: A chelation process and apparatus for treating an acid solution, namely nitric acid photoengraving etchant, having a high concentration of magnesium and having a heavy metal contaminant produced by zinc leached during etching. The process requires adjusting pH of a batch quantity of the etch solution to a value permitting chelating to occur and mixing carbamic sodium salt hydrate chelating agent with the solution in quantity sufficient to cause precipitation from the solution of a carbamic salt compound precipitate of the contaminant, and separating the precipitate from the remaining solution by filter press for removal from the solution for safe environmental disposal. The remaining liquor is safely sewered. The apparatus is mobile for use on photoengraving premises.

Abstract: An integrated process for heavy metal and cyanide removal in aqueous waste stream from plating processes wherein cyanide is oxidized by hypochlorite at approximately pH of 11.5 and hexavalent chromium is reduced to trivalent chromium at ambient temperature with ferrous sulfate at pH of 9.5; excess hypochlorite from cyanide destruction reacts with ferrous sulfate and additional ferrous sulfate is added to reduce hexavalent chromium to trivalent chromium to allow hydroxide co-precipitation with hydroxides of the ferric iron and hydroxides of copper, chromium, zinc, cadmium, manganese, etc., which are then separated by settling and filtration.

Abstract: A process for improving a solid/liquid separation of tails from acidulated or non-acidulated liquors obtained by leaching phosphate ores or waste comprising: adding a mixture of dissolved polymers of hydroxyalkyl cellulose and polyoxyethylene into an aqueous slurry of leached phosphate wastes to obtain flocks of phosphatic clay wastes; allowing said flocks to settle into an agglomerated mass; decanting luqiid from insoluble residues to obtain tails having a solid content from about 55 to 70%.

Abstract: The dewatering of waste industrial and municipal sludges is improved by the use of clay employed with an unsheared, water-soluble, branched cationic polymer having a solubility quotient greater than about 30% and a branching agent content of from about 4-80 molar parts per million, based on initial monomer content.

Abstract: A dewatering porocess and apparatus for recovering water from waste drilling fluid for concurrent reutilization in an active drilling operation includes a storage area, an intermixer for introducing treatment chemicals into the waste drilling fluid and a centrifuge. Flocculation is chemically induced in the waste drilling fluid as it passes through the intermixing means for introducing treatment chemicals into the waste drilling fluid. The waste drilling fluid is then transferred to the centrifuge wherein it is separated into solid waste and clear reuseable water. The water is returned to the storagge area and may be chemically adjusted prior to being returned to the drilling rig.

Abstract: In the Bayer process for producing alumina from bauxite of the type wherein the bauxite is added to a caustic solution to produce a soluble aluminate solution and an insoluble red mud fraction which is then subjected to one or more separation steps to produce a thickener overflow which is then subjected to a Kelly Filter Press to polish the thickener overflow the improvement which comprises treating the thickener overflow and the filter aid with a filtration improving amount of dextran.

Abstract: Sedimentation in an inherently colloidally stable mixture comprising a suspension of solids in a liquid is controlled by a five-step process. In the first step a mathematical model representing a relationship between certain parameters, namely area product, viscosity and a parameter related to zeta-potential, is created. In the second step, zones in the model in which there is undesirably high viscosity are identified, In the thrid step, a model sedimentation path which skirts the high viscosity zones is superimposed on the model. In the fourth step, the actual mixture under consideration is monitored during a sedimentation process to obtain actual measured values of any or all of the critical parameters. In the final step, the parameters are adjusted as necessary to fit actual measured values to values on the model sedimentation path.

Abstract: A novel method of treating circulating water containing over-sprayed water-based or solvent-based paint, such as in a paint spray booth operation, comprises adjusting the alkalinity of the paint spray booth water by adding an alkalinity source thereto, contacting the oversprayed paint with the alkalinity-adjusted water and with an alumina coated silica sol added to the water, adding an effective amount of a polymer floccing agent to the water, and removing resulting sludge from the water.

Abstract: What is disclosed is a method of encapsulating hydrocarbon systems with the combination of an emulsifier solution and a reactive silicate solution. The method comprises the addition of an emulsifier solution to a hydrocarbon, for example, crude oil, then adding the reactive silicate solution to the emulsifier solution and hydrocarbon mix. Upon adding the reactive silicate solution the mix changes to a thick gel consisting of agglomerates of microspheres having typical diameters of 2 to 4 micrometers and less. The agglomerates are only loosely bound and the microspheres are easily dispersable into individual entities. Upon drying the wet gel yields a free-flowing powder. The encapsulation does not chemically alter or degrade the oil in any way.

Abstract: The soot obtained in the form of a soot-containing aqueous waste liquor in the course of synthesis gas manufacture is utilizable bya) mixing said liquor in a sewage sludge treatment plant with a sewage sludge to which organic flocculants are added as drainage aids with or without a further quantity of finely divided coal or ash,b) filtering this pretreated sludge mixture,c) incinerating the resulting filter cake andd) burying the ash in a sanitary landfill.

Abstract: A method is provided for removing a solid phase from a liquid substance, which is kept in a continuous turbulent flow. The method is characterized by adding simultaneously at consecutive places in the flow direction of the liquid substance, cement, iron (III)-chloride-sulfate and an anion polyelectrolyte. Cement is added at a first place, iron (III)-chloride-sulfate at a second place and anion polyelectrolyte at a third place.

Abstract: A method for recovering a fine particle size fraction of a negatively charged mineral from an ore, such as a kaolin clay crude, which comprises forming an aqueous pulp of the ore, dispersing the pulp by adding thereto sufficient water-soluble organic cationic dispersant to impart a positive zeta potential to said particles and, preferably, an acidic pH to said pulp, removing coarse particles from said dispersed pulp and fractionating the dispersed pulp to separate a fine particle size fraction of mineral particles from coarser particles.

Abstract: A process for purifying contaminated aqueous solutions without using ion exchange resins or organic solvents is provided. The process comprises contacting an aqueous solution with a non-polymeric getter compound in a dispersed state to remove dissolved contaminants or recover dissolved valuable materials. Suitable getter compounds having pendant long chain hydrocarbon radicals and complexing moieties are disclosed. The process is highly efficient and effective for removing a wide variety of dissolved contaminants such as metal ions, non-metal ions and dissolved organic contaminants such as dyes.

Abstract: The present invention provides a method of treating low-concentration turbid water, which comprises adding an anionic coagulant and a cationic coagulant in this order and forcedly stirring the mixture. According to the present invention, low-concentration turbid water of even up to 100 ppm can be cleaned to below 10 ppm at a high efficiency in a single treatment.

Abstract: The process according to the invention for the separation of oil-in-water emulsions by treatment of the emulsions with organic ionic demulsifiers and/or inorganic demulsifiers comprises carrying out the separation in two steps by first adding an organic cationic demulsifier to the o/w emulsions, and then adding an inorganic demulsifier, separating the oil phase from the resulting two-phase system and then treating the aqueous phase first with an inorganic demulsifier and then with an organic anionic demulsifier.

Abstract: In a Bayer process for production of aluminum, alumina trihydrate crystals are formed in the pregnant liquor and are flocculated using a combination of dextran and synthetic polymer, usually a homo- or copolymer of acrylic acid. The process is particularly advantageous where the liquor contains organic components such as humate and/or oxalate.

Abstract: A method for treating muddy water which comprises adding a first chemical containing an alkali metal or alkaline earth metal oxide or hydroxide to muddy water to be treated, thereby rendering muddy water alkaline, adding a second chemical containing an anionic polymer coagulant to muddy water simultaneously with or after the addition of the chemical, further adding a third chemical containing a sulfate thereby rendering the muddy water weakly alkaline, and then adding a fourth chemical containing an anionic polymer coagulant to muddy water. As a result, large-sized and hard flocs are produced.

Abstract: A method of dehazing a contained body of petroleum distillate by removing suspended water droplets from the distillate phase, or releasing free water trapped in an emulsion settled from the distillate phase, a detergent having been added to the petroleum distillate, comprising the step of adding to the distillate an effective amount of a vinyl copolymer which includes both a hydrophilic and hydrophobic monomer.

Abstract: A method is provided for oxidizing arsenic in an arsenic-containing solution. The method comprises contacting the solution containing arsenic in a +3 oxidation state with an amount of a specific type of oxidizing agent, i.e., an agent containing at least one ##STR1## wherein X is a halogen to effect substantially complete oxidation of the arsenic to the +5 oxidation state. The amount of oxidizing agent used is substantially less than that which would theoretically be required. In accordance with a particularly preferred embodiment, the oxidized arsenic is reacted with a metal to form a substantially water-insoluble precipitate, preferably an iron or calcium arsenate.

Abstract: A method of treating starch-containing water comprises the step of adding water swellable, cationic polymerizate particles to the starch-containing water. The starch is soluble starch. The water-swellable cationic polymer particles are polymer particles of a crosslinking monomer and either a cationic vinyl monomer or a cationic vinyl monomer and a nonionic vinyl monomer.

Abstract: This invention relates to a method of improving the dewatering of alumina trihydrate obtained by the Bayer process. The method comprises treating the alumina trihydrate with the product of mixing an alkaline liquor and a C.sub.8 to C.sub.20 fatty acid, fatty acid precursor such as an ester or amide, or a fatty acid blend. The product, a fatty acid salt, is an effective dewatering aid.The alumina trihydrate may be washed with a liquor including said product, or the product may be added to a Bayer liquor slurry prior to filtration of the alumina trihydrate.The invention also contemplates a watering aid consisting of the product of mixing an alkaline liquor with a C.sub.8 to C.sub.20 fatty acid or fatty acid precursor.

Abstract: Red mud in Bayer process liquors are flocculated using dextran and synthetic anionic polymer in the same stage, usually added separately to the liquor. The liquor may be the primary settler slurry, the secondary clarification liquor or one or more of the red mud washing stages. The process is of particular advantage where the liquors are high in carbonate content and/or total alkalinity.

Abstract: A control system having opto-electric detectors responsive to different solids concentrations and character of the solids of a slurry, the output of the detectors controlling the addition of a flocculants to the slurry to optimize coagulation of the materials in the slurry. The detectors having outputs sensing different slurry conditions with the detector outputs being processed to control the addition of different flocculants to the cell.

Abstract: The present invention provides a method of coagulating sludge, which comprises adding sequentially an anionic polymer coagulant and a cationic polymer coagulant to sludge, and furthermore, adding an anionic polymer coagulant.According to the present invention, it is possible to coagulate sludge at a far higher efficiency with a far smaller dewatering load than in the typical conventional methods using an inorganic salt and a pH adjusting reagent.

Abstract: A system and method for removing heavy metals, such as hexavalent chromium from water. The system comprises at least two reactor containers for independently mixing chemicals with water. The system further comprises a flocculator and a clarifier whereby each container can separately treat water therein and separately transfer the treated water to the flocculator such that water treated in batches at the containers can be treated in a relatively independent manner with relatively constant results. The method of chemically treating the water in the containers includes decreasing the pH value, adding a reducing agent and then increasing the pH value in preparation for precipitating the heavy metals in the clarifier.

Abstract: A process for clarifying liquors containing suspended solids is disclosed. The process is applicable to liquors having concentrations of suspended solids ranging from low to high, typically between 0.5 and 40 gm/l. The clarification process is characterized by the addition of flocculent and in excess of 50 gm/l inert particulate material so as to cause the formation of flocs comprising suspended solids and inert particulate material thereby to separate the suspended solids from the liquor. The inert particulate material is selected from silica sand, magnetite, limestone, ilmenite, hematite and calcite.

Abstract: An improved method for removing contaminants from industrial, municipal or food processing wastewater systems comprising generating amorphous precipitated magnesium silicate by separately adding aqueous solutions of magnesium chloride and sodium silicate.

Abstract: A method for treating industrial waste water prior to its discharge into the city or county sewer system is provided. The method includes introducing into the waste water an iron-containing compound, a hydroxide and a flocculating agent. This method results in the formation of a sludge cake layer on top of the waste water. The sludge cake is then removed, and the treated waste water is discharged into the sewer system.

Abstract: A method of removing a constituent of a biological fluid including a blood component, said method including flowing the biological fluid past one side of a first semipermeable membrane; flowing solution containing a first precipitation agent past a second side of the membrane so as to cause transfer of the precipitation agent through the membrane to the biological fluid so as to improve precipitation characteristics of the fluid; and precipitating the constituent from the biological fluid. Also disclosed are maintaining a lower pressure in a biological fluid in a dialyzer than in dialysate at all portions of a membrane in the dialyzer and adding a continuously flowing stream of concentrated precipitation agent to a continuously flowing stream of a biological fluid.

Abstract: A method and a device of dividing an aqueous processing waste solution of a non-silver halide light-sensitive material into solid and water are disclosed comprising the steps of:(a) introducing said solution into an evaporator,(b) concentrating by heating said solution,(c) removing sludge produced from the evaporator during concentrating by heating said solution,(d) separating the sludge into solid and liquid and(e) cooling and condensing evaporated gas to liquid.

Abstract: A method of processing an aqueous feed liquid to precipitate at least one metal (e.g., copper, nickel or a combination thereof) in a form to make the metal subsequently removable from the feed liquid by filtration, comprises the initial step of mixing (i) an aqueous feed liquid containing a soluble salt of the metal to be removed, (ii) oxalic acid in excess of that required to react with metal, and (iii) a pH-adjusting liquid in a quantity sufficient to lower the pH of the feed liquid to a point between that at which the feed liquid becomes slightly supersaturated with respect to the oxalate of the metal and that at which precipitation of the metal oxalate is initiated. The mixture is then allowed to stand (either at room temperature or heated to elevated temperatures) for a period of time sufficient to form metal oxalate, and finally the formed metal oxalate is separated from the feed liquid to leave an aqueous liquid suitable for discharge to a sewer line.

Abstract: A novel polymer and treatment scenario which considerably improves detackification of paint overspray consisting of high solids enamel, epoxy resin, or polyurethanes in the wash water or paint spray booths is disclosed comprised of:(i) a hydrophilic-lipophilic copolymer in combination with a modified tannin and/or(ii) a diallyldimethylammonium chloride polymer in combination with a modified tannin.