Abstract: A waste water treatment process wherein an iron contactor or iron contact are immersed in a treatment tank, into which waste water flows. In the treatment tank sulfate reducing bacteria are made to coexist with activated sludge or biofilters, wherein a velocity of flow of agitating stream on the outer surfaces of said iron contactor or contactors is set at 10 to 20 cm/sec, under an aerobic treatment. Iron ions are made to elute from said iron contactor or contactors by utilizing electrochemical iron corrosion through the agency of oxygen concentration cells on the outer surfaces of said iron contactor or contactors on conditions that dissolved oxygen concentration in the treatment tank is 1 to 3.2 mg/l and the oxidation-reduction potential is -200 to -400 millivolts (mV). Under an anaerobic treatment, iron ions are made to elute by utilziing microorganism-corrosion on the outer surfaces of said iron contactor or contactors on condition that dissolved oxygen concentration in the treatment tank is 0 mg/l.

Abstract: An improved process for removal of soluble contaminants from wastewater is disclosed which provides significantly enhanced contaminant removal and overall process efficiencies. The improved contaminant removal process is especially suitable for treatment of industrial effluents having high levels of dissolved cyanide and arsenic contaminants. Wastewater undergoes multiple stage sludge treatment, wherein sludge is mixed with wastewater sequentially in a plurality of discrete reaction stages for relatively short retention times. Reaction conditions which promote chemical and/or physical reaction of soluble contaminants with sludge are maintained, and liquid/solids separation is effected after each sludge treatment stage. Oxidizing agent is preferably mixed with the wastewater prior to multiple stage sludge treatment to change the oxidation state of inorganic contaminants and remove cyanide contaminants from solution.

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 content of halo-organic pollutants in water is lowered to residual AOX values below 1 mg/l, preferably below 0.1 mg/l by adjusting the Fe.sup.2+ comtent of the water to 20 to 1000 mg/l, adding a precipitated or pyrogenic silicic acid, converting 20 to 1000 mg of the Fe.sup.2+ into Fe.sup.3+ by adding in an oxidation agent, preferably hydrogen peroxide, and separating the iron (III) hydroxy complexes formed and the silicic acid, which contain the halo-organic pollutants in an adsorbed state, at pH 5-10. The method can be controlled in a simple manner as regards the addition of Fe.sup.2+ and oxidation agent via the Fe.sup.2+ /Fe.sup.3+ redox potential.

Abstract: Methods are provided for removing contaminants from an aqueous solution to yield a less contaminated aqueous effluent. In one embodiment of the invention, the method comprises coprecipitating non-volatile contaminants (i.e., heavy metals, light metals, cyanide, phenolics, oil and grease, TSS, BOD, COD, and/or TOC) with a carrier precipitate which is formed in situ within the aqueous solution. In another embodiment of the invention, the method comprises partitioning volatile organic contaminants between a liquid phase and a gas phase. In yet a further embodiment, the above versions of the invention are simultaneously performed in the same reaction vessel.

Abstract: This invention relates to the removal of hypochlorite groups from aqueous effluent solutions, so as to permit the disposal of the effluent by deep well injection. More particularly this invention relates to the catalytic decomposition of such hypochlorite groups from scrubbing water effluent used to remove chlorine from a gaseous effluent, wherein a solid catalyst is dissolved, recycled and reprecipitated in situ.

Abstract: An improved process for removing dissolved metals from waste water using a recycle high density sludge is described. Specifically, the process comprises the steps of: (1) treating waste water containing dissolved metals with a recycle stream containing alkaline surface active recycle particles to precipitate the dissolved metals on the surface of the recycle particles; (2) treating a portion of the treated waste water containing metal precipitate solids with an alkaline reagent to form alkaline surface active recycle particles; (3) recycling the alkaline treated stream containing the alkaline surface active particles; and (4) separating the portion of the stream from step (1) not treated with alkaline reagent into a water component which is free of dissolved metals and solids and a sludge component which contains solids.

Abstract: A method and apparatus are disclosed for efficient endothermic processing of liquids and the precipitation of dissolved elements and chemical compounds. Improvements over prior systems include system layout, components and modes of operation of the system. Applications of the system include destruction of toxic wastes and sewage treatment, precipitation of chemical compounds and elements including metals from solution (brine, sea water, industrial waste), sterilization and water purification, catalytic formation of chemical compounds, and processing of hydrocarbons.

Abstract: A method is provided for removing heavy metal ions from an aqueous solution to yield a less contaminated aqueous effluent. The method comprises coprecipitating the heavy metal ions with a carrier precipitate which is formed in situ within the aqueous solution.

Abstract: A process for the heavy-metal decontamination of contaminated substances such as natural and industrial sludges, thermal residues and soils. The contaminated starting substance is treated with an acid and the dissolved metal salts are precipitated as metal hydroxides in the pH range of about 3.5-11. The exact control of the pH value makes it possible to isolate individual metal fractions which can be used as raw materials in the metallurgical industry.

Abstract: The invention relates to a process for the reduction in size of the pores of a filter medium for beverages, preferably beer. Silica sol is added to the beverage to be filtered. In order to be able to reduce the size of the pores of the filter medium in a simple manner and to adjust it to the requirements, upstream of the filter medium through which passes the beverage, silica sol is added continuously or in a batch-feed process using a tank, in such a quantity and controlled such that the silicic-acid precipitation, i.e. the transition from SiO.sub.2 primary particles to SiO.sub.2 secondary particles, has taken place before the beverage has left the filter medium. The resultant silicic-acid precipitation reduces the size of the pores without sealing them.

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 process is disclosed for working up the high-boiling, solids-containing residues obtained in the synthesis of organochlorosilanes which are hydrolyzed and then optionally oxidized, with oxygen-containing gases, comprising adding during hydrolysis and/or oxidation a surface-active substance which hydrophilicizes the surface of the solids.

Abstract: A process for clarifying and reclaiming industrial working fluids and/or outdoor working locations such as oil and gas well working fluids and pits. A treating agent is added to the fluid in an amount exceeding its solubility therein to precipitate soluble contaminants and to form a layer of treating agent over a lower layer of sludge at the pit bottom comprising insoluble contaminants and the precipitates. The layer of treating agent compresses the sludge and serves as a filter/barrier to increase the amount of overlying clarified fluid which can be collected. Following separation of the clarified fluid for disposal or reuse, the sludge is solidified by adding a further treating agent. The process is particularly suited for use in oil and gas well exploration wherein the treating agent is a particulate material including lime.

Abstract: A method of selectively removing selenium ions from an aequeous solution containing selenium ions comprises contacting the solution with an amount of ferrous ion effective to reduce the selenium ions to elemental selenium. The contacting is preferably conducted at a pH of about 9 and the ferrous ions are preferably provided in situ in the form of ferrous hydroxide. The method may further comprise removing ferric oxides to which the ferrous ions are oxidized, these ferric oxides containing the elemental selenium produced by the reduction of the selenium ions, and separating the ferric oxides from the elemental selenium by adding a strong acid thereto.

Abstract: A method and apparatus for water purification, wherein ions are released from electrodes during electrolysis and combine with impurities to form a floc which, in turn, absorbs other impurities. A moving bed of solid, non-conductive particles surrounding the electrodes is also provided to insure self-cleaning of the electrodes. The apparatus for carrying out the process comprises an electrolysis chamber containing a moving bed of solid particles surrounding the electrodes, an inlet conduit for contaminated water at one end of the chamber, and a conically extending flocculation basin at the opposite end of the chamber. The invention simplifies water purification processes and apparatus.

Abstract: A process is provided for reducing the silica content in silica-rich geothermal brine having dissolved heavy metals, particularly from brine which is flashed from a high natural pressure to a reduced pressure to convert some of the brine into steam, the flashing causing the brine to become supersaturated in silica. The process comprises combining a base material with the brine, in the brine flashing stage, to increase the brine pH from its natural range of about 5 to 5.5 to a range of between about 6.2 and about 6.6, with a pH of about 6.4 being preferred. The added base, which is preferably selected from ammonia, sodium or calcium hydroxide and sodium sulfide or polysulfide, reacts with heavy metals, notably iron, copper and lead in the brine to form a finely divided, insoluble compound or compounds which function as seed crystals onto which supersaturated amounts of silica are precipitated from the brine. The base may be added to the brine in an amount of between about 200 and about 400 ppm by weight.

Abstract: Process for removing Sr and heavy metals from water in particular from waste water by throughly mixing it with a solution of an alkali metal carbonate and/or hydrogen carbonate in a reactor containing a fluidized bed of suitable bed material. The obtained heavy metal carbonate crystals crystallize onto said bed material and the obtained heavy metal carbonate crystals in granular form are removed from the reactor from time to time.The heavy metals which may be removed are Ni, Zn, Cu, Fe, Ag, Pb, Cd or Hg.

Abstract: An improved method for detackifying over-sprayed paint, lacquer or enamel entrained in the circulating water of paint spray booths comprises maintaining in the wash water a small amount of an alkaline zinc solution containing ammonium hydroxide and ammonium chloride.

Abstract: Organic waste, especially organic household garbage, is leached in a leaching apparatus for washing out any water soluble organic substances and water soluble heavy metal salts. Air is supplied into the apparatus during the leaching for aerobically decomposing or rotting the organic substances. Non-soluble substances are discharged from the leaching apparatus for further treatment. A liquid flow-off component containing solved substances is withdrawn from the leaching apparatus, collected in an intermediate tank and introduced into an anaerobic solid bed reactor wherein anaerobic bacteria reduce or decompose the liquid flow-off component to form bio-gas which is withdrawn from the solid bed reactor for use or storage in a low pressure tank. The heavy metal salts are precipitated into water non-soluble sulfides and the flow-off is returned for further leaching to the leaching apparatus in a substantially closed circuit in which any lost leaching liquid is replenished.

Abstract: This invention is related to a process for filtering gases or liquids for removing liquid or solid impurities and is characterized in that one uses for filtering a fibre material which partly exhibits a layer structure, said fibres along the main part of the total fibre length exhibiting a direction which deviates less than 45.degree. from the direction of a main direction plane of said fibres, said filtering being performed so that the filtered medium is brought to flow away from the filter material through an outflow area in the filter material in which the flow direction is essentially parallel with the direction of the main direction plane of the fibres.

Abstract: Procedure for the consolidation of sludge, whereby this sludge is mixed with a small quantity of at least one calcium compound with a calcium oxide and/or calcium sulphate base, as well as with alkaline metal silicate and organic hardening agents in quantities sufficient to give the sludge durable and spadeable properties, with the characteristic that to the sludge containing a quantity of calcium compound an alkaline metal silicate and at least one non-phytotoxic organic hardening agent consisting of organic compounds containing more than 12 carbon atoms is added.

Abstract: A process in which ferric ion in water-soluble form is added to an effluent containing cyanide, arsenic and antimony and having a pH of about 5 to 9 and treating effluent with SO.sub.2 and oxygen in the presence of soluble copper to produce a treated effluent having very low contents of cyanide, arsenic and antimony.

Abstract: A noxious metal(s) containing waste material is treated with an acid solution of a metal of group VIIa or VIII of the Periodical System, preferably iron or manganese. Subsequently, the metal of group VIIa or VIII dissolved in the acid is precipitated as a metal hydroxide and simultaneously the noxious metal(s) dissolved from said waste by said acid solution are incorporated in said precipitating metal hydroxide.The waste material together with precipitated metal hydroxide is subjected to an immobilization treatment.Manganese hydroxide is particularly suitable for removing cadmium.An acid solution of iron and preferably simultaneously manganese to be used for treating the waste is obtained by dissolving oxysludge caught during iron or steel manufacture.The method is particularly for treating dredged harbor sludge.

Abstract: A method for dewatering phosphate slimes and recovering a liquid solution involves adding a calcium sulfate hemihydrate to the slimes, mixing the resulting admixture to effect formation of calcium sulfate dihydrate crystals in the admixture, and recovering a liquid solution from the resulting crystal-containing admixture.The calcium sulfate hemihydrate addition may be followed by addition of calcium sulfate dihydrate. The calcium sulfate hemihydrate addition may be preceded by acidification of the slimes to pH 1-3 with sulfuric acid, which addition may be followed by the addition of other calcium salts to the slimes.A sufficient amount of calcium oxide or calcium carbonate or both may be added to the recovered liquid solution to raise the pH of the liquid solution to a value above about 6.0. Mixing permits calcium phosphate salts to precipitate, allowing for separately recovering the calcium phosphate salts and a dephosphated liquid portion.

Abstract: A method of purifying waste water from oil well rigs in order that the water may be made suitable for reuse on the rig or disposed of conventionally is disclosed. The method incorporates a series of aerators and corresponding collection tanks to first aerate, then collect, the waste water a number of times. In each collection tank, sediment precipitates to the bottom of the tank, permitting the clearer water to overflow, or to be skimmed, from the collection tank. A soluble aluminum salt is added to the waste water at an initial stage of aeration in order to coagulate waste particles within the water and form solid precipitates which then settle to the tank bottom, permitting the clearer water to pass on to subsequent aerators and sedimentation tanks, until ultimately, the water may be disposed of without polluting or contaminating the environment.

Abstract: A process for the removal of at least one compound selected from the group consisting of an aromatic hydroxy compound or an aromatic amine having a water solubility of at least 0.01 mg/L from waste water containing the same, which comprises treating the water with a treating agent which consists essentially of peroxidase, at least one agent selected from the group consisting of alcohol oxidase and a straight chain C.sub.1 to C.sub.4 alcohol or glucose oxidase and glucose and an azide salt of the formula MN.sub.3.

Abstract: A method of purifying waste water from oil well rigs in order that the water may be made suitable for reuse on the rig or disposed of conventionally is disclosed. The method incorporates a series of aerators and corresponding collection tanks to first aerate, then collect, the waste water a number of times. In each collection tank, sediment precipitates to the bottom of the tank, permitting the clearer water to overflow, or to be skimmed, from the collection tank. A soluble aluminum salt is added to the waste water at an initial stage of aeration in order to coagulate waste particles within the water and form solid precipitates which then settle to the tank bottom, permitting the clearer water to pass on to subsequent aerators and sedimentation tanks, until ultimately, the water may be disposed of without polluting or contaminating the environment.

Abstract: A method for the treatment of geothermal brines to control the precipitation of silica is disclosed. A sulfate-rich liquid is introduced into geothermal brine within a production well prior to flashing or is introduced into the residual geothermal brine remaining after the brine has been flashed to produce steam. The sulfate in the liquid reacts with the barium, calcium, and/or lead salts within the brine to produce a colloidal suspension which serves to accelerate precipitation of silica from the brine and to adsorb the precipitated silica particles. The colloidal suspension with its adsorbed silica particles is then removed from the brine by conventional gravimetric or filtration methods.The method of the invention substantially reduces the deposition of silica in wellbores and in energy extraction equipment and facilitates removal of the silica from the brine. The method further reduces the deposition of silica in injection wells wherein the silica cleansed brine is discharged.

Abstract: A method for removing low concentrations of soluble copper in the form of cupric cation and cuprocyanide and cupricyanide anions comprises first adding ferric cation, or ferrous cation and a soluble oxidizing agent, in an amount in excess of the stoichiometric amount required to form the ferric salts of the cuprocyanide and cupricyanide anions, and after a predetermined time adding an environmentally acceptable soluble precipitant to precipitate substantially all of the remaining excess ferric cation. By this procedure, very small concentrations of soluble cupric cation and the ferric salts of the cuprocyanide and cupricyanide anions, which are typically present in such low concentrations that they remain essentially permanently suspended in colloidal solution, are removed by the insoluble ferric compound which is present in much higher concentrations.

Abstract: Pulp mill bleach plant caustic extraction effluent is decolorized using a primary or other sludge from a pulp and paper mill. The sludge is acidified and mixed with the effluent. After a short incubation period, the mixture of acidified sludge and effluent is raised to at least neutral pH, causing precipitation of most of the color in the effluent. The precipitated color may then easily be separated from the liquor by any conventional clarification technique. The method avoids the consumption of large quantities of expensive reagents or high transportation costs associated with the prior art decolorization techniques used on such effluent.

Abstract: A process for stabilizing silica-rich geothermal brine to prevent silica scaling comprises selectively providing a supply of ferric ions, allowing the silica-rich brine to combine with the ferric ions to form insoluble, iron-rich siliceous material and separating the insoluble siliceous material from the brine to form a brine having a silica content which is reduced below the saturation level required for substantially scale-free handling of the brine. In one embodiment of the process in which the brine contains sufficient dissolved ferrous ions, the process comprises selectively contacting the brine with an oxidizing agent, preferably by aerating the brine, to oxidize a selected portion of the ferrous ions to ferric ions, which then combine with silica to form the insoluble iron-rich siliceous material. The ferric ion content of an iron-deficient brine may be augmented by adding ferric and/or ferrous ions to the brine.

Abstract: A process for reducing the concentration of selenium ions in the Se(VI) oxidation state in an aqueous solution. The aqueous solution is admixed with a quantity of metallic iron. The iron reduces the selenium ions from the Se(VI) oxidation state to a lower oxidation state and then dissolves in the aqueous solution. If the pH level of the aqueous solution is above about 2.3, the selenium ions are reduced to at least the Se(IV) oxidation state and the dissolved metallic iron hydrolyses to form an iron hydroxide that precipitates. The precipitated material is separated from the aqueous solution to provide a solution having a lower concentration of selenium ions. If the pH level of the aqueous solution is below about 2.3, no iron hydrolysis is observed to occur. At least a portion of the selenium in the Se(VI) oxidation state is believed to be reduced to the elemental state. The elemental selenium then is separated from the aqueous solution to provide a solution having a lower concentration of selenium ions.

Abstract: A pumpable water-purifying dispersion containing iron(II)sulphate, the iron(II)sulphate being dispersed in an aqueous phase with a dispersing agent containing an alkaline earth metal and a basic anion. The best dispersion properties are obtained when the dispersing agent is calcium carbonate or calcium hydroxide, whereby the resultant composition having a content of up to about 70% solid iron(II) sulphate, calculated as heptahydrate on the total weight of the composition, can be obtained and handled without difficulty. The aqueous phase can, to advantage, comprise metal ions active in water-purification, such as Fe.sup.2+, Fe.sup.3+ and Al.sup.3+.The invention also provides a method for producing the composition.

Abstract: A method of removing ruthenium contamination from a radioactive liquid effluent, consisting in adding to said liquid effluent a reducing agent and copper ions, to form, in said effluent, a cuprous oxide precipitate on which the ruthenium is fixed, and subsequently separating the precipitate thus formed from the effluent, and an apparatus for performing this method.

Abstract: A process for precipitating heavy metals from wastewater containing sulfate ions by treatment of the water with sulfate reducing bacteria. Said bacteria will reduce the sulfate ions to hydrogen sulfide which in its turn will precipitate the metal ions in the form of metal sulfides. According to the invention the bacteria are cultured in one or more culturing vessels in the presence of a nutritive solution and a portion of the wastewater, and the resulting aqueous solution containing hydrogen sulfide produced by the bacteria is introduced into a precipitation vessel together with the remaining major portion of the wastewater.

Abstract: A contaminated carrier liquid in a chamber is cleaned by adding thereto oil particles having a charge and a composition that induces the formation of an hydroxide floc to form an intermediate filtering layer in the chamber. A top clean oil layer is recovered and a bottom clean aqueous layer is recovered. The intermediate layer can be treated to form a composition that can be recycled to form an hydroxide floc.

Abstract: Heavy Metals contained in industrial waste streams are removed therefrom by flocculation using a source of ferric ions and an alkaline material at a basic pH. Both the flocculated heavy metals and the coagulant chemicals are recovered by acidifying the floc to a pH of between 3.2 and 3.7. This liberates the heavy metals back into solution but does not destroy the floc particles. After separation and removal of the concentrated heavy metal solution, the floc is further acidified to completely dissolve it. This dissolved ferric ion containing solution may then be reused to treat succeeding portions of heavy metal containing waste streams. The concentrated heavy metals solution may also be recycled or the metals contained therein recovered for reuse or disposed of in an acceptable manner.

Abstract: A method of removing ruthenium contamination from a radioactive liquid effluent, wherein:(a) the pH of said effluent is adjusted to a value of less than 5 and copper ions are added thereto,(b) the effluent thus treated is brought into contact with iron to form a copper precipitate which entrains the ruthenium, and(c) the liquid effluent is separated from the sludge formed.

Abstract: A method for increasing the cross-flow microfiltration fluxes of waste waters containing suspended solids and/or emulsified oil through microporous thermoplastic tubes by including therein a calcium compound selected from Ca(OH).sub.2 or CaSO.sub.4. The calcium compound is present in the waste waters in an amount ranging from above the solubility limit of the compound to about forty (40) percent by weight of the waste waters. The Ca(OH).sub.2 can be added directly to the waste water. The CaSO.sub.4 can be included by reacting H.sub.2 SO.sub.4 and Ca(OH).sub.2 in the waste waters to form CaSO.sub.4 in situ. Alternatively, wet CaSO.sub.4 can be formed by reacting H.sub.2 SO.sub.4 with Ca(OH).sub.2 outside the water and then added to to the waste waters in the required amount.