Abstract: A dialysis machine is disclosed that incorporates a water treatment module, a dialysate preparation module having a dialysate circuit, and an extracorporeal circuit including a dialyzer and arterial and venous blood lines that connect to the patient. The machine accomplishes on-line disinfection of all the fluid circuits of the machine, including the water treatment module, the dialysate preparation module and extracorporeal circuit, the arterial and venous lines, and the dialyzer, by circulating water heated to a high level disinfection temperature (e.g., 80 degrees C.) through the fluid passages of the machine for a sufficient time (such as an hour) to achieve high level disinfection. After the dialysis session is ended, the patient connects the arterial and venous lines to ports in a disinfection manifold that places the arterial and venous lines into fluid communication with the heated water. Thereafter, the machine is ready to disinfect the fluid circuits including the extracorporeal circuit.

Abstract: A cloudy water recovery and recycling apparatus and method of use. The apparatus recovers cloudy water defined as water recovered from the rinse cycle of a clothes washing machine. The apparatus is comprised of an electronic controller, a storage tank, a trap having a lint screen, a pumping means, and a pressurized storage container. Water from a clothes washing machine is separated into rinse water and wash water by an electronic controller. The wash water is disposed of and the rinse water is strained to remove lint, collected in the storage tank, treated with dye and bactericide, pumped from the storage tank to a pressurized container and then utilized to flush at least one toilet.

Abstract: The invention relates to an improved apparatus and method for initiating and sustaining an oxidation reaction. A fuel, such as natural gas or hazardous waste, is introduced into a reaction zone within a pressurized containment vessel. A permeable liner is placed within the containment vessel and around the reaction zone. An oxidizer, preferably oxygen, is mixed with a carrier fluid, such as water, and the mixture is heated and pressurized to supercritical conditions of temperature and pressure. The supercritical oxidizer-carrier mix is introduced to the reaction zone gradually and uniformly, over a comparatively large area, by forcing it radially inward through the permeable liner and toward the reaction zone. A means and method for cooling the exhausted by-products and using them as a cleansing rinse are disclosed.

Abstract: A liquid treatment apparatus for removing potentially combustible substances from water includes a biological fluid bed reactor that is supplied by a first conduit with contaminated water and that treats this water, under aerobic conditions, before discharging it as treated effluent containing a significantly reduced concentration of contaminants. The liquid treatment apparatus also includes a gas dissolution apparatus for providing dissolved oxygen to the contaminated water flowing through the first conduit to sustain biological action in the reactor. The gas dissolution apparatus includes an oxygenator including a pressurized bubble contactor disposed in a recycle conduit connected between the outlet of the reactor and the first conduit.

Abstract: A water and energy recovery process for an ice rink is disclosed. The process includes softening and carbon filtering water for use as flood water on an ice rink. The water is then demineralized by reverse osmosis to produce flood water having a specific conductance of about 2 to 30 micromhos/cm. The demineralized water is heated to 90.degree. F. and utilized in a resurfacer to flood the surface of the ice rink. The ice shavings removed from the surface of the ice by the resurface are deposited into a holding means and melted by utilizing recovered heat from the ice rink's refrigeration unit. The melted water from the holding means is used as a coolant in the ice rink's refrigeration unit. The steps of the process are then repeated, utilizing the warmed water from the refrigeration unit.

Abstract: A portable wastewater treatment system for recycling an aqueous surfactant solution utilized in a parts washer assembly for cleaning parts. The system including a contaminated solution storage tank, a treated solution storage tank, and a portable wastewater treatment apparatus wherein contaminated aqueous surfactant solution is collected in the contaminated solution storage tank, withdrawn from the contaminated solution storage tank, injected with air and passed into a mixing zone where the mixture is sprayed with water. The treated solution in the mixing zone is passed into a quiescent zone where light sludge is passed to the top of the quiescent zone and heavy sludge is passed to the bottom of the quiescent zone, the treated wastewater being disposed between the light sludge and the heavy sludge and the treated wastewater being passed from the quiescent zone into a discharge zone where the treated wastewater is discharged therefrom. The heavy sludge is selectively discharged from the quiescent zone.

Abstract: A process is provided for the purification of water which is contaminated with environmentally undesirable components, such as halogenated hydrocarbons, wherein the contaminated water or the gaseous and/or liquid components present therein or derived therefrom are subjected to at least two of the following treatments: treatment with ozone, treatment of UV radiation, treatment with a solid catalyst. A combined treatment of ozone and a solid catalyst, such as activated carbon, is preferred. An apparatus for a co-current or countercurrent realization of the purification process is also provided.

Abstract: It is known to treat the effluent resulting from photographic processing apparatus. Such treatment takes the form of either neutralization where the effluent is mixed with a neutralizing solution prior to disposal, or evaporation where the effluent is heated to form a precipitate and a concentrated liquid portion prior to disposal. However, both these techniques have disadvantages they do not account for toxic particles which may be suspended in the solutions. Described herein is apparatus in which photographic effluent can be treated to provide harmless end products which can be disposed of directly. The apparatus comprises a mixing unit (10) in which the effluent (S1) is mixed with treatment chemicals (S2, S3, S4, P1, P2, P3) and is then passed to a separation unit (20) in which the treated effluent is separated into non-toxic liquid and solid phases. A computer (100) is used to control all stages of the treatment of the effluent.

Abstract: A fluid mixture from which an unsaturated hydrocarbon has to be separated, is passed in the first stage at superatmospheric pressure to one side of a first semiselective gas separation membrane with a non-porous active layer, and a liquid complexing agent is passed along the other side of said first membrane, where said unsaturated hydrocarbon is bound through complexation in the interface of membrane and complexing agent. In the second stage said unsaturated hydrocarbon is dissociated from the complexing agent through temperature increase, the mixture of complexing agent and dissociated unsaturated preferably is passed at superatmospheric pressure to one side of a second semiselective membrane with a non-porous active layer and the unsaturated hydrocarbon migrates to the other side of the membrane and is discharged. Finally, the complexing agent is recycled.

Abstract: The present invention comprises an improved method and apparatus for treating water in heat exchange systems. The present invention automatically and inexpensively provides an effective chemical to process water systems at times and in proportion to the need for water treatment in such systems. When used in evaporative cooling systems, the present invention adds the treatment chemical to the system via the make-up water. The make-up water acquires a substantially constant concentration of treatment chemical as it is passed through a device containing a treatment chemical. The constant concentration of chemical is achieved by dividing the make-up flow into two streams within the device, saturating the smaller of the two streams with chemical, and re-mixing the two streams. The biocide agent used in the preferred embodiment of the invention is prilled elemental iodine.

Abstract: A method for purifying an etching solution consisting of an aqueous phosphoric acid solution which has been used in etching of a silicon nitride film. In the process, hydrogen fluoride is added to an etching solution consisting of an aqueous phosphoric acid solution which has been used for etching of a silicon nitride film, and the resulting solution is heated to remove fluorides of silicon as reaction products of hydrogen fluoride with silicon compounds which have been contained in the etching solution together with vaporized water.

Abstract: Apparatus and process for removing relatively low levels of components, particularly organic components found in an aqueous stream in one or more stripping zones located in a process unit. An eductor means extending into each stripping zone is used to provide micro-fine gas bubbles which will dissolve the volatile components and carry them from the aqueous stream.

Abstract: A process for the recycling of used and contaminated water-based metalworking fluids comprising separation of solid contaminants by settling and filtration, and separation of unemulsifiable tramp oil, reduction in total dissolved solids, removal of destructive bacteria and fungi, and removal of odors and toxic gases by the injection of steam, said process not requiring the use of a centrifuge.

Abstract: An aqueous solution which contains ammonium polysulfide is proportionally added to the sour water, which contains cyanide ions, ammonium ions, and sulfide ions. At least part of the cyanide ions contained in the sour water is converted to thiocyanate ions by the ammonium polysulfide. The solution which contains ammonium polysulfide is prepared from an aqueous solution by oxidation in an electrochemical cell. That aqueous solution may consist entirely or in part of sour water.

Abstract: A process for the treatment of liquids containing sulfides comprising moving at least one injection wand into a tank containing the liquid to be treated, wherein the angle between the injection wand and the tank bottom or the angle between the injection wand and the wall of the tank can be altered, and injecting a treating solution through the injection wand to increase the reaction mixing between the injected treating solution and the liquid being treated.

Abstract: A method and apparatus to restore grey water resulting from a cleaning activity such as laundry using ozone as a cleaning agent in a closed loop system for recycling to preserve water, to reduce system size, and to enhance the efficiency of the cleaning system.

Abstract: An in-situ system for removing volatile organic compounds (VOCs) from groundwater. The technique includes gas-lift pumping and in-situ vapor stripping.

Abstract: The invention relates to an improved apparatus and method for initiating and sustaining an oxidation reaction. A fuel, such as natural gas or hazardous waste, is introduced into a reaction zone within a pressurized containment vessel. A permeable liner is placed within the containment vessel and around the reaction zone. An oxidizer, preferably oxygen, is mixed with a carrier fluid, such as water, and the mixture is heated and pressurized to supercritical conditions of temperature and pressure. The supercritical oxidizer-carrier mix is introduced to the reaction zone gradually and uniformly, over a comparatively large area, by forcing it radially inward through the permeable liner and toward the reaction zone. A means and method for cooling the exhausted by-products and using them as a cleansing rinse are disclosed.

Abstract: A method and apparatus for the treatment of an effluent containing an organic chlorine compound in the presence of a porous iron type metallic article and hydrogen peroxide thereby effecting oxidizing decomposition of the organic chlorine compound, operated by a procedure which comprises causing the organic chlorine compound having hydrogen peroxide incorporated preparatorily therein to be circulated through a closed vessel having the porous iron type metallic article disposed therein thereby effecting oxidizing decomposition of the organic chlorine compound and then simultaneously circulating and aerating the effluent containing the organic chlorine compound under the condition of keeping the upper part of the closed vessel in an opened state thereby effecting oxidizing decomposition of the organic chlorine compound or causing the gaseous phase stagnating in the upper part of the vessel to be introduced into the effluent.

Abstract: An improved process for oxidizing industrial spent caustic streams, whereby oxidation of spent caustic occurs in a unitary processing tower with three chambers that cooperate simultaneously to oxidize the caustic in the first chamber; to separate the caustic from the oxidizing gas in the second chamber; and, in the third chamber, to pass gas and cooled caustic through a mass transfer apparatus that cools and cleans the gas and releases the caustic and gas into a gas-liquid separation zone of the upper chamber. An alternative embodiment of the invention involves spatially separating the upper chamber from the other two chambers.

Abstract: The present invention is a gas scrubbing system for removing hydrogen sulfide gas from a wastewater system. Pumps draw wastewater from a wastewater source within the system for injection through aerators which aerats aspirate hydrogen sulfide gas and oxygen from the wastewater source. The aerators mix the wastewater with the hydrogen sulfide gas and oxygen which is returned to the system as oxygenated wastewater containing elemental sulfur. The water and sulphur are then delivered to the treatment plant for final treatment.

Abstract: The water remediation and purification apparatus includes a cavitation nozzle which is operated with a throat size and pressure drop to incur cavitation in the water. The explosive and implosive bubble growth and collapse produces free radicals which interact with contaminants in the water to oxidize the contaminants. The cavitation process is enhanced by (1) a variable throat nozzle, (2) recycling the product back through the nozzle for further oxidation, and (3) programmable control feedback. Subsequent ultraviolet radiation from high energy lamps, ion exchange and/or degassifying treatment can be employed to produce water quality within acceptable levels.

Abstract: A process for decontaminating radioactive material comprises the step of contacting the material with a dissolving composition to dissolve the contaminants in the material, said composition comprising a dilute solution of about 0.05 molar ethylene diamine tetraacetic acid, about 0.1 molar carbonate, about 10 grams per liter hydrogen peroxide and an effective amount of sodium hydroxide to adjust the pH of the composition to a pH from about 9 to about 11. Also included are the steps of separating the dissolving composition containing the dissolved contaminants from the contacted material and recovering dissolved contaminants from the dissolving composition that has been separated from the material. A composition for dissolving radioactive contaminants in a material, comprising a dilute solution having a basic pH and effective amounts of a chelating agent and a carbonate sufficient to dissolve radioactive contaminants is also provided.

Abstract: The method of removing hot liquid coolant from an internal combustion engine cooling system, which includes a radiator having a by-pass outlet, the method including applying suction to the by-pass outlet to draw a by-pass stream of hot fluid, including hot pressurized gas, from the radiator, thereby to reduce fluid pressure in the radiator; and then opening the radiator for safely removing hot liquid coolant therefrom; The removed liquid may be disposed of or treated in a zone or zones outside the cooling system; and returning the treated coolant liquid may then be returned to the cooling system.

Abstract: A method for heparin neutralization within a blood bag containing whole blood and CPDA anti-coagulant, or the like, recovered from an extracorporeal circuit having heparin induced into the blood for reuse in a patient without further treatment thereof, by use of commercially available components wherein a modified blood bag containing CPDA and whole blood is infused with a calculable amount of protamine.

Abstract: A filtering system with electrolytic action and method is disclosed which is adapted for filtering the water in swimming pools, spas, saunas, hot tubs, whirlpools and the like. The filtering system includes a pump for drawing water from a body of water and circulating this water through an electrolytic filter including a layer of electrolytic filter media of dissimilar metal particles or granules and returning this filtered water to the body of water. The filtering system not only removes sand and sediment but also prevents algae and fungus growth, kills bacteria, and eliminates the need for adding chlorine, bromine, and algacide to the water. In accordance with a preferred embodiment, the filtering system includes a bypass valve installed downstream of the pump to divert only a selected quantity of water through the electrolytic filter.

Abstract: In order to reduce the build-up of slime and/or film in plants which circulates water, non-sessile microorganisms are added in single form to the circulating water, whereby the quantity of microorganisms added is about 1 to 10.sup.10 microorganisms per kg of the total organic carbon (TOC) of the organic substances present in the circulating water.

Abstract: A system for reclaiming water which has been previously used for such purposes as washing vehicles includes both a diatomaceous earth filter for removing particulates and a carbon filter for removing organic contaminants. Reclaimed water which is in the system and not immediately required for use is continuously recycled by a pump so as to increase the removal of contaminants. A second pump moves the cleaned water into a pressure tank for use in washing. A substantial portion of the system is disposed below ground level with a lockable cover above.

Abstract: A process of purifying the gypsum slurry end product produced by a flue gas desulfurization process which incorporates fine solids separation/classifying, dewatering, mixing, and filtering to both achieve a useful gypsum product and to recycle as much process water as possible to the flue gas desulfurization process. This purification process separates the incoming gypsum slurry into a fine solids stream containing a disproportionate amount of impurities therein that are concentrated and subsequently disposed of and a coarse solids stream containing a large amount of gypsum therein from which a usable gypsum product is recovered.

Abstract: In a supercritical oxidation process, the oxidized supercritical fluid effluent (46) discharged from the upper region of the reactor vessel (10) is contacted with a cold quench liquid (66) so as to produce a relatively solids free vapor stream (53) and a liquid stream (51) containing the bulk of the precipitates and other solids carried over in the oxidized supercritical fluid effluent (46). The temperature of the resultant liquid stream (51) is maintained at a temperature below the solids solubility inversion temperature, typically below 600.degree. F., so as to dissolve a substantial portion of the precipitates and other solids collected therein.

Abstract: A process of producing a disinfecting BZ reaction comprising continuously adding, at a point in a system of continuously flowing water in which a reductant consisting of microbial life forms is present, halogens or halogen containing compounds which hydrolize to create two bistable systems at equilibrium. The first bistable system consists of Cl.sub.2, HOCL, OCl and chloramines in the water, and the second bistable system consists of IO.sub.3.sup.-, I.sub.2 and HIO in the water. The bistable systems when perturbed by the reductant will initiate an oscillating reaction certain of whose intermediate products are microbicidal.

Abstract: A method for purifying flue-gasses and other hot, oxidative waste gasses originating from industrial installations, combustion furnaces, engines and the like, whereby the hot gas to be purified is passed through at least one spraying chamber or -area and is contacted therein with a gas washing liquid, which is sprayed into the hot gas flow and cools the gas to below 100.degree. C., whereby residual liquids with a high C.Z.V.-value, which comprise complex builders, compounds of heavy metals, sulphur- and nitrogen compounds, and originating amongst others from fixing-baths and the like from the photographic, photochemical and galvanic industries, are used as gas washing liquid.

Abstract: An in-situ system for removing volatile organic compounds (VOCs) from groundwater. The technique includes gas-lift pumping and in-situ vapor stripping.

Abstract: The present invention relates to a two stage, multi-phase process for the rapid and economical purification of waste water which may contain solid wastes, and which does contain chemical and bacterial wastes wherein the waste water is first intimately intermixed with a gaseous oxidant comprising ozone and oxygen to remove solids, then resaturated with oxidant for the breakdown and destruction for chemical and bacterial wastes, and thereafter a predetermined portion of the treated water is recirculated through the system for retreatment while the remainder is first treated with ultraviolet light and then degassified prior to discharge from the system in its purified state.

Abstract: A solvent selected from the terpene hydrocarbon group and terpene alcohol group as a cleaning agent can provide effective cleaning of heating, ventilating and air conditioning systems which use hydrofluorocarbon or hydrochlorofluorocarbon or Freon refrigerants by using a solvent as described. Flushing through the refrigerant system condenser coils and evaporation coils removes any trace of excessive compressor lubricant which will be carried out with the solvent. The flushed materials carried out are biodegradable, thus are desirable from an environmental standpoint.

Abstract: Disclosed is a catalyst composition comprising a mixture of solid fumaric acid and solid barium chromate useful in removing impurities and residual moisture from such sources as organic drycleaning solvents and petroleum fuels, and methods of using the catalyst composition.

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: A method for the decontamination of a soil, sediment, or sludge containing toxic halogenated organic compound and containing water comprising the steps of mixing said soil, sediment, or sludge with a reagent capable of reacting with said halogenated compound and heating said mixture of soil, sediment, or sludge, and reagent in a reaction zone to an elevated temperature thereby forming a reaction zone vapor stream containing at least a portion of the water contained in said soil, sediment, or sludge and unreacted halogenated organic compound; condensing a portion of said reaction zone vapor stream under conditions suitable for the formation of a condensate stream containing substantially all of the halogenated organic compound in said reaction zone vapor stream, and a vapor stream containing water and trace amounts of said halogenated organic compound; recycling said condensate to said reaction zone; treating said vapor stream to remove trace halogenated organic compound and venting the so-treated stream to th

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: In a wet lime desulfurization of exhaust gases containing SO.sub.2 and fly ash, a method and apparatus for treating absorbent solution slurry-containing fly ash includes diverting at least a part of the absorbent solution slurry containing fly ash particles, separating the diverted absorbent solution slurry by centrifugal separation into the solid gypsum component and a liquid component of a suspension containing fine fly ash particles, adjusting the pH value of the suspension containing fine fly ash particles remaining in a filtrate to 6 to 9 by adding an alkali, supplying the pH adjusted suspension to a thickener, removing concentrated sludge from the thickener, passing overflow H.sub.2 O from the thickener to a limestone slurry tank, and passing slurry from the limestone slurry tank to the absorbent solution slurry as make-up feed. Ill effects caused by fly ash and HF in exhaust gases are avoided, the activity of CaCo.sub.3 in the absorbent slurry is maintained, and highly pure gypsum is recovered.

Abstract: A process for enhancement of chemical oxidation of oxidizable materials comprises storing the materials in suspended or dissolved form in a storage tank, pumping the material from the tank through an electrostatic treater, an ultrasonic ozone disperser, an ultrasonic treatment chamber, and a cooling unit. The material is then returned to the storage tank for subsequent treatments until a target oxidation is achieved. The ozone dispersed by the ultrasonic ozone disperser is first produced in an ozone generator and then enhanced magnetically before or at the point of injection into the treatment loop.

Abstract: There is described a process for the simultaneous chemical and biological elimination of solid and liquid waste and apparatus for performing this process in the form of a loop reactor corresponding to FIG. 1 in conjunction with a specially designed nozzle which ensures an intimate mixing of substrate with air and the spraying-in of oxidizing agents while permitting only a short contact time between the oxidizing agents and the substrate.

Abstract: Divalent silver oxide provides a source for divalent bactericidal silver ions in the presence of persulfate. This oxide is especially effective when applied to water used in industrial cooling towers, hot tubs and swimming pools and conforms to stringent EPA requirements of 100% kills of 100K/cc Streptococcus faecalis within 10 minutes. The oxide also can be used in water with exceptionally high salt content without halide curdy precipitate formation and will not stain the skin of users who may inadvertently be exposed to it.

Abstract: A process for purifying the effluent originating from urea production plants, consisting of three successive treatment stages, namely stripping of the volatile components, thermal hydrolyis of the urea and biuret in a plurality of zones traversed with piston flow, and final stripping of the volatile components produced by the hydrolysis.

Abstract: A system for cleaning radiator systems waste coolant, including a filter, a flush tank refinery, a source of cleansing chemical, a pump to circulate radiator coolant from the vehicle through the cleaning system back to the vehicle, a quick-connect conduit extending between the vehicle and the filter, a conduit extending from the filter to the flush tank refinery, a fill tank reservoir, a conduit with valve extending from the flush tank refinery to the fill tank reservoir, a quick-connect conduit with valve extending from the flush tank refinery to the vehicle, a conduit with valve extending from the fill tank reservoir and interconnecting with the quick-connect conduit extending from the flush tank refinery to the vehicle, a conduit with valve extending from the cleansing chemical source to the flush tank refinery, a source of basic chemical, a conduit extending from the source of basic chemical to the fill tank reservoir, a pH sensor in contact with a coolant conduit and a computer to regulate cleansing and

Abstract: A system for reclaiming water which has been previously used for such purposes as washing vehicles includes both a diatomaceous earth filter for removing particulates and a carbon filter for removing organic contaminants. Reclaimed water which is in the system and not immediately required for use is continuously recycled by a pump so as to increase the removal of contaminants. A second pump moves the cleaned water into a pressure tank for use in washing. A substantial portion of the system is disposed below ground level with a lockable cover above.

Abstract: The improved high pressure oxygen-saturated water treatment apparatus of the present invention functions to provide super-saturated oxygen treatment to waste water for purification thereof. The apparatus includes a pressurized treatment tank having a substantial longitudinal dimension, with a chamber separation plate forming two interconnected chambers in the tank. An input conduit for flowing waste water into the first chamber of the tank is provided. An oxygen input conduit is connected to the tank for providing oxygen-containing gas under substantial pressure within the tank. An oxygen output conduit is also disposed on the tank for receiving the oxygen-containing gas from the tank to form a pressurized oxygen-containing stream.

Abstract: An improved infectious waste treatment system wherein infectious waste is fragmented and converted to a liquid or liquid/sludge form and then is chemically disinfected in a precisely controlled and timed batch process. The disinfection process takes place in an airtight sealed container to insure against release of pathogenic agents into the atmosphere. The process produces a non-toxic and non-infectious liquid or liquid/sludge waste residue which can be safely released into a sanitary sewer, landfilled or otherwise environmentally disposed.

Abstract: A process for removing color and oxidizable organic matter from thermally conditioned sludge liquor is disclosed. The process comprises treating the liquor with 250 to 430 mg/l chlorine which removes 20 to 70 percent of the color and produces a chlorine residual in the liquor. The chlorine-treated liquor is mixed with a small volume of untreated thermal conditioning liquor to remove the chlorine residual, and the dechlorinated mixture is returned to the treatment plant influent for additional treatment.

Abstract: This invention concerns a method of treating water from a container with ozone. The water is withdrawn from the container in a main stream, then passed through a pressure-reducing means, and returned to the container. A part of the main recirculating stream is separated into a second stream. The second stream is treated with ozone and held for a sufficient period of time to allow substantially all of the ozone to permeate into the water. The second stream is then re-introduced into the main stream or directly into the container.