Abstract: The invention described in the specification is a method for removing hydrogen sulfide, volatile mercaptans and methyl sulfides from a paper mill condensate stream. In the method, carbon dioxide is injected into the condensate stream under pressure and the pressure of the resulting CO.sub.2 -enriched condensate is reduced rapidly to a pressure sufficient to cause hydrogen sulfide and volatile mercaptans to pass from the CO.sub.2 -enriched condensate to a gas phase. The gas phase containing hydrogen sulfide and mercaptans may then be recycled or burned and the treated condensate may be recycled for pulp washing. The method is very cost effective and can be easily retrofitted into existing paper mill systems without significant capital expenditures or production down time.

Abstract: A method for removing dissolved oxygen from alkaline water containing dissolved oxygen at a temperature greater than 250.degree. F. which comprises the step of: adding to said alkaline water containing dissolved oxygen an effective oxygen-scavenging amount of a water-soluble semicarbazide of the formula ##STR1## wherein R.sub.1 and R.sub.2 are selected from the group consisting of C.sub.1 -C.sub.10 alkyl, cycloalkyl, aryl, cycloalkyloxy and alkyloxy groups.Preferred materials are 4-phenyl semicarbazide, 4-isopropyl semicarbazide, 4-4-diethyl semicarbazide and carbazoyl morpholine. Below 400.degree. F., a catalyst is also required.

Abstract: A process for the destruction of organic compounds selected from the group consisting of nitriles, aromatics, heteroaromatics, amides, organic acids, aldehydes and alcohols from wastewater, comprising contacting volatilized wastewater with a catalyst at an elevated temperature in the absence of added oxygen, so as to convert volatile organic compounds and ammonia to a mixture comprising hydrogen and carbon dioxide which are separated and removed from the stream, yielding a purified aqueous stream, substantially free of organic compounds.

Abstract: Hydrolyzing organic waste material in a multi-stage reactor comprising a heated first stage, a further heated second stage, a still further heated third stage, and a fourth stage, with a valved exit way connected to the fourth stage and a valve entryway connected to the first stage.

Abstract: A water aerator (1) has a vertically oriented aerator tube (2) with a plurality of water-inlet apertures (3, 16) that preferably are downwardly slanted intermediate an air-inlet end and a water-outlet end of the aerator tube. The aerator tube is positioned linearly inside of a water-input sleeve (4) having a water-input aperture (5) that is proximate a top of the aerator tube. A bottom end of the water-input sleeve is sealed to a portion of the aerator tube that is vertically below the plurality of water-inlet apertures. A one-way air-inlet valve (7, 14) can be provided in an air-inlet conveyance (6) to the aerator tube to prevent possible excess input of water from escaping through the air-inlet conveyance. Pluralities of air-inlet conveyances and aerator tubes can be provided.

Abstract: A process for treating a pathogen-containing sludge of biological solids including the steps of mixing the sludge with calcium oxide, ammonia and carbon dioxide so as to elevate a temperature of the mixed sludge to between 50.degree. C. and 140.degree. C. and to elevate a pH of the mixed sludge to greater than 9.8, pressurizing the mixed sludge to a pressure of greater than 14.7 p.s.i.a., and discharging the pressurized mixed sludge. The sludge has a water content of between 65% and 94% by weight. Ammonia is added to the sludge in the form of either ammonia gas, ammonium hydroxide, ammonium bicarbonate or as a byproduct of the reaction of the calcium oxide with the water in the sludge. Carbon dioxide is added to the sludge in the form of carbon dioxide gas or a reactant of ammonium bicarbonate. The pressurized mixed sludge is discharged by flashing the sludge across a restricting orifice and by evaporating a liquid component of the flashed sludge.

Abstract: A water denitrification process is provided which comprises stopping the reduction of nitrate at nitrite, lowering the pH of the water, and then gas stripping the nitrite out of the water by using air as the gas in a sparger. This allows considerable savings to be realized based on the reduced chemical removal costs as compared to other water denitrification processes.

Abstract: A process and apparatus for treatment of sludge is provided. The process includes providing sludge in a substantially liquid form and an alkaline additive to a preferably substantially closed reactor vessel, mixing the sludge and additive to ensure said pH is greater than about 12, maintaining the pH for a predetermined period of time, optionally applying supplemental heat to the sludge mixture in the reactor vessel to a predetermined elevated temperature for a predetermined period of time, maintaining the sludge mixture in a substantially fluid liquid condition, and discharging the sludge and additive mixture from the reactor vessel in a substantially liquid form such that it lends itself to be handled by gravity flow. The apparatus provides means to accomplish the above process.

Abstract: Organic pollutants in wastewaters are wet-oxidized by addition of pure oxygen or an oxygen-containing gas at temperatures of 80.degree. to 330.degree. C., under pressures of 1 bar to 200 bar and at a pH value below 7. For the wet oxidation process, iron ions and digested sludge or surplus sludge from a biological sewage treatment plant are added to the wastewater.

Abstract: A structure for treating water used in public water supplies for removing dissolved gases. The installation includes a closed outer tank for storage of water and a vented inner tank for water aeration contained at least partially within the outer tank. The inner tank includes a column of packing media for aerating the water which is delivered from the ground water source to a point above the column. A flow of air is delivered into the outer tank above the water level, and an air inlet causes air to flow into the inner tank and through the column in counter-current flow to the water. The air is then vented to the atmosphere.

Abstract: A process and apparatus for pretreating microbial sludges in order to enhance secondary anaerobic digestion. The pretreatment process involves disrupting the cellular integrity of municipal sewage sludge through a combination of thermal, explosive decompression and shear forces. The sludge is pressurized and pumped to a pretreatment reactor where it is mixed with steam to heat and soften the sludge. The pressure of the sludge is suddenly reduced and explosive decompression forces are imparted which partially disrupt the cellular integrity of the sludge. Shear forces are then applied to the sludge to further disrupt the cellular integrity of the sludge. Disrupting cellular integrity releases both soluble and insoluble organic constituents and thereby renders municipal sewage sludge more amenable to secondary anaerobic digestion.

Abstract: An apparatus and method for removing contaminants from waste water directs the waste water through a first magnetic field. An ionic polymer is introduced into the waste water after the waste water passes through the first magnetic field, whereby at least some contaminants flocculate. Flocculated contaminants are separated from the waste water so as to form a waste water effluent. An oxidizing agent is introduced into the waste water effluent and the waste water and the oxidizing agent are directed through a second magnetic. The waste water is directed through a weir into a trough open to the atmosphere. Air is injected into the trough so that at least one gas within the waste water combines with the air injected into the waste water. The combined air and gas floats to the surface of the waste water and is expelled into the atmosphere. Foam is removed from the waste water in the trough.

Abstract: An apparatus and method for removing contaminants from waste water directs the waste water through a first magnetic field. An ionic polymer is introduced into the waste water after the waste water passes through the first magnetic field, whereby at least some contaminants flocculate. Flocculated contaminants are separated from the waste water so as to form a waste water effluent. An oxidizing agent is introduced into the waste water effluent and the waste water and the oxidizing agent are directed through a second magnetic. The waste water is directed through a weir into a trough open to the atmosphere. Air is injected into the trough so that at least one gas within the waste water combines with the air injected into the waste water. The combined air and gas floats to the surface of the waste water and is expelled into the atmosphere. Foam is removed from the waste water in the trough.

Abstract: An apparatus for treating water includes a vertically extending contact vessel, wherein water is contacted with ozone, and a return vessel which contains a column of water of a sufficient height to drive water through downstream solids separation stages. Ozone is removed from the water and the rate of ozone injection is monitored and automatically adjusted so that no great amount of ozone remains in water entering the solids separation stages. The ozone is generated in elongated elements that are cooled by the process water and that are positioned to serve as a static mixer for such water.

Abstract: The invention is a method for removing dissolved oxygen from alkaline water which comprises adding to alkaline water containing dissolved oxygen an effective oxygen-scavenging amount of a water-soluble carboxylate at temperatures above 400.degree. F. A preferred material is tartronic acid. At lower temperatures, a catalyst is also required.

Abstract: An apparatus for removing dissolved hydrogen sulfide from water including an atomizing tank defining an open end. A manifold is positioned adjacent the open end. The manifold defines an inlet channel having a first inlet port and a second inlet port. The first inlet port is in communication with aerated water containing dissolved hydrogen sulfide. An atomizing nozzle is in communication with the second inlet port for atomizing the water to cause the dissolved hydrogen sulfide to react with oxygen in the air to form sulfate in the atomizing tank. At least one filtering tank is in communication with the atomizing tank for filtering the sulfate from the water. The method of the present invention includes the steps of: (a) aerating water containing dissolved hydrogen sulfide with air at a predetermined pressure; and (b) atomizing the water to cause the dissolved hydrogen sulfide to react with oxygen in the air to form sulfate.

Abstract: The present invention discloses a photo-induced DNA-cleaving agent composition comprises N-aryl-N-(alkyl or arylalkyl)hydroxylamine having the following formula: ##STR1## wherein R is C.sub.1 -C.sub.6 alkyl, phenyl, C.sub.1 -C.sub.6 alkoxy, phenoxy, C.sub.1 -C.sub.6 alkoxycarbonyl, halogen or halo(C.sub.1 -C.sub.6 alkyl)wherein R.sub.1 is hydrogen, C.sub.1 -C.sub.6 alkyl, phenyl, C.sub.1 -C.sub.6 alkoxy, C.sub.1 -C.sub.6 alkoxycarbonyl, halogen or halo(C.sub.1 -C.sub.6 alkyl); R.sub.2 is hydrogen; R.sub.3 is hydrogen or phenyl; R.sub.4 is hydrogen, phenyl, hydroxylphenyl, methoxyphenyl, dimethoxyphenyl, dimethylaminophenyl or naphthyl. The present N-aryl-N-(alkyl or arylalkyl)hydroxylamine is stable in dark, but it can react with O.sub.2 to form HO.multidot. radicals under irradiation of UV light for a period of 2-3 hours. The HO.multidot. radicals then react with DNA to accomplish cleavage of DNA.

Abstract: Selenate ion is removed from a selenate ion-containing aqueous waste liquid by treating the aqueous liquid with an organic reducing agent in the presence of a photocatalyst while irradiating the aqueous waste liquid with an actinic radiation to convert the selenate ion into elemental selenium which is in the form of solid precipitates and/or hydrogen selenide which is in the form of a gas.

Abstract: Hydrogen Sulfide is substantially completely removed from a gas stream in a two-stage operation. Hydrogen Sulfide is first partially oxidized to sulfur dioxide and the sulfur dioxide reacted with part of the remaining hydrogen sulfide while the hydrogen sulfide not so reacted is subsequently oxidized, thereby removing all of the hydrogen sulfide from the gas stream.

Abstract: Corrosion of ferrous metal surfaces in an aqueous system, such as a boiler system, is inhibited by adding a first component and a second component, the first component being preferably carbohydrazide, hydrazine, or a salt thereof, the second component being selected from the group consisting of certain hydroxylamine compounds or mixtures thereof, preferably N,N-diethylhydroxylamine. The weight ratio of the added first component to the added second component is between about 4:1 and about 1:4.

Abstract: A system for the purification of contaminated water to produce potable water. The apparatus of the system may be mounted on a mobile platform for use in remote locations or may be sized and adapted for permanent installation. The process ozonates the contaminated water, while the water is maintained under substantially laminar flow conditions, in a series of vessels under countercurrent process flow conditions. The water is treated with sufficient ozone, and the apparatus provides a sufficient residence time, to oxidize pathogens and oxidizable matter. Residual ozone is substantially completely neutralized with ultraviolet radiation. Ozone off gas not dissolved in the water during ozonation is collected and any ozone in the gas is converted to oxygen to prevent ozone release into the atmosphere.

Abstract: A method for stabilizing an aqueous solution containing sulfite or bisulfite ions and a water-soluble metal catalyst. The method comprises incorporating a stabilizing amount of a alpha substituted carboxylic acid or salt thereof or a vinyl carboxylic acid or salt thereof in the solution. The carboxylic acid inhibits sludge formation when the aqueous solution is stored. The preferred carboxylic acid, citric acid, also enhances the oxygen scavenging rate of the sulfite and bisulfite when the solution is used to treat aqueous systems for oxygen removal.

Abstract: Water to be utilized is reacted with soda ash and lime to produce a less corrosive and foulant water. Reaction sludges are fed to a desulfurization unit, where SO.sub.x, NO.sub.x and CO.sub.2 abatement occurs; other industrial waste sludges and/or waters and/or gases can also be utilized in such connection. FIG. 1 is one of the possible process schemes of the present invention.

Abstract: A process and apparatus for treatment of sludge is provided. The process includes providing sludge in a substantially liquid form and an alkaline additive to a preferably substantially closed reactor vessel, mixing the sludge and additive to ensure said pH is greater than about 12, maintaining the pH for a predetermined period of time, optionally applying supplemental heat to the sludge mixture in the reactor vessel to a predetermined elevated temperature for a predetermined period of time, maintaining the sludge mixture in a substantially fluid liquid condition, and discharging the sludge and additive mixture from the reactor vessel in a substantially liquid form such that it lends itself to be handled by gravity flow. The apparatus provides means to accomplish the above process.

Abstract: Apparatus and process for injecting high concentrations of a treatment gas into a liquid stream which is devoid of undissolved gas or a gas phase. The liquid stream is passed through a gas inducing injector to receive treatment gas, and then is passed through a centrifugal liquid/gas separator from which entrained gases and liquid with dissolved treatment gases are separately withdrawn.

Abstract: A process wherein a particulate catalyst, which is disposed in at least two serially connected beds, is contacted by a hypochlorite containing liquid to decompose the hypochlorite and evolve oxygen is improved by arranging that the liquid flows in a direction counter to that of the evolved oxygen in each of the beds. The efficiency with which the hypochlorite is decomposed is greater than when the liquid is in cocurrent or alternating co and counter current flow.

Abstract: In place of the incinerator in the present GWTPs, the following is substituted therein: a first reactor treats the vapor phase of the gases being expelled out of the air stripper. These vapors contain gases of volatile contaminants. The vapors are mixed with ozone and pumped into the first reactor where they are further scrubbed and oxidized in a packed column in contact with high concentration hydrogen peroxide. The hydrogen peroxide flows downward through the packing column while the Ozone mixture is fed from the bottom. The combined effect of ozone and hydrogen peroxide serves as a powerful oxidizing medium. The hydrogen peroxide accumulated at the bottom is pumped to the top in a recirculation process to be reused. The hydrogen peroxide can be increased to high concentrations, such as 30%, and recirculated for optimum usage. The second reactor is designed for the water, that is, for liquid phase treatment.

Abstract: The invention is a method for removing dissolved oxygen from alkaline water which comprises adding to alkaline water containing dissolved oxygen an effective oxygen-scavenging amount of a water-soluble sulfoxylate. A preferred material is sodium formaldehyde sulfoxylate.

Abstract: Methods for removing e.g. odor-causing components from liquid sludge, and, in one embodiment, a process for sludge deodorization which includes pretreating the sludge to gasify certain components, reducing the size of solids in the sludge, feeding the thus treated sludge tea stripping tower and therein removing in a stripping gas undesirable components from a thin film of the sludge on the interior tower wall. Preferably, the treated sludge is dewatered. Products from the tower may be recycled for further treatment until a desired odor level is achieved or discharged from the process. The process may be batch or batch-wise continuous.

Abstract: A method for stripping ammonia from a film of digested sludge including flowing alkaline liquid sludge as a film on a tower's interior wall and flowing an ammonia stripping gas past the film creating a vapor containing ammonia and stripping gas; then disengaging the liquid sludge from the vapor in a tower disengaging zone.

Abstract: A process for the destruction of organic wastes and ammonia from acrylonitrile plant wastewater, comprising contacting volatilized wastewater with a catalyst at an elevated temperature so as to convert volatile organic compounds and ammonia to a mixture comprising hydrogen, nitrogen and carbon dioxide which are separated and removed from the stream, yielding a purified aqueous stream, substantially free of organic compounds and ammonia.

Abstract: A process for treating a waste sludge of biological solids including the steps of mixing the sludge with an oxide-containing chemical and sulfamic acid so as to elevate a temperature of the sludge, pressurizing the mixed sludge to a pressure of greater than 14.7 p.s.i.a., and discharging the pressurized mixed sludge. The oxide-containing chemical can be either calcium oxide, potassium oxide, or potassium hydroxide. The sludge has a water content of between 5 and 85 percent. The oxide-containing chemical and the acid are reacted with the sludge so as to elevate the temperature of the sludge to between 50.degree. C. and 450.degree. C. The pressurized mixed sludge is flashed across a restricting orifice or passed into a chamber having a lower pressure. The evaporated liquid component can be condensed and used as part of the process. The oxide-containing chemical is mixed with the sludge in an amount between 5 and 50 weight percent of the sludge.

Abstract: A method for complete treatment of septic tank effluent or other contaminated liquid by contriving for it to flow in an ultra-thin film over a surface treatment medium such as fabric or sand. It provides diffusive aeration, biological reaction and physical filtration on a molecular scale.The device transfers contaminated water, or other liquid, from a container to a final collector completely purifying the liquid in the process. The purified effluent can then be reused for household, industrial, irrigation or other uses, or disposed of as normal surface run-off in streams or lakes.To increase efficiency, said container encloses a progressively more finely pored media precisely situated with effluent seeping gradually through progressively finer pores to provide uniquely effective pretreatment.

Abstract: The present invention relates to various methods, such as an above-ground method and an in-ground method, of using a palladized iron bimetallic system for the dechlorination of chlorinated organic compounds from various effluents or contaminated soil containing the same. The use of palladized iron bimetallic system results in the dechlorination of the chlorinated organic compound into environmentally safe reaction products.

Abstract: An apparatus (10) for treating water in a circulating water system (12) t has a cooling water basin (14) includes a slip stream conduit (16) in flow communication with the circulating water system (12), a source (36) of acid solution in flow communication with the slip stream conduit (16), and a decarbonator (58) in flow communication with the slip stream conduit (16) and the cooling water basin (14). In use, a slip stream of circulating water is drawn from the circulating water system (12) into the slip stream conduit (16) of the apparatus (10). The slip stream pH is lowered by contact with an acid solution provided from the source (36) thereof. The slip stream is then passed through a decarbonator (58) to form a treated slip stream, and the treated slip stream is returned to the cooling water basin (14).

Abstract: Process for purifying gaseous or liquid effluents containing sulphur-containing derivatives (H.sub.2 S, alkyl mercaptans, SO.sub.2).This process comprises: (i) basification of the effluent to be treated at a pH >9 in the presence of a base of general formula M--OH, in which M represents an alkali metal, an alkaline-earth metal, an agent for condensation between the organic part of the compound of formula I below and the sulphur-containing derivative or a phase transfer agent and especially a quaternary ammonium or a ligand; (ii) placing of the product obtained in (i) in contact with a compound of general formula I: X--(CH.sub.2).sub.n --CO--R, in which: X represents: a halogen, a sulphonyl halide of formula X'--SO.sub.2 --R', in which X' represents a halogen and R' represents a C.sub.1 -C.sub.20 alkyl group or an optionally substituted aryl group, an OH group; R represents: a C.sub.1 -C.sub.

Abstract: Corrosion of ferrous metal surfaces in an aqueous system, such as a boiler system, is inhibited by adding a first component and a second component, the first component being preferably carbohydrazide, hydrazine, or a salt thereof, the second component being selected from the group consisting of certain hydroxylamine compounds or mixtures thereof, preferably N,N-diethylhydroxylamine. The weight ratio of the added first component to the added second component is between about 4:1 and about 1:4.

Abstract: The present invention has two basic aspects: (a) a mechanical method for controlling the macrofouling of zebra mussels; and (b) a mechanical apparatus for reducing the dissolved oxygen of natural source water, such as for industrial or municipal use, to a level below that sufficient to support the survival respiration of zebra mussels.

Abstract: Raw water is made acidic so that the pH is not more than 4.5 and heated in the presence of an oxidizing agent to decompose TOC components in the raw water, and then deionized, thereby producing ultrapure water having a greatly low concentration of organic matters.

Abstract: A method of retarding the growth of algae in aqueous solution is disclosed. An aqueous medium is moved along a flow path in a direction terminating at an aqueous solution into which the aqueous medium is added. Before adding said aqueous medium into the aqueous solution, a gas stream having a nitrogen content in excess of 90% is injected into the aqueous solution in the same direction in which the aqueous solution is moved along the flow path. The gas stream is injected into the aqueous medium at a flow rate of at least 0.01 cubic feet per hour and said gas stream and said aqueous medium continue to intermix along said flow path prior to reaching the termination of the flow path at the aqueous solution.

Abstract: A process for the destruction of organic contaminants from wastewater streams and solid surfaces, including soil. The process comprises removing volatile organic compounds from the wastewater stream or surface by steam stripping and then contacting a stream comprising steam and the stripped organic compounds with a catalyst at an elevated temperature so as to convert the hydrocarbon portion of the organic compounds to a mixture of hydrogen and carbon dioxide.

Abstract: Viscous liquids, such as liquid sulfur and bitumen asphalt are contacted with gases to strip absorbed gases from the viscous liquid and/or transfer gaseous components into the viscous liquid using a shrouded impeller combination immersed in the viscous liquid. The invention has particular application to the stripping of hydrogen sulfide and hydrogen polysulfides from liquid sulfur using an oxidizing gas.

Abstract: Processes are disclosed for treating materials such as waste material, wastewater, and sludge, particularly waste activated sludge (WAS). In one aspect a process according to the present invention includes denaturing, acidifying and degassing incoming WAS while venting gases produced, preferably to a vent treatment system; feeding the resulting denatured WAS to a reactor into which are fed steam and oxygen, the steam discontinued once the reaction becomes autothermal; venting hot gases from the reactor back to the degassing step, to heat recovery or to a reactor, e.g. a sequencing batch reactor; and cooling and neutralizing the reactor product. Batch, semi-continuous, and batch sequencing methods are disclosed.

Abstract: A hydrated aluminosilicate material is used as a filtration media for filtering, including the removal of dissolved oxygen, water received by a carbonation apparatus, the particular hydrated aluminosilicate material having been crystallized under ultraviolet light to produce pore sizes of 75.ANG. to 200.ANG. at ambient temperatures (20.degree. C.-35.degree. C.) and in a low relative humidity (5%-20%).

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 treatment for controlling the deposition of scale imparting species on the structural surfaces of steam generating systems, wherein the aqueous medium is maintained at a pH which minimizes magnetite solubility, comprising the use of a combination of an organic amine and a nonionic polymer having the structure: ##STR1## wherein R.sub.1 is H or lower (C.sub.1 -C.sub.4) alkyl, R.sub.2 is (CH.sub.2 --CH.sub.2 --O).sub.n, ##STR2## or a mixture of both, n is an integer of from 1 to about 40, and R.sub.3 is H, lower (C.sub.1 -C.sub.4) alkyl or an acetate.

Abstract: An oxygen scavenger for aqueous mediums is disclosed. The oxygen scavengers comprise cyclohexanediones which, when added to basic aqueous solutions, effectively scavenge oxygen from the aqueous solutions. The oxygen scavenger has particular utility as an oxygen scavenger from water in heating systems such as boilers and heat exchangers.

Abstract: A method for deoxygenating water is provided comprising the steps of (1) adding an oxygen scavenger such as hydrazine, carbohydrazide, diethylhydroxylamine or morpholine to water containing oxygen, contacting the water and the oxygen scavenger with hydroxide, carbonate or carbonate/bicarbonate form strong base anion resin wherein the water within the bed has a pH greater than about 7; and (2) contacting the water containing the oxygen scavenger with the strong base anion resin for at least about one minute and removing from the bed water containing less than about 100 ppb oxygen. The method is especially useful in deoxygenating boiler feedwater and makeup water at substantially ambient temperatures during boiler start-up procedures.

Abstract: A process for the catalytic deodorization of and reduction of the nitrogen content in liquid manure tank effluents comprises:(a) in a basic medium catalytically oxidizing mercaptans into disulphides while simultaneously forming salts of hydrogen sulphide,(b) catalytically post combusting ammonia and amines to form nitrogen oxide,(c) catalytically reducing nitrogen oxides in the presence of a gaseous stream containing ammonia and amines.

Abstract: Raw water containing organic chlorine compounds is supplied in an aeration tank, wherein the organic chlorine compounds contained in the raw water are transferred into air or gas. The gas obtained from the aeration tank is collected in a treatment solution of a decomposition-treatment tank. The treatment solution contains an oxidizing agent and ultraviolet rays are irradiated to the treatment solution in the deocmposition-treatment tank to activate the oxidizing agent, to thereby oxidization-decompose the organic chlorine compounds in the gas.