Abstract: A waste water treatment system including an anaerobic tank for treating phosphorous contained in initial waste water, a pair of anoxic tanks for treating nitrate in the waste water from the anaerobic tank, a holding tank for containing therein the waste water from an anoxic tank, an aeration tank for treating an organic material contained in waste water from the holding tank by microorganisms and pure oxygen and for treating ammonia by microorganisms to convert the ammonia into nitrate, with the aeration tank being a substantial cylindrical body mounted on a concrete bottom provided with an inclined eccentric slope for causing the waste water to eccentrically flow within the aeration tank, having a diffuser for diffusing compressed air into the waste water in the aeration tank, and a pure oxygen generator, and with the anaerobic tank, the pair of anoxic tanks and the holding tank being mounted around the aeration tank, a sedimentation tank vertically combined with the aeration tank and communicated therewith,

Abstract: A method and apparatus for treating waste liquids containing body fluids so as to prevent problems such as nosocomial infection due to such waste liquids containing body fluids discharged from patients under (surgical) operation or treatment, particularly those waste liquids containing blood or an irrigation liquid used to irrigate the body cavity of such patient. The method includes collecting a waste liquid containing body fluids into a container, separating the waste liquid into a supernatant liquor and a flocculate within the container, discharging the supernatant liquor from the container, and disposing of the flocculate remaining in the container together with the container.

Abstract: A waste water system having an embedded separator capable of concentrating activated denitrified sludge, and recycling the denitrified sludge to an anaerobic cell, provides a highly efficient method and apparatus for sewage disposal. The basic system is described in several embodiments which are selected on the basis of the waste water content. The improved system minimizes dilution of mixed liquor, increases hydraulic retention time at the various process points, and conserves energy.

Abstract: There is disclosed a portable assembly for treating hazardous waste water having a plurality of paired filter units having filter mediums and operated at high filter rates to minimize solids build up wherein solids are caused to be smashed and broken by shear forces and wherein chemicals are sequentially added to facilitate solids reduction, to oxidize organic compounds and to precipitate dissolved solids and wherein the process stream is subjected to ultraviolet light to reduce organic loading and downstream ultra filtration units to further reduce solids followed by reverse osmosis and/or ionization treatment.

Abstract: A domestic water clarifier comprising a storage tank and a batch tank having an annular inner wall is described. Raw water is pressurized and injected into the batch tank along with a quantity of a flocculent chemical such that the raw water and the flocculent chemical swirl around the inner annular wall of the tank, thereby mixing the raw water and the flocculent chemical. The mixture is then allowed to stand, thereby separating into clarified water and floc. The clarified water is drawn off to the storage tank and stored until needed. The batch tank is then flushed to remove the floc and to prepare the batch tank for the next clarification cycle.

Abstract: A water treatment system having dosing control for providing treated water having very low organic and ionic contamination, that can be accurately dispensed. The water treatment system having dosing control includes a water inlet hydraulically connected to a pump having a variable speed motor. At least one water treatment device is hydraulically connected downstream of the pump, at least one outlet valve is hydraulically connected downstream of the water treatment unit, and a recirculation line is hydraulically connected from the outlet valve to the pump. The output of the pump is controlled by a regulating device connected to the variable speed motor. The system provides for lower electrical current usage and reduced acoustical disturbances.

Abstract: The present invention provides treatment of domestic sewage containing oil. The resulting products will be purified water, dry fertilizer, and fuel (gas and liquid) containing no contaminants that could pollute the environment. After the initial settling process, two parallel flows are created: one containing liquid plus crude sediment (0.2 mm and greater) and the other containing liquid and fine particles (less than 0.2 mm), the latter termed "settled domestic sewage". The two flows are treated separately. The settled domestic sewage after treatment in a low-pressure separator that will separate out liquid fuel, followed by aeration, ultrafiltration, and finally sterilization by ozone or chlorine, results in pure water. The biochemical treatment of the sediments results in the production of gas fuel containing mainly methane gas and solid product that after drying and disinfecting is converted into fertilizer.

Abstract: A process and apparaus for recovery water from raw sewage extracted directly from the sewer including a screen(2) operable to obtain from raw sewage a screened effluent having a maximum particle size of no more than 900 microns. The apparatus also comprises a first membrane separator(5) which is operable to filter the suspended solids from some or all of the screened effluent. The process also includes a second membrane separator preferably in the form of reverse osmosis filter(8).

Abstract: Method for sewage water treatment using suspended activated sludge where sewage water is supplied to the equalizing tank being then re-pumped to the activation tank from which is supplied to the post-sedimentation tank after the clearing process and from here, after the remaining sludge sedimentation, to the drainage. The activation process is automatically interrupted after a drop of the sewage water level in the equalizing tank below the minimum level setting and the excessive sludge is then pumped off from the activation tank. The sludge re-pumping is interrupted and the activation process restored owing to the subsequent raising of the sewage water level in excess of the operation level setting.

Abstract: An apparatus for the treatment and recovery of spent vehicle coolant that involves the following steps:a) removing the spent coolant from the engine;b) treating the spent coolant with sodium dimethyldithiocarbamate to cause dissolved metals therein to form insoluble particles;c) treating the spent coolant of step b) with an aqueous basic coagulating agent such as a polyquaternary ammonium compound in its hydroxide form;d) filtering the spent coolant from step c) through a set of filters and then through a bed of carbon particles, to produce a relatively cleaner liquid; ande) adding to the relatively clear liquid a combination of corrosion inhibitors, buffering agents and alkali, whereby the treated coolant can be recycled to the vehicle for effective coolant performance therein.

Abstract: A process for continuously controlling the pH value of an industrial process liquid removes impurities contained therein from the liquid and controls its pH value. If necessary, an aqueous solution having an acid or basic character is added. The purified process liquid having the desired acid or basic pH value is fed to the industrial process, maintaining the character of the aqueous solution constantly acid or basic by means of ion exchange resins and repeating the above steps. The system comprises a first tank (11) with a pH-meter (18) for the process liquid to be treated, a second tank (12) for the aqueous solution, pumps or the like (13,16) for recirculating the process liquid in the first tank (11) and supplying it to the industrial process and for recirculating the aqueous solution in the second tank (12), and a valve arrangement (20) for admitting to the first tank (11) the pH adjusting liquid to be added to the process liquid to be treated.

Abstract: This invention comprises a process and apparatus for producing purified drinking water from surface or ground fresh water sources using no chemical pretreatment or coagulants, by usage of a positively-charged filtration media to attract the typically negatively-charged suspended solids present in the water source. The process, which can be portable, includes a filtration system having a filtration/recirulcation/backwash component and a disinfection step. The process further includes a system controller which receives electrical signals from float controls to control the filtration, recirculation, and backwash steps. This process produces drinking water which meets or exceeds the guidelines set by the World Health Organization for turbidity and microbiological content.

Abstract: The wastewater treatment unit is operable under high intermittent flow rate variations. It comprises a first clarifier in which is carried out a gravitational settling of solids and a second clarifier comprising a network of parallel plates inclined with respect to the vertical and a portion defining a collecting pit. Each plate has an upper edge positioned at a height lower than the filling level of the first clarifier to define an overflow giving access to the collecting pit. The network of plates allows to carry out a further settling of solids to create a counterflow of settled matter toward the first clarifier and a flow of clarified wastewater falling in the collecting pit. A filtering chamber is positioned above the first clarifier and comprises a filtering media supporting a biomass for digesting the organic content of the wastewater coming from the second clarifier.

Abstract: A method and apparatus for wastewater treatment is provided which can prevent any decrease in permeation efficiency of a submerged membrane without involving an increase in operating cost and sludge generation, and which can treat high concentration organic wastewater efficiently and without dilution. The wastewater treatment method has the steps of: concentrating domestic sludge by means of a first submerged membrane to produce thick sludge; mixing the thick sludge into a water to be treated, and introducing the water to be treated which is so mixed with the thick sludge into an anaerobic treatment portion for anaerobically treating the same; and introducing the anaerobically treated water from the anaerobic treatment portion into an aerobic treatment portion having a second submerged membrane disposed therein to subject the water to aerobic treatment.

Abstract: A water purifier which produces ultrapure water from a variety of feed sources. The feed source water may be potable tap, distilled, deionized, or water treated by reverse osmosis. The water is passed through a first purification media (30) and then through a chamber (34) where it is exposed to ultraviolet light in the presence of titanium dioxide. The water is then passed through a second purification media (38) to a dispensing valve (40). Operating the dispensing valve (40) provides ultrapure water from the purifier having a specific resistance of at least 18.0 megohm-cm and a TOC count of less than one ppb.

Abstract: Disclosed is a system for processing relatively small volumes of waste water such as that found in residential home use. The system first comprises a chamber adapted to hold the waste water. The system further comprises a first filter adapted to remove course material from the waste water and a second filter adapted to remove fine materials from the waste water. The system further comprises a disinfectant chamber adapted to disinfect the waste water. The system comprises a pump adapted to pump the waste water from the chamber through the first and second filters, and the disinfectant chamber.

Abstract: A biological filter for purification of liquids has primary filtering stages (52a, 52b, 52c) of a particulate material and secondary filtering stages (54, 56, 58) containing a fine-fiber material. The particulate material and fine-fiber material are covered with a biofloc film. The primary filtering stages (52a, 52b, 52c) and the secondary filtering stages (54, 56, 58) form a succession of filtering groups, and liquid is caused to move through the succession of filtering groups. Liquid is aerated during movement through the succession of filtering groups.

Abstract: A method and apparatus for the removal of total cyanide from aqueous solution. The method includes the steps of placing the aqueous solution into a reaction tank, adding lime, ferrous sulfate, and acid to the solution in the reaction tank and agitating the resultant mixture for a reaction time of about one hour. The agitated mixture is transferred from the reaction tank to a clarifier tank and polyelectrolyte solution is added to induce iron-cyanide complex precipitate coagulation. The apparatus includes a reaction tank to hold the aqueous solution and a lime slurry tank, ferrous sulfate tank and acid tank in flow communication with the reaction tank. A pH control assembly controls the flow of acid from the acid tank into the reaction tank and a reaction tank agitation assembly extends into the interior of the reaction tank. The clarifier feed conduit extends between the reaction tank and a clarifier tank.

Abstract: In a method of biologically removing nitrogen and a system therefor according to the present invention, by utilizing the characteristics of AH bacteria as being nitrifying bacteria of nitrous acid type for displaying high activity at the high concentration of ammonium nitrogen and the characteristics of AL bacteria as being nitrifying bacteria of nitrous acid type for displaying high activity at the low concentration of the ammonium nitrogen, in the nitrifying process, operations capable of obtaining the maximum nitrifying speed in accordance with the concentration of the ammonium nitrogen can be performed, and the nitrifying reaction of nitrous acid type for producing nitrous acid as being an intermediate oxide material of the ammonium nitrogen can be performed.

Abstract: A materials treatment system which includes filtration and treatment of solid and liquid components of a material, such as a waste material. A filter or substrate assembly is provided which allows liquids to pass therethrough, while retaining solids. The solids are then incinerated utilizing microwave energy, and the liquids can be treated after passing through the filter element, for example, utilizing a treatment liquid such as an oxidant liquid. The filter assembly can also include an exhaust filter assembly which removes solids or particulate matter from exhaust gasses, with the retained solids/particulates incinerated utilizing microwave energy.

Abstract: An apparatus is disclosed for containing a microorganism culture in an active exponential growth and delivering a supply of microorganisms to an environment containing wastes for bio-augmenting the biodegradation of the wastes. The apparatus comprises a bioreactor and an operably connected controller. The bioreactor has a bioreactor chamber for containing a supply of microorganisms, a second chamber for containing a supply of water and inorganic nutrients, and a third chamber for containing a supply of organic nutrients. The bioreactor is operably connected to the controller in which a first pump is operably connected in fluid communication between the bioreactor chamber and the second chamber and third chamber, and a second pump is operably connected in fluid communication between the bioreactor chamber and the environment containing wastes to be biodegraded.

Abstract: A high-purity water producing apparatus has an excellent effect of environmental protection and is also capable of effectively removing boron. It comprises a pretreatment unit, and a double pass RO unit an EDI unit or a distillation unit or any combination thereof as principal deionization unit(s) but does not comprise any chemical-regeneration type ion exchanger. It further comprises a boron removing unit and the water treated by the principal deionization unit(s) is brought into contact with a boron-selective ion exchange resin.

Abstract: The present invention relates to a process and a treatment system for biologically removing phosphorus and nitrogen from wastewater. In the anaerobic contact and settlement zone 1, wastewater 7 is first mixed with the returned activated sludge 8 to form a mixed liquor which is then allowed to settle in zone 1, and organic matters present in influent are mostly taken up by the sludge. The supernatant from zone 1 is passed through an aerobic reaction zone 2, furnished with packings, for complete nitrification; the settled sludge from zone 1 is hold in an anaerobic zone 3 for a sufficient period of time for controlling the sludge carbohydrate content to low levels in order to enlarge the sludge capacity for phosphorus removal because the extended anaerobic sludge degradation in zone 3 is very effective in controlling the sludge carbohydrate content to low levels.

Abstract: A wastewater treatment system has at least one treatment chamber and at least one settling chamber. An influent conduit connects the treatment chamber to a source of wastewater. A pump is provided for transferring treated wastewater, the treated wastewater being a water/biomass mixture, from the treatment chamber to the settling chamber by way of a transfer conduit. An effluent conduit removes treated wastewater from the settling chamber. A treatment system is provided for treating water in the treatment chamber. A biomass conditioner in the transfer conduit conditions the biomass by removing energy from the water/biomass mixture.

Abstract: A recycling apparatus which preferably treats used antifreeze/coolant in four cycles is disclosed. The recycling apparatus includes a number of tanks for storing the antifreeze/coolant during the various treatment cycles, a number of containers for storing chemical reagents used to chemically treat the antifreeze/coolant and a number of filters used to capture impurities suspended in the treated antifreeze/coolant. During a fill cycle, the used antifreeze/coolant is introduced into a treatment tank and the concentration of the antifreeze/coolant is adjusted, if necessary, to a predefined range. During a mix cycle, the used antifreeze/coolant is mixed with various reagents to adjust the pH value, as well as to coagulate and flocculate the impurities. A reverse mixing and aspiration of the antifreeze/coolant in the tank during the mix cycle ensure that the reagents will mix well and react with the impurities in the used antifreeze/coolant to form a sludge.

Abstract: Method and apparatus are provided for separating coarse and ultrafine solids from a liquid stream to produce a substantially dry solids discharge and a clarified liquid. Apparatus is provided comprising a combination of a settling tank, a plurality of filter screens spaced along an endless link-chain conveyor, a screen vibrator and directed air streams. In operation, coarse solids settle preferentially to the tank bottom. Ultrafines solids remain in suspension. Relatively coarse filter screens are conveyed from a point outside the tank to traverse a prolonged path through the liquid. Ultrafine solids are captured on the screens, by filtering the liquid through an ever finer build-up of filter cake. The relatively large number of passes of the screens through the liquid provides effective filtering of suspended solids. Further, the screens dredge settled solids from the tank bottom.

Abstract: A deionized or high purity water producing method is describing wherein ions and non-ionic substances are removed. The method includes pretreating feed water to remove suspended non-ionic substances, containing the pretreated water with first and second ion exchange resins that include a boron selective ion exchange resin, and stratifying or mixing together the first and second resins within an ion exchange column. The boron selective ion exchange resin is included to remove boron ions contained in the pretreated water.

Abstract: Apparatus for treating a liquid containing suspended solids comprising a clarifying vessel and a number of filters positioned around the periphery of the clarifying vessel for receiving and filtering liquid from the clarifier. A filter may be backwashed by isolating that filter, filling the other filter cells with clarified liquid and draining them into the isolated cell to remove filter media contaminants.

Abstract: Friable solid material contaminated by oxidizable hydrocarbons such as petrochemicals is delivered into a system wherein that material is subjected to a series of physical and chemical reactions to separate the contaminants from the solid material. The system can receive solid material, separate coarse and fine material and suspend the fine material in an aqueous medium. The aqueous suspension is subjected to temperature adjustment and the addition of an oxidizing agent preferably hydrogen peroxide. The suspension is agitated for a period of time to allow the hydrocarbons to be oxidized. The gaseous oxidation products are stripped and separated from the residual solid material. The aqueous suspension of solid material and diluent are physically separated and the solid material may be returned to its point of origin after treatment. The process and apparatus for carrying out the process are preferably applied to soils containing hydrocarbon pollutants.

Abstract: A neutral dischargeable effluent is developed by reaction between an acidic, spent photographic fixer liquid and an alkaline, spent photographic developer liquid; the spent fixer liquid contains iron in solution, the iron being introduced in a de-silvering pretreatment of the spent fixer liquid. The two liquids are fed into a treatment chamber and are allowed to react in the treatment chamber to form a neutral liquid and precipitated iron-containing solids; the solids settle in the treatment chamber and the neutral liquid rises upwardly through a synthetic organic polymer fiber filter pad into a discharge chamber above the filter pad; fine sticky particles suspended in the rising neutral liquid are retained by the filter pad; a neutral effluent is discharged from the discharge chamber.

Abstract: There is provided an ultrapure water production system which allows recycled waste water to be microbially treated and thereby reclaimed without causing any clogging of treatment system due to abnormal propagation of microorganisms, and which allows ultrapure water with 1 ppb or lower TOC to be obtained. This ultrapure water production system includes a lower part having an anaerobic organism treatment part (12), and an upper part which is placed above the lower part via a separating wall W.sub.B having an opening (16) and which has a biological treatment equipment including an aerobic organism treatment part (1). Since lower anaerobic microorganisms and upper aerobic microorganisms consume nutrition sources for microorganisms, treated water which is difficult for microorganisms to propagate can be obtained. Further, not only TOC but also organic nitrogen compounds are treated by the microorganisms, by which treated water with low electrical conductivity can be obtained.

Abstract: A transportable water purification unit with a reverse osmosis water purification unit (ROWPU), particularly for military use, is arranged to process municipal and other chlorinated water without damage to the reverse osmosis filtration elements. A modular transportable dechlorination device is coupled between the inlet of the ROWPU and a source of chlorinated water, such as a municipal fire hydrant, swimming pool, etc. The dechlorination device has a number of tubes mounted on a frame, at least some containing integral reticulated metallic dechlorination elements, the tubes being interconnected by quick connect removable U-fittings at their ends, whereby access is obtained to the reticulated elements, which can be in cartridges, and the order of the tubes along the flowpath can be altered. The reticulated dechlorination elements preferably comprise a Cu--Zn (brass) alloy and have a surface area to volume ratio of 200 to 500, preferably 300 to 350.

Abstract: A defined current and aeration system for the aeration chamber of an aerobic wastewater treatment plant is disclosed. It includes the release of oxygenation gas or air into the aeration chamber through a diffuser or the like at a position such that the air injected into the tank provides the necessary amount of oxygen for aerobic bacterial digestion of the waste while creating a current or circulation pattern in the chamber that forces every portion of the fluid within the aeration chamber into circulation thus preventing the accumulation of solids as sludge in the wastewater treatment plant.

Abstract: The present invention relates to a water purifying system having hydrogen peroxide added therein which utilizes an improved UV lighting system with a baffle functioning to increase the exposure of microorganisms and molecular hydrogen peroxide to the UV irradiation. The increased exposure increases the kill rate and overall disinfecting capability of the system. In addition an ozonator can be utilized in combination with the improved UV lighting system which still further increases disinfecting efficiency.

Abstract: A reconditioning system which withdraws coolant from a machine tool sump, filters solids from the coolant, removes tramp oil from the coolant, kills bacteria in the coolant, and returns the reconditioned coolant to the machine tool sump. The reconditioning system includes a separator tank having a coolant inlet, a coolant outlet, and a coalescer pack located between the coolant inlet and the coolant outlet to separate tramp oil from the coolant. An ozone generator is connected to the separator tank for dissolving ozone into the coolant to kill bacteria, yeast and fungus. An in-sump pickup includes a flexible intake hose connected to the separator tank coolant inlet, a suction nozzle having a generally rigid tube attached near an angled or fluted inlet end of the intake hose, and a ring-shaped float encircling the rigid tube. A discharge hose connects the separator tank coolant outlet and the sump.

Abstract: Apparatus for and a method of reducing solids and controlling surges in the flow of effluent from the clarifier chamber of an aerobic wastewater treatment plant. The apparatus is mounted inside the clarifier chamber of the wastewater treatment plant and connected to an outlet pipe of the plant. The apparatus includes a cylindrical tubular weir positioned in a cylindrical housing connected to the outlet pipe of the clarifier. The surge control weir assembly restricts the flow of the effluent from the clarifier resulting in an accumulation of effluent in the surge control weir assembly from which it flows at a rate proportioned to the volume retained in the assembly and resulting in a settling of minute suspended solids in the clarifier chamber. The surge control weir provides a final screening of the effluent through aerobic bacteria which grow in the slots of the assembly to digest the last solid particles from the water as the water slowly passes through the assembly.

Abstract: The invention provides a multi-stage apparatus for continuous waste water filtration, comprising a first tank provided with a waste water inlet pipe to supply waste water containing suspended solids to the tank, means for adding a coagulant to the waste water and an outlet pipe, a second tank receiving the mixture of waste water and coagulant from the outlet pipe, the second tank being sufficiently large to allow larger suspended solids to settle and being provided with a lower, openable port for discharge of the settled solids and having an upper weir for discharge of partially-cleared water, a continuously-driven, non-taut perforated belt, having a surface positioned to receive, at a first location, a stream of the discharged, partially-cleared water, the belt perforations being sized to enable the passage of clear water therethrough while retaining fine and coagulated solids on the surface for subsequent discharge at a second location, and the belt being non-taut to form a trough for retaining a body of wa

Abstract: An integral activated sludge wastewater treatment system has a vessel having at least one internal baffle dividing the vessel into at least one treatment chamber and at least one settling chamber. The settling chamber is at least partially defined by a first wall of the baffle. The treatment chamber is at least partially defined by a second wall of the baffle. A recycle pump is provided for recycling aerated wastewater from the treatment chamber back into the settling chamber and inducing a downward sludge velocity in excess of the velocity that would be caused by gravity alone.

Abstract: A wastewater treatment system: The system entails an aerobic tank and an anaerobic tank. Wastewater enters the aerobic tank where it is aerobically treated. The effluent then flows to the anaerobic tank where it is anaerobically treated to remove nitrogen in the wastewater. A filter may be added to the discharge line from the anaerobic tank to remove any suspended solids emitted with the effluent from the anaerobic tank.

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: A system for treating wastewater using the activated sludge biological process by retaining and degrading biodegradable coarse solids. A receiving well contains both a pre-separator stage and an activation chamber arranged one after the other in a direction of through-flow. The preseparator stage has a sand catcher located at the bottom for receiving undegradable solids. A partition is disposed within the receiving well between the pre-separator stage and the activation chamber. A lower section of the partition is a wall separating the sand catcher from the activation chamber. At least a portion of the upper section of the partition is a screen that is inclined with respect to a vertical line, into the activation chamber by greater than 0.degree. up to 30.degree. to widen a space of said pre-separator stage above the sand catcher.

Abstract: Control of a water/wastewater treatment system is effected by sensing the oxidation reduction potential (ORP) at various parts of the system and using neuro-adaptive process control techniques to make adjustments when necessary based on the ORP values. Internal nitrate recycling, sludge return, organic substrate addition and/or aeration can be adjusted to achieve the desired environmental conditions. In the event that phosphorus removal is necessary, the system can be used to assure proper detention time needed for biological phosphorus uptake.

Abstract: In a method of treating an untreated flow of liquid charged with particles and/or colloids, the flow is caused to flow in a coagulation zone that is kept turbulent and in which the flow is mixed with a coagulant. The untreated flow and a granular material which is insoluble in and more dense than the flow are caused to flow in an intermediate zone in which the granular material is maintained in suspension. The flow with substantially all of the added granular material and the colloids or particles aggregated therein is caused to flow in a sedimentation zone in which a clarified effluent is separated from sludge consisting of the granular material and the aggregated particles or colloids. The sedimentation zone has an undivided flow cross section with no separator plates and the effluent is caused to flow therein at an average settling speed of at least 15 m/h.

Abstract: Metal ions and/or complexes of metal ions are removed from a solution by formation of an insoluble chelated complex of the metal ions and a polymeric precipitating agent. A two-step process of mixing the influent with the precipitating agent is used to induce rapid precipitation and obtain large, self-agglomerated precipitate without addition of flocculating agent and/or pH adjustment. In addition, parallel loops are employed to simultaneously discharge treated metal-free solution and effectively collect/remove the precipitate-containing sludge without interfering with each other. The metal capturing capacity of the polymeric precipitant is maximized by forcing the influent solution through layers of the collected precipitate and by recycling unsaturated metal-precipitant complexes in the processing loop.

Abstract: A flotation method and apparatus for separating a selected constituent from an effluent of an industrial process is provided. The apparatus includes a conditioning tank and a flotation cell. The conditioning tank allows mixing a flotation reagent with an effluent and includes a mechanism for also dissolving gas in the effluent within the conditioning tank. The flotation cell includes a dissolved gas flotation chamber having an overflow for recovering the selected constituent and a tailings drain. In addition, the flotation cell also includes an added gas flotation chamber having a sparger for injecting gas into the effluent, an overflow for recovering the selected constituent and a tailings drain.

Abstract: An ozone purifying apparatus comprises a float which is afloat in polluted water and which includes an ozone reaction region in which the polluted water is mixed with ozonide air for the purpose of carrying out an ozone processing on the polluted water and an oxidant removing region in which oxidant generated due to a reaction between the polluted water and the ozonide air in the ozone reaction region is removed. The ozone purifying apparatus does not occupy a wide space. Water levels in the float can be easily adjusted. Furthermore, the ozone purifying apparatus can be easily installed.

Abstract: Sweetening of hydrogen-sulfide polluted liquids such as water and those whose viscosity is not substantially greater, is accomplished in upright tanks of constant cross-section, which are substantially conventional except for man-way provisions which permit clean-out and replacement of contents. Each tank, which has a liquid inlet provision near its bottom, is divided by its contents into three sections: a lowermost turbulence-eliminating section, an intermediate reacting section, and an uppermost tranquil purified storage section. Increase in capacity to fill a constant demand is attained by simply increasing the depth of the reacting section, to the lessening of the purified reserve.

Abstract: Spent solutions from photographic processors are fed into a conduit (18) to which subsequently are added precipitating agents from a first source (22) and flocculating agents from a second source (28); so that, well grown or ripened clumps of flocculated solids are formed along the conduit before being emptied into a gravity collecting vessel and shipping container (38) from which clarified liquids are displaced by a mass (50) of accumulated flocculated solids, typically through a filter (58, 142, 150, 158, 162, 166, 220) for removal of any unsettled fines. Many of the clumps of flocculated solids become enlarged enough to individually extend across and substantially fill a cross-sectional area of the conduit. As a result, the enlarged clumps substantially block passage of and strain from the solution remaining fine particles which then adhere to the clumps.

Abstract: An apparatus and method for modifying waste water to reduce nitrate content and biochemical oxygen demand is provided. The apparatus includes an ammonification and denitrification region having a substantially anaerobic environment, a nitrification region having a substantially aerobic environment, and an effluent drainage region. Effluent circulates through the ammonification and denitrification region and the nitrification region to convert organic nitrogen-containing compounds in waste water to nitrogen gas and carbon dioxide.

Abstract: A filter system for a liquid, usually water, is disclosed. The system includes two filters, each having a housing and a filter medium located in the housing through which the liquid flows in one direction to be filtered. A pressure operated distributing valve alternates the flow of water from one to the other of the filters and pressure regulators and check valves or pressure regulators alone divert a portion of the filtered water to backwash the filter medium in the other filter.