Abstract: A device for removing hydrogen sulfide from well water having in situ activated carbon adsorbent regeneration. The device includes a tank with a water inlet, a water outlet and a steam outlet. The hydrogen sulfide adsorbent material is situated in the tank so that water entering through the water inlet must pass through the adsorbent material before exiting the water outlet. The tank also has a heating element which may be activated to boil water which is in communication with the adsorbent material. The water inlet, the water outlet, and steam outlet each have valves which are operated so that water may enter the tank and pass through the hydrogen sulfide adsorbent material and out the water outlet during water purification stage without any water going out the steam outlet.

Abstract: A high rate reactor for the treatment of biosludge has been designed which combines the processes of landfarming, sand bed dewatering, and forced aeration composting. The reactor is essentially a sand bed overlying a drainage system housed in an inflatable, pressurized building.The high rate reactor can effectively treat biosludge through dewatering and biodegradation. Volume reduction, stabilization, and solidification are achieved at improved rates over conventional practices. The reactor operates independent of climate and is a closed system minimizing environmental monitoring.

Abstract: A system to remove contaminants from water includes, in the pressurized water flow lines, a venturi nozzle assembly to entrain air in the water, a pressure tank to store and deliver the air laden water, an aerator/precipitator tank assembly to remove the excess air and any residual gases from the water in the pressurized system and to remove contaminants from the water and a filter tank having a filtration bed therein to remove the remaining precipitated contaminants from the water and to deliver the water to service.

Abstract: Upward-flow process for treating liquids in ion exchange filters containing cation exchangers and anion exchangers in separate layers arranged one on top of the other, in which the cation and anion exchangers are separated from one another by a resin layer which does not participate in the ion exchange, the anion exchanger is regenerated externally and the cation exchanger, which remains in the filter, is regenerated in the counter-current and the anion exchanger is removed from and recycled to the filter without whirling up the separating layer and cation exchanger layer. The invention furthermore relates to a new counter-current ion exchange filter for carrying out the process.

Abstract: In a method for separating solid reaction products from silicon produced in an arc furnace, molten silicon produced in the arc furnace in a reduction of SiO.sub.2 and carbon is filtered through a heated layer composed of SiC/Si after a so-called holding phase at a temperature in a region above a melting point of the silicon. The layer is preferably fashioned as a bottom plate of a crucible. The melt has eliminated from it SiO.sub.2 and SiC particles contained therein. The method serves for the production of silicon for solar cells. Due to the separation of SiO.sub.2 and SiC out of the molten silicon, an efficiency of above 10% is achieved in the solar cells fabricated from this material.

Abstract: A deep bed filter of the type comprising an upright vessel of particulate filter medium, inlet means at the top of the vessel for introduction of an aqueous stream to be filtered, outlet means at the bottom for removal of filtered liquid and means for backwashing the medium by an upward flow of liquid, has as the filter medium bone char and sand, the bone char being located substantially above the sand. The sand generally comprises a particulate mineral filter material selected from silica sand, fused alumina, garnet, zircon, ilmenite and glass.

Abstract: A method and apparatus is provided for holding first material along with less dense material in substantially separate layers and for effecting removal of at least some of the second material to a location displaced from the layer. The materials are arranged in the two layers with the first material at the bottom of a vessel and with the second material disposed above the first material. An elongate withdrawal conduit projects into the vessel to define (1) an exit port at the wall of the vessel, (2) a confined flow passageway communicating with the exit port within the vessel, and (3) at least one withdrawal aperture with the uppermost portion of any withdrawal aperture being lower than the uppermost portion of the exit port. The upper surface of the first material layer is maintained below the conduit while flow of the second material from the second material layer is effected into and through the conduit via the withdrawal aperture.

Abstract: A filter employing a discrete particle filter medium (3,11), such as graded sand or the like, in which the outlet passage (6) located at the bottom (1, 29,8) of a bed of filter medium is provided in which air can be employed in the backwashing process to agitate the filter medium. The filter has shallow coarser layers (9,10,28) of particulate material beneath the filter medium (11) itself and one set of outlet nozzles (14,19,27) having appropriately dimensional perforations positioned in the coarser or coarsest particle layer (9,28). In addition further finer perforated surfaces (16,23,30) communicate with the bottom of the filter medium (11) itself and the arrangement is such that when air is introduced perparatory to, or during backwashing the air emerges predominantly from the elevated finer perforated surfaces (16,23,30).

Abstract: An installation for continuously feeding and renewing, into the dampening fountains of printing processes, a solution comprising water and chemical additives, comprises a tank containing a solution that can be automatically replenished as to the percentage of water and chemical additives, by means of probes and automated devices controlling the level and some of the main parameters of said solution, e.g. acidity and density. The solution is refrigerated by a suitable apparatus and is agitated and stirred continuously by means of a re-circulation circuit which uses either ejectors or jet-pumps having their suction conduits connected to the discharge ducts from the printing press fountains which receive a proportional quantity of solution from a feeding circuit comprising at least one pump and filters.

Abstract: Apparatus for the separation of suspended solids from a fluid under pressure, by means of a granulate-bed, consisting of granulates of at least two sizes of grain of a material which does not swell during the filtration operation. During the filtration operation, the fluid flows through the granular medium filterbed in one direction and filtrate used for backwashing the separated solids flows in the opposite direction. The granulate-bed is held firmly together during the filtration operation and during the purification by a compression source, that generates such a compression on the granulate-bed, that it keeps the relative position of the granulate-particles with respect to each other in the granulate-bed, both under the action of flow during filtration process as well as during the purification process, in essence permanently in place.

Abstract: A filter device for removing organic contaminants from water comprises a filter housing having an inlet for water at one end and an outlet for water at an opposite end and three layers of filter material contained in the housing. The first layer is a hydrophobic organophilic silicalite capable of functioning as a molecular sieve and of adsorbing molecules as large as benzene. The second layer comprises a type I, strong base anion exchange resin of high porosity and high capacity while the third layer comprises activated carbon. The three layers are arranged one after another in series. Preferably the first layer is S-115 silicalite while the second layer is a copolymeric matrix made from styrene divinylbenzene. In the preferred embodiment the first layer of material is adjacent to the inlet.

Abstract: The invention concerns a counter-current adsorption filter for the treatment of liquids, with different adsorbents which require different regenerating agents, in which loading of the different adsorbents is effected in a stream of liquid flowing upwards and regeneration of the different loaded adsorbents with the different regenerating agents is effected in a stream of liquid flowing downwards, the inside of which filter is subdivided, by horizontal devices which are permeable to liquid, into a number of chambers corresponding to the number of different adsorbents to be used; in which the adsorbents which are regenerated with different regenerating agents are present in adjacent chambers; the chambers - with the exception of the topmost chamber of the filter - are equipped with a liquid drainage system which is located below the device which is permeable to liquid and forms the upper boundary of the chamber, and which is embedded in a layer of inert material; and in which the individual chambers are filled w

Abstract: A system for the rapid dewatering of sludge in large quantities makes use of a filter plate of design and construction capable of supporting heavy mechanized mobile equipment and without damage to the filter media. The filter plate features a monolithic plate of granular filter material used as the filtering medium in sludge beds for dewatering or reducing residual solids or sludge of potable water treatment systems. The filter material is made structurally rugged and with a smooth hard surface for the retention of sludge solids. The filter material is supported upon a substructure of aggregate providing approximately 40% internal voids for the gravity flow or drainage of filtrate and the back flow of chemicals and gases used in the rapid water reduction process. The assemblage is constructed of such strength as to allow for use of heavy handling equipment such as front end loaders in the removal of the dried sludge or cake upon the completion of the rapid water reduction process.

Abstract: A filter system for entraining solid matter contained in a fluid wherein a mass of particulate filter material is suspended in a fluid confined within an enclosure and the fluid containing the solid matter to be filtered therefrom is pumped into the mass of particulate filter material so as to cause weltering of the particulate material and gravitational separation of the solid matter from the fluid.

Abstract: A method for obtaining uniform stream in an adsorption column is disclosed. This method uses an adsorption column having at least one single-flow passage in which the ratio of the inner diameter of the column to the average particle size of a packing to be packed in the adsorption column is at least 20, and comprises classifying the packing to be packed in the adsorption column and packing the fractions of the packing into the adsorption column in the order of particle size. Thus, a desired substance or substances contained in a mixture can be adsorbed and then separated as a uniform stream in an adsorption column.

Abstract: An apparatus for the purification of salt brine having magnesium and calcium hardness includes means for treating a saturated salt brine containing magnesium and calcium ions with an alkali metal carbonate and an alkali metal hydroxide in a preselected sequence and in amounts in excess of stoichiometric proportions to form firm, readily settleable, filterable floc precipitate particles of insoluble compounds of magnesium and calcium, suspended in the treated brine and passing the resultant suspension to a filtering unit to separate and remove the floc precipitate and to provide a purified salt brine.

Abstract: A system for utilizing and disposing of sludge and other wastes employs an artificially created perched bed and a subsurface injector system that applies such wastes in a liquid or semi-liquid state to an aerobic portion of the bed. The solids from the waste mixture are suspended in the bed while the liquids percolate through the bed to an underdrain system for collection, monitoring, further treatment, ultimate reuse, or direct discharge. The system provides closed loop disposal of the waste stream in a completely controlled environment without impact to the local environmental system. The bed's selected media can be changed into a beneficial by-product--top soil--through the addition of the waste material. Subsurface injection may be accomplished by moving an injector sweep either by a vehicle supported on the artificial bed or by a movable superstructure. Repeated applications of sludge or waste may be made to the bed without plugging due to the disruptive action of the injector sweep on the bed material.

Abstract: A sludge treatment technique adapted for separating volatile liquid hydrocarbons and/or water from sludge solids in a horizontal enclosed tank having a supported bed of filter particles. Liquids are permitted to drain and evaporate under controlled conditions and a removable top closure permits exposure of sludge solids to ambient U-V radiation and weathering conditions whereby lead-containing sludge is detoxified to environmentally acceptable levels.

Abstract: A method of separating fine coal particles from refuse particles comprising the step of:(a) providing a coal filter cake(b) forming a slurry of fine coal particles, refuse particles in a liquid mixture comprising water and organic liquid,(c) contacting said coal filter cake with said slurry,whereby a major portion of said water and a major portion of said refuse pass through said filter cake and a major portion of said organic liquid and a major portion of said fine coal particles pass across the top of said filter cake.

Abstract: Modules for use in forming rigid filter beds by laying a plurality of the modules side-by-side upon a flat base are in the form of porous, planar elements having a continuous, polygonal upper surface, a continuous lower surface approximately coterminous to the upper surface, and sides normal to said surfaces of substantially equal depth much shorter than their length, such elements comprising laminated layers, each layer being formed of particulate material of substantially uniform size rigidly fixed together in a matrix of cured binder, the particles of the layers being substantially different in size than the particles of the adjacent layers, the top surface being flat and the bottom surface being channelled. In preferred forms, the modules' surfaces are square, there are only a top layer and a bottom layer, the top layer is much thinner than the bottom layer and the particles in the top layer are appreciably smaller than the bottom layer particles.

Abstract: The fluidized bed apparatus comprises, successively arranged in the upward direction along the vertical longitudinal axis thereof, a receptacle for coarser fractions, an upwardly flaring receptacle for medium fractions and an upwardly flaring receptacle for fine fractions. The fluidized bed apparatus further comprises grates extending perpendicularly to the longitudinal axis thereof in the receptacles for fine fractions and for medium fractions.

Abstract: The invention concerns a counter-current adsorption filter for the treatment of liquids, with different adsorbents which require different regenerating agents, in which loading of the different adsorbents is effected in a stream of liquid flowing upwards and regeneration of the different loaded adsorbents with the different regenerating agents is effected in a stream of liquid flowing downwards, the inside of which filter is subdivided, by horizontal devices which are permeable to liquid, into a number of chambers corresponding to the number of different adsorbents to be used; in which the adsorbents which are regenerated with different regenerating agents are present in adjacent chambers; the chambers--with the exception of the topmost chamber of the filter--are equipped with a liquid drainage system which is located below the device which is permeable to liquid and forms the upper boundary of the chamber, and which is embedded in a layer of inert material; and in which the individual chambers are filled wit

Abstract: Incompletely condensed aldehyde resin having a large surface area and formed in the presence of large quantities of water under mild conditions is used for removing waste products, such as urea, from the blood in hemodialysis or for removing such impurities from swimming pools or aquariums.

Abstract: A system for the rapid dewatering of sludge in large quantities makes use of a filter plate of design and construction capable of supporting heavy mechanized mobile equipment without damage to the filter media.The filter plate features a monolithic plate of granular filter material used as the filtering medium in sludge beds for dewatering or reducing residual solids or sludge of potable water treatment systems. The filter material is made structurally rugged and with a smooth hard surface for the retention of sludge solids. The filter material is supported upon a substructure of aggregate providing approximately 40% internal voids for the gravity flow or drainage of filtrate and the back flow of chemicals and gases used in the rapid water reduction process. The assemblage is constructed of such strength as to allow for use of heavy handling equipment such as front end loaders in the removal of the dried sludge or cake upon the completion of the rapid water reduction process.

Abstract: A regenerative filter having particular application for removal of oil from water. The filter includes a bed of finely divided particles or media separated in three horizontal layers. The top layer is comprised of anthracite particles, the middle layer of silica sand particles, and the bottom layer of garnet sand particles. The filter bed is supported within the filter vessel by a strata of relatively coarse support particles located beneath the bottom layer of filter media. The oil-contaminated water is fed into the top of the vessel and flows through the filter bed and supporting strata to a manifold at the bottom of the tower where it is discharged. By proper selection of the type and size of the media, effective removal of oil from the water is achieved during filtering and loss of media and intermixing of the layers is prevented during the back washing cycle.

Abstract: A bed of silver activated charcoal in combination with a downstream bed of a mixture of anion exchange resins and cation exchange resins aerate, purify, soften and dealkalize water flowing therethrough. Periodic flushing through a unit having a solution of sodium chloride or potassium chloride regenerates both exchange resins. An upright cylindrical container having screen separated compartments for the chemicals and filters receives tap water from a pressure reducing nozzle and discharges the conditioned water through a spigot. The unit containing the chemical regenerant is selectively connectable intermediate the nozzle and the container.

Abstract: A water filter includes a main housing defining a primary filter chamber in which is disposed an elongated tubular inner or secondary filter. Media arranged in the direction of flow includes, within the primary filter, layers of relatively coarse and fine flint gravel followed by a substantial layer of packed charcoal. The inner filter includes a substantial layer of packed charcoal and discrete layers of fine and coarse gravel near the outlet of the inner filter. The arrangement of media provides for repeated backflushings without contaminating the primary filter media. The main filter housing includes spaced apart head members which are interconnected by cylindrical tubular liners and an outer tubular shell disposed around the inner liners. The filter inlet and outlet conduits are provided with self-sealing quick disconnect coupler members for coupling the filter to a diverter circuit from the main water line or to a suitable circuit for backflushing operations.

Abstract: A receptacle has therein a lower bed of mixed anionic and cationic ion exchange resins and an upper bed of cationic ion exchange resins. The upper bed rests directly on the lower bed without any mechanical separation therebetween. Regeneration of the upper bed is achieved by removing the upper bed from the receptacle without removal of the lower bed. An output is located adjacent the boundary between the upper and lower beds. Pressure is exerted on the upper surface of the upper bed, and simultaneously a thin substantially horizontal spray of water is directed along a horizontal plane which is adjacent the boundary, thereby directing the water spray and the cationic resins of the upper bed through the outlet. The cationic resins are regenerated and returned to the receptacle to reform the upper bed. Prior to return of the regenerated cationic ions, the lower bed is dried by draining water therefrom to prevent the returning cationic resins from mixing with the resins from the lower bed.

Abstract: The upflow filter assembly includes a primary chamber situated above a secondary chamber within an enclosure and having a filter element spanning the primary chamber towards the upper end thereof. Airlocks are situated near the dividing floor of the two chambers so that when in the liquid treating or filtering mode, they operate to maintain the air/liquid interface between the chambers and prevent liquid from passing into the secondary chamber assisted by compressed air introduced into the secondary chamber. Liquid containing solids and/or flocculents, is fed into the primary chamber adjacent the lower side thereof and gradually fills the chamber with much of the flocculents and solids settling out by gravity. The partially deflocculated liquid then passes up through the filter element to a height above the filter element with excess, relatively clear effluent flowing out through an outlet spaced above the filter element to provide a hydraulic head above the filter element.

Abstract: Process for treating wastewater, which includes measuring the pH of the wastewater, adjusting the pH to about 10-11; filtering the wastewater; and subjecting the wastewater to ion-exchange treatment; and certain filter media.

Abstract: A process for the purification of salt brine having magnesium and calcium hardness includes the steps of treating a saturated salt brine containing magnesium and calcium ions with an alkali metal carbonate and an alkali metal hydroxide in a preselected sequence and in amounts in excess of stoichiometric proportions to form firm, readily settleable, filterable floc precipitate particles of insoluble compounds of magnesium and calcium, suspended in the treated brine and passing the resultant suspension to a filtering unit to separate and remove the floc precipitate and to provide a purified salt brine.

Abstract: A disposable bed filter for removing particulate matter and/or reducing oxygen in a poured metal melt is located within a trough. The bed filter preferably comprises discrete layers of bed media located in a trough between entry and exit baffle plates. The layers of bed media include a layer of coarse media and a layer of fine media. The trough is preferably provided with a closeable lid to permit removal of the bed media and to compensate for buoyancy of the bed media if present. In its preferred use, the bed filter forms part of a process for making a metal alloy wherein the bed filter simultaneously reduces the oxygen content of the melt and filters particulate matter from the melt.

Abstract: A hydrophilic oleophobic filter medium in granular form and composed of glass beads dispersed in a matrix of cured cement. The granules may be utilized in conjunction with naturally occurring materials, e.g., sand and/or anthracite. The granular density can be predetermined and varied. The granular shape is regular and controllable and the granular size can be graded for each density, so that the granules in a given filter level are of varient size, having a uniformity coefficient ranging from about 1.2 to 1.7. The method of making such granules includes the steps of casting a sheet of desired density and thickness, partially curing the sheet, severing the partially cured sheet to polygonal granules, curing the granules, optionally tumbling the granules, and finally screening them for final sizing.

Abstract: A method is described in which two or more granular filter media are used in combination in such a manner that the filter bed is backwashed using air and water simultaneously. The media size gradation and density are selected so that, although the media may be mixed during backwash, the media are separated into layers according to their density and/or size following termination of the simultaneous air-water wash and prior to returning the filter to the filtration mode. The simultaneous air-water wash step can be carried out without media loss by use of an appropriate media retaining procedure.

Abstract: Method of and a multilayered filter for softening and filtering water. The water to be softened and filtered flows through a first layer of particles of activated carbon, a second layer of beads of an organic ion cation exchange resin, a third layer of granules of sodium aluminium silocate, and a fourth layer of grains of filter sand which layers are arranged vertically in a tank. The filter comprises the four above identified layers of filter materials.

Abstract: The portable sink top water conditioner includes couplings for periodically recharging the water filtering and conditioning elements in response to an indicator signal generated as a result of deposition of a predetermined weight of material filtered from the water and retained by the conditioner. Filter elements for maintaining the bacteria count at an acceptable level may be incorporated.

Abstract: A blood detoxification apparatus comprises a housing filled with a plurality of substantially spherical reaction bodies. Each reaction body comprises an embedding material and active ingredient particles such as adsorbents and/or enzymes embedded in the embedding material which is blood compatible but nonpermeable for corpuscular blood components. The active ingredients may have a dust or powder or granular consistency but are substantially smaller in diameter than the reaction bodies which may be distributed in layers in said housing whereby the active ingredients in different layers may be different.

Abstract: An upwash sand filter with a diaphragm hold-down for the granular filter media during filter stage is operable with self-graded coarse-to-fine media for upflow filtration, downflow filtration, or combined up and down flow to a central exit filtration. The media is held in place by a diaphragm that may be a perforated plate for allowing liquid to pass through the perforations, and in the downflow embodiment, the media column is supported on another perforated wall or plate to allow a final lower layer of coarser media to be used so that the plate itself is not the finest layer of the filter. In the upflow embodiment, a coarser top layer is employed for this same purpose. The diaphragm serves in all embodiments to prevent loss of media and avoid channeling through the media thereby allowing exceptionally high filter rates.

Abstract: Sintered glass pellets which generally decrease in particle size as they increase in specific gravity provide a unique filter medium which varies from larger pellets at its inlet (upstream) upper portion to smaller pellets at its outlet (downstream) lower portion. In view of the variation in specific gravity, particles forming the filter medium generally resume substantially their initial respective positions after the medium is back-flushed for cleaning. Although pellets throughout the medium differ in specific gravity, they are made of the same ingredients. The individual pellets are formed by granulating finely-ground glass with a suitable binder and sintering the resulting granules.

Abstract: A filter for filtering contaminants from liquid, wherein the apparatus includes several distinct, adjacent layers of granular filter medium. The layers are carefully graded for size and density, with the granules constituting the layers increasing in density and decreasing in size in the direction of filter flow. At least some of the layers are composed of essentially uniformly sized and shaped, water-wettable synthetic granules of a specific gravity ranging from about 1.04 to about 1.5. For some applications, all of the bed layers are formed of such synthetic granules; for other applications, some of the layers, preferably the lower layers, are formed of naturally occurring materials, such as anthracite, sand, and fruit pit shells or nut shells. In either form of the invention, the distribution of density and size in the direction of flow--normally downwardly--is such that the layers readily stratify after backwashing to reconstitute the bed in its initial, most efficient filtration configuration.

Abstract: A waste water filtration and sludge removal system for filtering and removing sludge materials suspended in water resulting from steel pickling and cleaning operations and the like. The system includes a trough-like filtering tank having weep holes along the lower edge draining into an inclined channel for capturing filtered water for reuse, and also includes a multiple layer filter bed containing an upper layer of fine jagged surfaced particles for capturing filtered sludge. The sludge layer deposited on the surface of the upper filter layer is periodically moved by means of an adjustable screed blade toward an elevated discharge station for removal from the tank without significantly disturbing the filter bed. The screed blade may be automatically raised out of contact with the sludge layer when operated in the reverse direction.

Abstract: An adsorbtion filter for water including a housing containing a plurality of layers of granules of different types of activated carbon material with the carbon material of a respective layer having substantially the same mesh size, apparent density and adsorbtive capacity, the layers being juxtaposed and the materials of the respective layers having decreasing internal pore size and increasing indices of retentivity proceeding in a direction from the inlet to the outlet of the filter.

Abstract: An upwash, upflow, graded sand filter has a reusable imperforate diaphragm on the top of the graded filter media and an inlet for pressurized fluid above the diaphragm for inflating the diaphragm against the media during filter stage. The filter housing is flared upwardly and outwardly at selected portions to reduce the velocity of upflowing liquid during wash stage for improved grading of the filter media. A natural foraminous layer may be self-grading at the top of the filter media, allowing a circumferential outlet for filtrate. A layer of fine, dense filter media may also be used to increase the size range of media particles in the filter. Special diaphragms may be composed of individual leaflets that float above a dirty-liquid outlet during wash stage, but that sink due to a change in density when the filter is pressurized for filter stage.

Abstract: A coil type filter for diversified applications comprises a spiral wound coil having an inlet and an outlet at opposite ends thereof, said inlet and outlet apertures having a screen positioned to retain the filtering element within the coil. Couplings are provided on the exterior of the coil at each end for connection to other portions of a fluid flow system. The interior of the coil is partially filled with activated carbon granules which perform the filtering operation. In a modification of the invention, the coil would be positioned within a housing which contains a circulating fluid for maintaining the temperature at predetermined levels. In another embodiment of the invention, the spiral wound coil is mounted within a housing with the inlet and outlet both extending outwardly from the same portion of the housing. The filter outlet is a substantially straight tube extending from the interior end portion of the coil substantially parallel to the axis of said coil and along its entire length.

Abstract: A filtering device for cleansing oil mist from an effluent flow includes a hollow casing containing a filtering media of packed particulate solids and channel means projecting into the media adapted to conduct an effluent flow to the media and disperse it therethrough whereby oil mist particles are retained in the media while the cleansed flow is admitted to the atmosphere. The particulate solids of the filtering media are of a material having an affinity for attracting and retaining oil and the material is disposed in successive layers such that the effluent must pass through a bed of graduated density whereby the filtering efficiency is enhanced.

Abstract: A bath water treating system in which even higly resistant germs may be destroyed by treating the bath water with ozone and a halogen compound such as bromine or hydrobromic acid to establish a redox potential in excess of 600 mV. The bath water is recycled through a quartz type filter loaded with a composite filtering medium. The filtering medium comprises two superposed layers, a lower layer consisting of a mixture of filter gravel and mineralized charcoal, and an upper layer of activated charcoal. A halogen or halogen compound is adsorbed in the charcoal layer. An ozone generator is mounted within the filter housing. The bath-tub assembly comprises a cabinet in which are mounted a bath-tub, a filtering and degerminating unit and the respective accessories and controls. The ozonizer is removably mounted within the filter housing and includes a mixing chamber and check valves.

Abstract: Placed in the ground adjacent a conventional septic tank are a purification tank, which contains a smaller, cylindrical filter tank, and a plurality of spaced, parallel, vertically-disposed ozonating tanks, which are located in an annular space between the filter tank and the purification tank. Perforated diffusers in the lower ends of the ozonating tanks are connected to an ozone generator which intermittently supplies ozone gas to the diffusers. Liquid effluent from the septic tank is fed to the lower end of the filter tank and passes upwardly through a removable, porous filter, then successively through the ozonating tanks, then into the space or reservoir formed in the purification tank around the outsides of the filter tank and ozonating tanks, and finally through an overflow outlet to a surrounding leach field. Excess ozone gas is piped from the upper ends of the ozonating tanks back to the septic tank to increase the effectiveness of the septic tank.

Abstract: Disclosed herein is a method for cleaning a filter device packed with a bed of filtering grains, which cleaning is effected whenever the pressure loss in the filter device has increased to a prescribed level by first discharging the filtering grains through the upper side of the device in conjunction with a current of water, then circulating the filtering grains back into the device via the lower side thereof and giving the freshly formed bed of filtering grains a backwashing with water.

Abstract: A bed of granular media is supported in a vessel to process liquid flowed in through both the upper and lower faces of the bed and out of the bed at a location intermediate the upper and lower faces. A drain structure for the processed liquid is mounted at the location intermediate the two bed faces with the capacity to withdraw the quantity of liquid flowing into both of the bed faces. A closed circuit is provided to transfer residual material in the drain structure back to the inlet system of the bed after backwash of the bed. A holding vessel is connected to the vessel in which the media bed is supported to temporarily receive the media for service periods of the bed vessel.

Abstract: A method of and apparatus for filtering, including a plurality of separate filter media beds progressively decreasing in granular media size in the direction of filtration flow. One embodiment of the invention includes two separate media beds comprised of two intimately contacting granular layers of different granular size. A second embodiment of the invention includes three separated media beds. In this embodiment the first bed consists of a single media layer and the second and third beds are comprised of two intimately contacting media layers of different granular size. In both embodiments, the filtration flow rate through each successive separate bed is less than that in the immediately preceeding bed.