Abstract: A filter cartridge end-of-life mechanism and a filter cartridge assembly for a water treatment device. The end-of-life mechanism comprises a float which is moved along an escapement path each time the device is filled. A counting mechanism connected to the float provides a continuous visual indication of the amount of useful life remaining in the filter cartridge. The cartridge assembly includes a tray detachably connected to a filter cartridge. The tray is positioned beneath the outlet end of the cartridge to remove water treatment particles from the treated water.

Abstract: An apparatus and methods for sanitizing and cleaning filtration systems is provided. The apparatus includes a chamber fluidly connected to a source of fluid for backwashing the system, and a heat exchanger for increasing the temperature of the fluid. A filter media is positioned within the chamber. The method of sanitization involves backwashing the apparatus to remove debris, then continuing to circulate the backwash fluid through the system while increasing the temperature of the fluid, until the temperature of the water and apparatus is sufficient to deactivate microorganisms. The method may also involve increasing the disinfecting power of the fluid by adjusting the pH of the fluid. The apparatus may be provided with a scavenger to assist in the substantially complete removal of fluid from the chamber during and after a steaming or cleaning process.

Abstract: Apparatus for treating water utilizes a single flow control valve that has only one moving part to divert treated water from several water treatment units to backwash another water treatment unit.

Abstract: A seal stack, configured for supporting, guiding, and sealing a piston of a water softener control valve or the like, can be preassembled prior to its insertion into the associated valve bore and compressed after it is inserted into the bore. This post-assembly seal stack compression assures reliable assembly of the seal stack, facilitates valve assembly and disassembly, and negates the need to hold tight tolerances in bore diameter design and seal diameter design. The seal stack includes a plurality of static seals, a plurality of dynamic seals which are either combined with or separated from the static seals, and a plurality of spacers that support the seals. Each of the static seals is disposed between two adjacent spacers and seals against a peripheral surface of the bore, and each of the dynamic seals is disposed between two adjacent spacers and seals against the piston.

Abstract: A simulated moving bed separation system is provided, in which a fluid circulation flow path can be washed for a short time. This system is provided with a circulation flow path having two or more packed beds connected in series and endlessly to each other, with desorbing-charging inlet, extract draw-out port, feedstock introducing port and raffinate draw-out port arranged in this order in the direction of flow of a circulation liquid, which are allowed to intermittently shift in the direction while being kept in this order, and with packed bed-washing pipes, valves and pumps. A desorbing liquid is introduced through the desorbing liquid introducing port into the circulation flow path. An extract rich in a strongly adsorptive constituent to be separated is drawn out through the extract draw-out port.

Abstract: An improved vertical filtration unit which includes an airlift and a washbox designed for more efficient washing of dirt particles from the filtration material. The washbox consists of a filter media shield, and a washbox skirt for washing of the filtration material. A throttling valve on the wash water discharge line regulates the overall cleaning rate of the unit. The filtered liquid is discharged via a riser pipe which feeds into a filtered liquid box before exiting the filtration unit.

Abstract: The invention relates to a method and device for the continuous filtration of liquids containing solid matter, in particular for cleaning wastewater, by means of a filter bed consisting of a particulate filtering medium, which is continuously moved through a vertically positioned cylindrical annular space (2) through which the liquid to be filtered continuously flows radially from the interior to the exterior. The particulate filtering medium containing the separated solid matter is continuously tapped from the lower end of the annular space (2), transported to the top, freed of the filtered solid matter and fed back into the annular space (2) at its upper end. With this kind of method and device, to be able to prevent in a better and more simple manner blockages caused by the separated floc of solid matter, the invention provides that as particulate filtering medium a particle mixture is used with a particle-size range comprising two or more particle sizes, ranging from coarse (2.5 mm) to fine (0.

Abstract: The present invention relates to a liquid filtering apparatus that includes a vessel which contains a bed of particulate or granular filter medium and a filter-medium washer (7) located above the upper side of the bed. The apparatus includes circulation means (8) for continuously transferring dirtied filter medium from a lower part of the bed to the filter-medium washer (7), and for transferring washed filter medium from the filter-medium washer (7) to an upper part of the bed. The washer (7) includes a wash chamber (19) defined between walls (17, 18) that have at least a vertical extension. Filter medium is moved down through the wash chamber (19) while washing liquid is moved up through said chamber. The inventive apparatus also includes means for adjusting the extension of the wash chamber (19) in the flow direction. The invention also relates to a filtering method of a corresponding kind.

Abstract: A method of regenerating an ion exchange resin, comprising the steps of packing a used ion exchange resin in a regeneration tower; and repeating at least twice a step comprising passing an aqueous solution of regenerant through the regeneration tower downward from a top part of the regeneration tower and thereafter passing ultra-pure water through the regeneration tower upward from a bottom of the regeneration tower. This method enables regenerating an ion exchange resin efficiently and homogeneously without mixing of the regenerant into ion exchange resin towers for purification.

Abstract: An improved water softening process is provided which also reduces anion content. A first stream of water is passed through an anion-exchange unit to remove undesirable anions and raise the pH. The first stream of water is then provided to reactor/clarifier water softening equipment, where it acts as a source of hydroxyl ions. Preferably a second stream of water which did not pass through an anion-exchange unit is also provided to the water softening equipment. The streams of water are combined and processed through the softening equipment, where hardness ions are precipitated out, yielding softened water with reduced anion content. The anion-exchange system utilized preferably has a counter-current continuous resin train and a counter-current continuous resin regeneration unit.

Abstract: Adsorptive separation is performed on liquid media by directing the media containing a target substance through an adsorber stage A whereby the target substance is adsorbed; in the last phase of loading stage A and prior to breakthrough of the target substance in the stage A permeate, the stage A permeate is directed to a second adsorber stage B. Upon completion of the stage A loading, the target substance from stage A is eluted with buffer solution, which buffer solution is introduced to stage B, and liquid medium is directed to the preloaded stage A, while stage A is eluted so as both recover the target substance and regenerate the adsorptive capacity of stage A.

Abstract: Regeneration of water treatment media is disclosed which includes a water treatment unit having one or more media therein, and which upon initiation of flow of the water, imparts turbulence and abrasion to the treatment medium to automatically cleanse the medium of light solid contaminants as well as contaminant coatings on the media. This greatly improves the operation of the media and extends its life. In addition, the water treatment unit disclosed may simply be rotated through any one of a number of positions between service, backwash, flush, off, and/or bypass operational modes for further regeneration of the treatment media.

Abstract: A self-regenerating filter unit having a housing which carries an ultrasonic transducer periodically energizable to dislodge caked solids from a filter element in the housing. The removed solids collect in a storage zone where they are periodically removed.

Abstract: A procedure for reducing the patulin content in a fruit juice which includes presenting the juice to a resin material having in abundance micropores of less than 20 Å minimum pore width and at least a pore surface capable of retaining patulin by the forces of chemisorption. Preferably the resin has weak base functionality and is substantially devoid of mesopores and macropores. The resin preferably has a surface area of greater than 900 m2/g (BET) and the resin has been hypercross-linked whilst in the swollen state. Regeneration involves the conversion of the resin held patulin to a more easily flushed out derivative using ammonia or a volatile base, preferably generated in situ from a high pH solution.

Abstract: Regeneration of water treatment media is disclosed which includes a water treatment unit having one or more media therein, and which upon initiation of flow of the water, imparts turbulence and abrasion to the treatment medium to automatically cleanse the medium of light solid contaminants, as well as contaminant coatings on the media. This greatly improves the operation of the media and extends its life. In addition, the water treatment unit disclosed may simply be rotated through any one of a number of positions between service, backwash, flush, off and/or bypass operational modes for further regeneration of the treatment media.

Abstract: Methods and apparatus for contacting solids and fluids are provided, where the fluids are allowed to traverse a downward path through a plurality of vertically arranged chambers in which said solids are located. The solids may be transferred upwardly through the chambers to assure optimal contact between the solids and the fluids. The transfer of the solids may be accomplished by fluidizing the solids and transporting them in a carrier fluid in a fluid flow loop. At the desired transfer location, the solids are prevented from completing passage through the fluid loop.

Abstract: A water treatment system including a pair of water treatment tanks, each tank defining a flow path extending from a tank inlet to a tank outlet and containing a water treatment material disposed along the flow path for treating water as it travels from the inlet to the outlet. A system controller controls which of the tanks is on-line and which of the tanks is off-line and controls the regeneration of an exhausted tank. The system controller is operative to provide a final rinse in the service direction. This is accomplished by a purge valve which communicates the outlet of a tank being regenerated to a drain under predetermined operating conditions. The operation of the purge valve is responsive to fluid signals applied to an inlet valve and an outlet valve associated with the tank being regenerated. More specifically, the fluid signals that close the outlet valve and open the inlet valve, are utilized to cause the opening of the purge valve in order to communicate the tank outlet with the drain.

Abstract: A method and apparatus for the treatment of wastewater effluent from a laundromat combines multiple filtering, particularly including, bag filters, to remove particulates including fine particulates followed by treatment in a weak base anion exchange resin bed to remove MBAS. The weak base resin was found to remove MBAS and organics such as LAS which were highly de-adsorbed in the efficient regeneration of the resin. The weak base anion exchange resin is preferably macroporous in the sulfate form. The invention contemplates multiple bag filters of different degrees of coarseness.

Abstract: In a water purification system in which a first filter (20) is placed in a flow of raw water for filtering the raw water to produce filtered water, a second filter (27) is placed downstream of the first filter for filtering the filtered water. The first filter is conductive and has a plurality of water passages through which the raw water flows. Each of the water passages of the first filter has a first diameter. At intervals, an electric voltage is applied to the first filter to destroy bacteria which is captured by the first filter. The second filter has a plurality of water passages through which the filtered water flows. Each of the water passages of the second filter has a second diameter smaller than the first diameter.

Abstract: The invention relates to new regenerable filtration adjuvants which are usable for the filtration of liquids, particularly beer at the end of the secondary fermentation storage, characterized in that they comprise synthetic or natural incompressible polymer grains or natural incompressible grains grains having a sphericity coefficient varying between approximately 0.6 and 0.9. The invention also relates to a method for regenerating a filtration adjuvant.

Abstract: Described are preferred processes and apparatuses for thermally desorbing desired chemical products from resins to which they are adsorbed. The processes and apparatuses provide highly efficient use of applied heat throughout resin preheat, desorption and cooling phases.

Abstract: A septic system and method for the removal of nitrogen contaminants, such as nitrates and ammonia, from a wastewater effluent, which system and method includes employing one or more zeolite tanks, which contains a regenerable, granulated zeolite material to receive wastewater effluent from a septic tank, and to capture the nitrogen contaminants, such as nitrate and ammonia, and retain the nitrogen contaminants in the zeolite material allowing the treated, decontaminated effluent to flow out of the tank into a leach field. The system and method includes for periodically regenerating the zeolite material in the zeolite tank, after the zeolite material has become substantially exhausted, and restoring the zeolite material in the zeolite tank for reuse. The system provides for removal of the displaced nitrogen contaminants generated from the regeneration of the zeolite material in the zeolite tank.

Abstract: Regeneration of water treatment media is disclosed which includes a water treatment unit having one or more media therein, and which upon initiation of flow of the water, imparts turbulence and abrasion to the treatment medium to automatically cleanse the medium of light solid contaminants, as well as contaminant coatings on the media. This greatly improves the operation of the media and extends its life. In addition, the water treatment unit disclosed may simply be rotated through any one of a number of positions between service, backwash, flush, off, and/or bypass operational modes for further regeneration of the treatment media.

Abstract: An apparatus for generating high purity acid or base in an aqueous stream for use as an eluent for chromatography and, particularly, ion chromatography. For generating a base for anion chromatography, the aqueous stream is directed through a cation exchange bed. An electrical potential is applied to the bed. Cations on the bed electromigrate into the aqueous stream while hydroxide ions are electrolytically generated to form a base-containing eluent. Anions to be detected and the generated eluent flow through a chromatographic separator and a detector. In one embodiment, between separation and detection, the separated anion stream flows through a second cation exchange bed with no electrical potential applied. The second bed serves as a suppressor. After completion of the desired number of cycles, flow through the first and second cation exchange beds may be reversed by appropriate valving for the next sample stream.

Abstract: In a dispensing apparatus having a water purification unit for purifying raw water to produce purified water, a beverage unit for producing the beverage by the use of the purified water, and a pipeline for conducting the purified water from the water purification unit to the beverage unit, a flow rate detector is connected to the pipeline. The flow rate detector detects a flow rate of the purified water in the pipeline to produce a flow rate signal. Responsive to the flow rate signal, a control arrangement controls supply of the raw water into the water purification unit.

Abstract: Treatment of sewage water contaminated by phosphorus is accomplished by passing the water through iron oxide. The iron oxide is placed in close proximity to soft resilient open-cell foam, which serves to slow down, and even out, the rate of travel of the water while under treatment, thus increasing the residence time.

Abstract: The invention relates to separating different substances, more concretely, to a method and apparatus for filters, degassing, dehydrating and removing products of ageing in insulating and other petroleum oils. The technical result is that the aforesaid phases of processing oil or a mixture of oils are ensured with high efficiency for a single passage through an active component, and also the possibility of regenerating the adsorbents being used is ensured during the process of operation of the equipment, with simultaneous simplification of the construction and reduction of size and of power consumption. The apparatus 1 for filtering, degassing, dehydrating and removing products of ageing comprises at least one tank 2, in which are disposed cylindrical partitions 3, 4 filled with an adsorbent 5 and secured in the tank 2 by means of fixing elements 6. Partitions 3, 4 form channels for the passage of oil being processed.

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: A conical intake screen which is self-cleaned by using four elongate brushes which are slowly driven over its surface by a submersible, programmable electric motor. The invention is preferably placed in the waterway with the axis of the conical screen oriented in the vertical direction. As the rearwardly angled brushes move over the screen, the brush angle and gravity tend to force the debris downward until it falls from the edge of the device. Further, a cleaning brush is placed within the surface of the conical screen with its bristles extending slightly above the surface of the screen. In this manner each screen sweeper engages the brush cleaner once each rotation, which action tends to dislodge debris from the bristles of the sweeper brushes. The programmable motor will typically make three counterclockwise revolutions, one clockwise revolution, and then stop for a selectable interval of from 15 minutes to 3 hours, although continuous action is also an option.

Abstract: Ions (e.g. lithium) can be removed or recovered from brines containing those ions and optionally one or more other ions (e.g. other alkali metal ions) by the use of a temperature-swing, ion-exchange process and apparatus employing an ion-exchange material. The process and apparatus depends on a change in the selectivity coefficient of an ion exchange material for the ions desired to be recovered with a change in temperature, resulting in desirable ions being relatively selectively released at one temperature and undesirable ions being relatively selectively released at another temperature. The process of the invention can be used to effect the separation of any ion (or set of ions) from another ion or from a set of ions wherein the selectivity coefficient for one ion (or set of ions) has a substantial temperature dependence, compared to that for the other ion (or set of ions).

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: A water treating apparatus is provided which can treat waste water for use as raw water in an ultrapure water producing system without addition of various kinds of chemicals. The apparatus includes a first water tank for receiving acid waste water, a second water tank for subjecting the waste water from the first water tank to solid-liquid separation and discharging supernatant liquid, an ion exchange tank including ion exchange resin and an aeration tube for generating treated water through a membrane filter, a precipitation tank for settling ion exchange resin, an air lift pump for introducing ion exchange resin from the precipitation tank into the first water tank, and a return air lift pump for returning ion exchange resin from the second water tank to the ion exchange tank. The ion exchange resin acts to exchange ions with fluorine ions of treated water in the ion exchange tank and is regenerated by acid waste water in the first water tank.

Abstract: A structure for the absorption or desorption of a substance on a bed through which liquid is allowed to pass comprises a vessel containing a liquid-permeable bed, a lower adaptor, an upper adaptor and means for providing a liquid flow to the bed through one of the adaptors and means for conducting a liquid flow away from the bed through the other adaptor. The lower adaptor is arranged in the lower part of the vessel and at least partially defines the vessel bottom. The lower adaptor has an opening for the passage of liquid to or from the lower part of the vessel, which opening is directed toward the bed, and the lower adaptor is provided with a distribution facility for distributing or collecting liquid flow towards or from, respectively, a bottom surface of the bed. The upper adaptor is arranged in an upper part of the vessel and at least partially covers a cross-sectional area of the vessel.

Abstract: A suspension is delivered to a filter bed comprised of granular filter medium in a continuously working filter at the lower part of the bed and is then permitted to flow upwards through the bed. With the intention of optimizing the capacity of the filter, the suspension is now guided into a central region of the bed. The suspension is divided from this region into at least two specific proportional quantities which are each led from the filter bed in a respective ring-shaped pattern at mutually different heights in relation to the extension of the bed, these ring-shaped patterns having different diameters and each being adapted to the extension of the filter medium in the direction of the diameter.

Abstract: An apparatus for continuously separating ion exchange resin particles with upwardly flowing carrier fluid. The apparatus includes a first vertically oriented separation vessel and a first collection vessel for receiving the first fraction of resin particles from the upper zone of the first separation vessel. A first rejuvenation tank is connected to the first collection vessel for receiving the first fraction of resin particles from the first collection vessel. In the preferred embodiment, the apparatus further includes a second vertically oriented separation vessel and a second collection vessel for receiving the first sub-fraction of the second fraction of resin particles from the upper zone of the second separation vessel.

Abstract: A water treating apparatus is provided which can treat waste water for use as raw water in an ultrapure water producing system without addition of various kinds of chemicals. The apparatus includes a first water tank for receiving acid waste water, a second water tank for subjecting the waste water from the first water tank to solid-liquid separation and discharging supernatant liquid, an ion exchange tank including ion exchange resin and an aeration tube for generating treated water through a membrane filter, a precipitation tank for settling ion exchange resin, an air lift pump for introducing ion exchange resin from the precipitation tank into the first water tank, and a return air lift pump for returning ion exchange resin from the second water tank to the ion exchange tank. The ion exchange resin acts to exchange ions with fluorine ions of treated water in the ion exchange tank and is regenerated by acid waste water in the first water tank.

Abstract: It is possible to filter a suspension or emulsion in a filter bed of particulate filter medium by allowing the suspension to flow upwards through the filter bed simultaneously as the medium flows downwards through a filtering tank wherein filtration takes place. Filtration thus takes place during counterflow between suspension and filter medium. The supply of suspension takes place in the lower part of the filter bed and the filtered liquid phase is taken away from a zone above the filter bed. The polluted filter medium close to the bottom of the filter tank is taken out for conveyance to a washing apparatus above the filter bed and after washing is returned to the upper side of the filter bed. For providing a filter which has a considerably lower construction height for a given and unchanged volume of the filter medium, the washing apparatus is lowered so that its lower part is at a level below the upper surface of the filter bed.

Abstract: A water softening device includes a cylindrical housing with an inlet formed at one end for admitting water to be treated. A filtering material is located in an upstream zone adjacent the inlet. A plate is positioned in relative spaced relation to an opposite end of the housing. A downstream zone, free of filtering material, is located between the plate and the opposite end. Openings are formed in the plate to allow passage of softened water to flow between the upstream and downstream zones. A conduit is axially located in the housing and has a first open end communicating with the downstream zone. A second end of the conduit forms an outlet of the device. A check valve is located at the first end of the conduit for allowing unidirectional flow of water undergoing softening from the downstream zone to the conduit, the check valve restricting flow between the zones during brine regeneration.

Abstract: An automatic device for the regeneration of a bed of ion-exchanging resins s constituted by a valve body internally provided with two communicating seats, in whose inside pistons which are caused to move by a couple of cams keyed on a motor-shaft slide. The valve body is provided with openings, alternately intercepted by the pistons, to realize different flows of the fluid. In running conditions, water passes through a tank containing a bed of ion-exchanging resins, whose regeneration takes place in counter-current with solutions of sodium salts. This operating stage and the following one of resin washing are carried out according to an automatic sequence by way of cams, which act on the piston.

Abstract: A system is provided for removing impurities anticipated to be found in industrial waste water, which system is particularly well suited for waste water systems such as those used for laundry or vehicle washing operations. The system includes aeration, mixing/flocculating, and contact media mechanisms to remove suspended solids, hydrocarbons, organic materials and undesired dissolved minerals from the treated water.

Abstract: A method and apparatus for regenerating an ion exchange resin utilizing recycled solution or reused regeneration solution. At least one tank containing an ion exchange material is provided having a spaced first and second ports which define a fluid flow path through the ion exchange media. Water to be treated is introduced at an inlet and flows through the resin bed ultimately being discharged at the outlet. A polishing zone is located at the outlet which includes highly regenerated, uncontaminated resin. The media is regenerated in a multi-step process in which regeneration solution is introduced into the resin bed in two separate steps. In the first step, a first regeneration solution is introduced into the resin bed upstream from the polishing zone, flows in a countercurrent direction and is discharged through the inlet of the tank. A second regeneration fluid is introduced at the outlet of the tank and flows in a countercurrent direction through the entire resin bed.

Abstract: Method and apparatus by which contaminants are removed from a liquid flowing through a filter vessel having an inlet for providing a contaminated liquid flow into one end thereof and an outlet through which filtered liquid can exit the vessel. A filter screen supports a relatively large quantity of particulate filter media within the filter vessel on the filter screen for normal filter operation and captures contaminants by flowing contaminated liquid through the inlet while filtered liquid exits through the filter screen and outlet, leaving the contaminants on the filter media. The system automatically occasionally cleans the media in a unique cleaning cycle, that includes one or a plurality of closed loop flow paths that fluidizes the media within one filter vessel and cleans the media externally of the filter vessel by flowing the fluidized filter media along the closed loop flow path.

Abstract: Disclosed is a novel continuous ion exchange apparatus capable of performing both ion exchange treatment and regeneration treatment within a single column by the use of ion exchange resin(s) whose ion exchange abilities can be regenerated by acid or alkali.

Abstract: A system automated for providing at least periodic removal of metal ions and contaminants from a chemical bath, consists of a microprocessor programmed for controlling fluid circuits of pumps and valves, for in one state of operation circulating a first predetermined quantity of the chemical bath from a first tank, through an ion exchange column, and back to the first tank; for in a second state of operation circulating deionized water from a second tank into the IEX column for displacing residual chemical bath therefrom for return to the first tank; for in a third state of operation circulating deionized water through the IEX column, and discharging the rinse water from a waste port; for in a fourth state of operation circulating regenerant acid through the ion exchange column, and discharging the used acid from a waste port; for in a fifth state of operation circulating deionized water through the IEX column for rinsing acid regenerant therefrom and discharging the same out of a waste port; and for in a six

Abstract: A filter system (110) includes a tank (130) with a conveyer (140) for, preferably continuously, conveying filter media (11) from a filter zone (119) in the tank (130) where the filter media (11) traps predetermined matter (16), such as particulates, to a quiet zone (115) in the tank (130) where the predetermined matter (16) separates from the filter media (11) and is allowed to accumulate and be withdrawn from the tank (130). The conveyer (140) preferably includes a screw auger (141) and a duct (142) for containing the screw auger (141). The filter media (11) is preferably buoyant when the fluid (21) being filtered is water.

Abstract: A system automated for providing at least periodic removal of metal ions and contaminants from a chemical bath, consists of a microprocessor programmed for controlling fluid circuits of pumps and valves, for in one state of operation circulating a first predetermined quantity of the chemical bath from a first tank, through an ion exchange column, and back to the first tank; for in a second state of operation circulating deigned water from a second tank into the IEX column for displacing residual chemical bath therefrom for return to the first tank; for in a third state of operation circulating deigned water through the IEX column, and discharging the rinse water from a waste port; for in a fourth state of operation circulating regenerate acid through the ion exchange column, and discharging the used acid from a waste port; for in a fifth state of operation circulating deionized water through the IEX column for rinsing acid regenerate therefrom and discharging the same out of a waste port; and for in a sixth s

Abstract: New methods are disclosed for improving the cleansing the plurality of seriate filter beds in automatic backwash filtering systems, equipped with a traveling backwash shoe, in which the beds are backwashed one at a time with backwash liquid from an effluent channel common to seriate effluent ports of the plurality of filter beds by pumping the backwash liquid seriatim through separate effluent ports of individual filter beds and then flowing filtered effluent from each bed through its effluent port into the effluent channel, repeating such steps of backwashing and flowing filtered effluent on individual filter beds until all the filter beds in the system have been backwashed, wherein, simultaneously with the backwashing of such active bed, the bed forward in the direction of travel of the backwash shoe is subjected to a prewash with chemical treatment liquid by pumping such liquid upwardly in such forward bed through its effluent port. Apparatus for carrying out the improved methods is also disclosed.

Abstract: A deep bed filter system comprising a plurality of filter media beds, each having a respective media regeneration sub-system that includes some components associated with an individual filter bed and other components that are shared with all filter beds in the system, thereby improving the utilization of available space and lowering the materials and labor costs relative to known systems. A central column extends upwardly along the axis through the upper and lower portions of the vessel, thereby defining an annular volume extending substantially from the bottom of the vessel through the upper and lower portions. A plurality of distinct tubes extend through the central column, with each tube having a lower, intake end situated at the bottom for drawing dirtied filter media from the lower portion of the vessel into the column and transporting the drawn media upwardly through the column to a second discharge end at an elevation above the filtrate level of the filtrate region.

Abstract: The invention is a demineralization apparatus comprising an anode chamber disposed at one end of a vessel having an anode at the inside of the anode chamber. A cathode chamber is disposed at the other end of the vessel, having a cathode at the inside of the cathode chamber. At lease one diluting chamber and at least one concentrating chamber are located alternately between the anode chamber and the cathode chamber. The diluting chamber has an anion exchange membrane on the anode chamber side and a cation exchange membrane on the cathode chamber side. The diluting chamber has an inlet for water to be treated and an outlet for demineralized water. The concentrating chamber has an inlet for water and an outlet for ion-concentrated water. The diluting chamber contains a cloth comprising a mixture of strongly acidic cation exchange fibers, strongly basic anion exchange fibers and ionically inactive synthetic fibers. Preferably, the mixture contains from 20 to 70% by weight ionically inactive synthetic fibers.

Abstract: A method of cleaning a filtration tank having a plurality of side-by-side gravity flow filter cells, each having an outlet port in communication with a filtrate channel common to all of the cells in an automatic backwash/rewash system, by subjecting each compartment, sequentially, to a backwashing operation and then a rewashing operation wherein, during backwashing, backwash liquid is pumped through a first of the filter chamber ports to flow upwardly through a first of the compartments in a direction opposite to a normal filtration flow direction, and during rewashing, rewash liquid is drawn downwardly through the first cell in the normal filtration flow direction. For any given cell after a first of the plurality of cells, utilizing at least a portion of the rewash liquid from a rearwardly adjacent filter cell is used as backwash liquid in the given cell.