Abstract: A media filter includes an inlet and a diffuser located axially below the inlet for distributing liquid entering the filter via the inlet over the media in the filter. The diffuser including one or more members extending generally orthogonal to the axis of the filter.

Abstract: A composite filter apparatus includes a container with a receiving space, and top and bottom openings communicated with the receiving space. A filter member includes a filter core in the receiving space, a blocking member on a top end of the filter core, and a retainer plate on a bottom end of the filter core. The receiving space is divided by the blocking member into an upper receiving space that communicates the top opening of the container, and a lower receiving space that surrounds the filter core and that communicates the bottom opening. Activated carbon particles are filled in the upper and lower receiving spaces.

Abstract: A method and system for fluid treatment that provides fluid release cycles within the regeneration sequence of a fluid treatment device. The fluid release or backwash air cycle permits the slow, controlled and metered release of air or gases from a treatment tank.

Abstract: An apparatus for treating a liquid containing impurities may comprise: a filtering chamber for receiving liquid containing impurities, the filtering chamber containing granular media and configured to permit the granular media to interact with the liquid containing impurities, thereby removing impurities from the liquid to produce filtrate; a filtrate section in communication with the filtering chamber for receiving the filtrate, the filtrate section being in communication with a first outlet for outflow of the filtrate; a gas supplying system for delivering gas to the granular media in the filtering chamber for transport of a portion of the granular media to a granular media washer; and a reject section in communication with the granular media washer for receiving a reject mixture comprising liquid and impurities from the granular media washer. The reject section may be in communication with a second outlet for outflow of a portion of the reject mixture.

Abstract: An apparatus for treating a liquid containing impurities may comprise: a filtering chamber for receiving liquid containing impurities, the filtering chamber containing granular media and configured to permit the granular media to interact with the liquid containing impurities, thereby removing impurities from the liquid to produce filtrate; a filtrate section in communication with the filtering chamber for receiving the filtrate, the filtrate section being in communication with a first outlet for outflow of the filtrate; a gas supplying system for delivering gas to the granular media in the filtering chamber for transport of a portion of the granular media to a granular media washer; and a reject section in communication with the granular media washer for receiving a reject mixture comprising liquid and impurities from the granular media washer. The reject section may be in communication with a second outlet for outflow of a portion of the reject mixture.

Abstract: The present invention relates to a water filter device having a filter head with filter head components, a replaceable filter candle with filter candle components, and an encoding structure which is formed between a filter head component and a filter candle component. The water filter device is distinguished, in a first embodiment, in that an encoding structure is formed with axial orientation on an end face of the filter candle and/or on an element which is associated with such an end face of the filter candle. In a second embodiment, said water filter device is distinguished in that an encoding structure is formed separately from a fixing structure.

Abstract: According to one embodiment, in order to eliminate impurities, and the like, water to be treated is passed through each of reactor vessels, phosphorus contained in the water to be treated is removed by using an adsorbent, and thereafter the liquid held in each of the reactor vessels is discharged through each of first to third treated water discharge paths, thereby eliminating the impurities, and the like derived from the water to be treated. It is possible to eliminate the influence of the impurities in the water to be treated on the discharged desorption agent liquid containing phosphorus from the phosphorus adsorbent can be eliminated, and hence it is possible to obtain a phosphorus-containing liquid containing no substance other than the recovered phosphoric matter material.

Abstract: A syphon filtration system is a low head, small foot print, long operating cycle, gravity filtration system for treatment of water and wastewater, with one-stage or two-stage filtration in one vessel with different filtration media of sand, anthracite, granular activated carbon or other proprietary filtration media. The one-stage filtration system removes suspended solids or dissolved impurities and the two-stage filtration system removes suspended solids and dissolved impurities. In the two-stage filtration system, each filtration stage can be backwashed independently or both stages can be backwashed simultaneously. Novel syphon piping and controls design extend the filtration operating cycle and reduce the filter apparatus headroom, and the filter backwash water volume requirements.

Abstract: Exemplary systems and methods relating to washboxes are described.

Abstract: Exemplary systems and methods relating to washboxes are described.

Abstract: The disclosed invention is a fixed bed ion exchange water purification system. It employs a combination of electronically controlled process steps and specific systems configurations to duplicate the effects of moving resin beds from one operating position to another as is required in moving bed ion exchange water purification systems. The invention combines features of single fixed bed ion exchange systems with those of a moving bed system. The invention applies to the treatment of water having typical industrial and drinking water concentrations of various ions.

Abstract: Filtration of water to provide cleansed water, using an assembly that monitors the volume of water cleansed and back-flushes the filtration media based on that volume. The assembly includes a control valve that monitors the amount of water that has been processed, controls the addition of water and oxygen to the assembly, and thus affects the overall operation of the assembly.

Abstract: The disclosed invention is a fixed bed ion exchange water purification system. It employs a combination of electronically controlled process steps and specific systems configurations to duplicate the effects of moving resin beds from one operating position to another as is required in moving bed ion exchange water purification systems. The invention combines features of single fixed bed ion exchange systems with those of a moving bed system. The invention applies to the treatment of water having typical industrial and drinking water concentrations of various ions.

Abstract: The present invention provides a method for selectively removing metal ions of interest from a solution (12), such as the wastewater from a chemical mechanical polishing process. The method comprises contacting a solution (12) containing solid particles, an oxidizing agent and a first concentration of the metal ions with an ion-exchange resin (20), such as a crosslinked poly-4-vinylpyridine resin, that is resistant to damage by the oxidizing agent and that is operative when in contact with the solution (12) to exchange selected ones of the metal ions in the solution for selected preferred ions in the ion-exchange resin thereby to produce a treated solution (22) having a second concentration of the metal ions that is lower than the first concentration. The present invention also relates to an apparatus (100) and system (500) for use with the method of the present invention.

Abstract: Presented is a liquid filtering apparatus and method that overcomes the disadvantages encountered with prior bed filtration systems by providing a filtering apparatus that incorporates a super-buoyant filter medium having a specific gravity very substantially lower than that of the process liquid being filtered. This feature enables a majority of the medium to float on top of the process liquid. Due to the significant differences in specific gravity between the media and the process liquid, super-buoyant media produce a highly advantageous means of naturally, gravimetrically separating both clean and contaminated filter media and process liquid into separate “phases”. Under normal filtering operation, the filter media is contained within a filter housing by a bed support near the top of the filter housing, and particulate material is filtered from a process liquid that passes through the housing.

Abstract: An oxidation filtration system for cleaning groundwater, the system having an aeration tower and a filtration tank. Within the filtration tank is an upper chamber and a lower chamber. Contained within the lower chamber is a plurality of Styrofoam™ filter media. Separating the upper chamber from lower chamber is a filter media mash which keeps the filter media from entering into the upper chamber. The aerated water from the aeration tower enters into the base of the lower filter chamber and rises through the filter media into the upper filter chamber. As the water passes through the filter media, the dissolved solvents fallout of the groundwater and attach themselves to the Styrofoam™ media. An automated back flushing and clarifying process is also provided using a back flush port and a clarification port, a higher level water sensor in the aeration tower and a programmable logic controller.

Abstract: The apparatus and methods of the present invention enable efficient and appropriate treatment of Urban Water Runoff, so that the treated Urban water Runoff can be can be introduced into public waterways without contaminating such waterways. The system apparatus utilizes adsorptive Organoclay media, mechanical filtration and ultraviolet sterilization. The methods and apparatus of the present invention remove contaminants from Urban Water Runoff to a level which enable the resulting effluent to meet appropriate standards for introducing the treated Urban water Runoff in to public waterways. The method and apparatus of water treatment of the present invention does not utilize chlorine containing compounds which, when combined with organic compounds can produce THM's that can become problematic when re-introduced to the downstream environment. The systems of the present invention can be made sufficiently compact so as to enable their use in remote locations.

Abstract: The disclosed invention is a fixed bed ion exchange system from removing arsenic from water. It employs a combination of electronically controlled process steps and specific systems configurations to duplicate the effects of moving resin beds from one operating position to another as is required in moving bed ion exchange water purification systems. The invention combines features of single fixed bed ion exchange systems with those of a moving bed system.

Abstract: A liquid filtering apparatus which incorporates a filter bed medium having a specific gravity lower than that of the process liquid being filtered. Process liquid is pumped through one or more filter chambers containing the filter bed medium. A discharge line at the top of the housing directs the filtered liquid either back into a process liquid tank or stream, or into a clean liquid storage tank. A small storage tank provides a volume of filtered liquid for use in backwashing the filter bed medium. The particle size and nature of the filter bed medium are determined by the identity and specific gravity of the process liquid to be filtered so that the filter bed is buoyant on the process liquid. As the process liquid is pumped into the filter chamber, the composite filter bed floats to the top of the chamber where it stops rising. The process liquid then passes through the filter bed and the particulates are strained from the liquid by surface filtration and depth filtration.

Abstract: A pipe gallery includes an exterior peripheral wall containing a gallery upper chamber, a backwash waste chamber, and a gallery lower chamber. A gallery influent line and filter influent pipes are connected to the gallery upper chamber. A backwash drain line and secondary pipes are connected to the backwash waste chamber. Filter effluent pipes and a gallery effluent line are connected to the gallery lower chamber. The lower chamber may also include a separate supply chamber, to which a gallery backwash supply line and filter backwash pipes are connected. The filter influent pipes and secondary pipes may be connected to the top chambers of filter cells in a filtration system, while the filter effluent pipes are connected to bottom chambers of the cells. Valves are used to create separate filtering and backwash pathways.

Abstract: A pipe gallery includes an exterior peripheral wall containing a gallery upper chamber, a backwash waste chamber, and a gallery lower chamber. A gallery influent line and filter influent pipes are connected to the gallery upper chamber. A backwash drain line and secondary pipes are connected to the backwash waste chamber. Filter effluent pipes and a gallery effluent line are connected to the gallery lower chamber. The lower chamber may also include a separate supply chamber, to which a gallery backwash supply line and filter backwash pipes are connected. The filter influent pipes and secondary pipes may be connected to the top chambers of filter cells in a filtration system, while the filter effluent pipes are connected to bottom chambers of the cells. Valves are used to create separate filtering and backwash pathways.

Abstract: The disclosed invention is a fixed bed ion exchange system from removing arsenic from water. It employs a combination of electronically controlled process steps and specific systems configurations to duplicate the effects of moving resin beds from one operating position to another as is required in moving bed ion exchange water purification systems. The invention combines features of single fixed bed ion exchange systems with those of a moving bed system.

Abstract: A filtration system for filtering particulate matter from a liquid, the filtration system comprises a pre-filtration apparatus and a main filtration apparatus. The pre-filtration apparatus comprises a vessel having a fluid inlet, a fluid outlet, and a back-washing outlet, and a filtering medium disposed in the vessel and capable of filtering large particulate matter from the liquid and passing fine particulate matter. The fluid inlet and the fluid outlet are positioned such that liquid flowing therebetween is passed through the filtering medium. The fluid outlet and back-washing outlet are positioned such that liquid flowing therebetween is passed through the filtering medium. The main filtration apparatus comprises a vessel having a fluid inlet, a fluid outlet, and a filtering medium disposed in the vessel and capable of filtering fine particulate matter from the liquid. The fluid inlet and the fluid outlet are positioned such that liquid flowing therebetween is passed through the filtering medium.

Abstract: A filter element assembly (10) has at least two cylindrically-shaped and concentrically-arranged filter media sleeves (11, 12), each connected at one end thereof to an inlet plate (13) and each connected at the other end to a terminal plate (20). Openings (16) are provided in the inlet plate to permit entry of liquid to be filtered into the annular space between the filter sleeves. The terminal plate is closed to prevent the flow of unfiltered liquid from the annular space between the sleeves and to force the liquid through the porous media of the sleeves to effect filtration. The ends of the filter sleeves are ultrasonically welded to flanges extending from the plates.

Abstract: An apparatus for filtering contaminated fluids is provided. In a filtering mode, contaminated fluid is introduced into a vessel housing a bed of positively buoyant particulate material and a bed of negatively buoyant particulate material in a spaced apart relationship. The contaminated fluid is passed through the bed of negatively buoyant particulate and through the bed of positively buoyant particulate. In a backwashing mode, a backwashing fluid is passed through the bed of positively buoyant particulate to flush particulate contaminants therefrom. The backwashing fluid is discharged from the vessel at a location between the bed of negatively buoyant particulate and the bed of positively buoyant particulate.

Abstract: A control valve for a fluid treatment system, such as a water softener or a water filter, includes a manifold which mounts a pair of open-ended, cylindrical valve bodies having ports in fluid communication with passages in the manifold. Interchangeable single and double poppet valve assemblies are received into the open ends of the valve body. The poppet valve assemblies have diaphragm valve actuators disposed between chambers that are in fluid communication with selective ones of an array of pilot valves that are also mounted on the manifold. The valve assemblies may be piloted to one position by a spring. A tank adapter connects the manifold to a treatment tank. The tank adapter can be connected to the manifold in two alternate alignments which connect passages in the manifold to the top and bottom of the treatment tank so that co-current or countercurrent flow of regenerative fluid and the fluid to be treated can be alternately selected.

Abstract: A filter media washing system for washing contaminants from filter media of a plurality of filtration vessels. Each filtration vessel has a filtration screen subdividing the filtration vessel into a filter media containing chamber and a filter media-free chamber. Each filter media containing chamber of each filtration vessel has a first fluid passage connected thereto and is located distally from the filtration screen. A second fluid passage is also positioned in each filter media containing chamber, but it is located proximate to the filtration screen. The first and second fluid passages are fluidly coupled, one to the other with a decontamination unit located fluidly therebetween for separating filter media from contamination carried therewith. The decontamination unit includes a contamination separating pump, a contamination separating chamber, a contamination separating screen and a return manifold. The return manifold has a first and second return conduit.

Abstract: A grey water recovery system comprises a filter tank having a filter medium therein. Grey water is delivered to the filter tank by a delivery conduit and filtered grey water is collected in a sump which surrounds the filter tank. A pump removes the filtrate to a distribution system for irrigation and similar use. The recovery system includes a backwash system. The backwash system has a flow responsive poppet valve which permits clean backwashing water and pressurized air to flow upwardly through the filter medium while closing the normal filtrate flow path to the sump.

Abstract: A simplified single cell apparatus and method for removal of suspended impurities in liquids using gas flotation and filtration is provided wherein the method and apparatus are preferably directed to induced gas flotation separation of suspended impurities in combination with a filter media for filtration removal of remaining suspended impurities. A filter media is contained within the single cell apparatus such that liquid exiting the vessel must pass through the filter media after having been subjected to flotation treatment.

Abstract: A simplified single cell apparatus and method for removal of suspended impurities in liquids using gas flotation and filtration is provided wherein the method and apparatus are preferably directed to induced gas flotation separation of suspended impurities in combination with a filter media for filtration removal of remaining suspended impurities. A filter media is contained within the single cell apparatus such that liquid exiting the vessel must pass through the filter media after having been subjected to flotation treatment.

Abstract: A filter for removal of biochemical oxygen demand and suspended solids utilizing multi-layer filtration media. The filter media includes plastic particles, sand, and garnet and is operated under an automatic control condition. Fine filtering is accomplished by a sludge cake which develops at the upstream face of the filter media. For cleaning the filtration media, deposited sludge is removed from the filter bed by backwashing in a short time period at a high strength backwash flow rate.

Abstract: A floating media biofilter is provided, comprising a tank having a bottom and a sidewall, the sidewall having a lower portion inwardly sloping toward the bottom. Floating media are present in the tank for forming a media pack when the tank is filled with liquid, and the media are retained by an upper screen positioned in the upper portion of the tank. An inlet line provides nonfiltered liquid to the tank from an aquaculture environment, while an outlet line above the upper screen delivers filtered liquid back to the aquaculture environment. A weir is employed between the upper screen and the outlet line to collect filtered liquid from the media pack. Backwashing is accomplished by a motorized blade system which causes the media to circulate within the tank with substantially no expansion of the media pack. The circulating media loosens filtered matter and sludge entrained therein so that the waste solids can be removed by a sludge line connected to the bottom of the tank.

Abstract: In a retardation installation having a container holding the adsorber material capable of accepting acid, in particular adsorber resin, and a feed for a watery acid-salt-solution, for example from an anodizing bath, a further feed for a regenerating solution to regenerate the adsorber material, in particular demineralized Water in opposite flow to the acid-salt-solution, as well as a drain for the treated acid-salt-solution which has passed the adsorber material and with at least one pump for the transport of the acid salt solution and/or the regenerating solution, precisely one pump is provided for which is configured as a compressed air-diaphragm pump and which exhibits a device for stroke counting as well as a device for the control of the volume flow of acid-salt-solution or regenerating solution on the a basis of the stroke count of the compressed air-diaphragm pump.

Abstract: A filter for removal of biochemical oxygen demand and suspended solids utilizing multi-layer filtration media. The filter media includes plastic particles, sand, and garnet and is operated under an automatic control condition. Fine filtering is accomplished by a sludge cake which develops at the upstream face of the filter media. For cleaning the filtration media, deposited sludge is removed from the filter bed by backwashing in a short time period at a high strength backwash flow rate.

Abstract: A process for the treatment of water using a granular bed (3) of granular support materials of a volumic mass less than that of the water to be treated. According to this process, each washing cycle comprises interrupting the withdrawal of treated water and stopping the feed of water to be treated in such a manner that the granular bed (3) floats in a given volume VL of water, admitting cleansing air into the reactor for assuring agitation of the floating bed, interrupting the admission of air in order to permit a separation of the granular materials and sediment by their difference in volumic mass, with decantation of said sediment and flotation of said materials, and evacuating the sediments at the base of the reactor as well as the water contained therein for evacuating the granular bed (3).

Abstract: The well water removal and treatment system of the present invention includes a pumping and well water withdrawl loop consisting of an above ground pump, a pressurized water drive line from the pump outlet to a well water ejector, a water return line from the well water ejector to an aeration and precipitation tank, an inlet line from the aeration and precipitation tank to the pump and a venturi nozzle air mixing manifold fluidically connected between the high pressure drive water line and the lower pressure water delivery line to mix air into the water during the entire pump cycle. The water delivery line from the pumping and withdrawal loop has a flow control regulator therein that controls the water flow therethrough in proportion to the water pressure in the pumping and withdrawal loop above a preselected minimum control level.

Abstract: The filtration system provides a long horizontal flow path through buoyant filter media. The filter media is contained in a vessel and the relationship between the water level in the vessel and the amount of filter media is such that the media extends completely across the horizontal flow path of the water during the filtration mode of operation. The system is configured so that the buoyant media volume expands during a cleansing mode of operation.

Abstract: A unitized system for the processing of well water that is contaminated with volatile substances, such as organic substances, at a site where the contaminated water exists. This system has the primary components thereof mounted on a skid/frame that can be transported to the site. In the preferred form, the contaminated water is first processed in a spray tower where it is countercurrently contacted with air to remove the volatile contaminants. This air-treated water then is passed through an activated carbon bed for further purification before being used. While the treated water is not considered safe for human consumption, it can be used for most other uses. The system is controlled to normally operate only upon water demand by the system being supplied. Since activated carbon can cause the gradual growth of bacteria, the system is provided with a system for the periodic back flushing of the carbon bed, with the wash water being discarded in a separate holding tank or to a local sewer.

Abstract: A filter system for achieving continuous filtering by the provision of three filter chambers disposed about a common vertical axis, each containing a filter bed comprised of buoyant particles through which the fluid to be filtered is passed in an upward direction and wherein provision is made for rehabbing the beds of particulate material as they become filled with solids, preferably in succession to enable continuous operation.

Abstract: The invention contemplates a water-treatment system wherein inlet water is subjected to continuous circulation, or at least to a plurality of cycles of circulation, in a loop wherein air under pressure is injected into the water prior to passage through a magnetic-energy treatment device. The recirculation involves a tank which thus provides a volume of available pretreated water, against which to drawn in accordance with intermittent demand. Magnetic-field treatment of the aerated water creates particulates, from oxidizable impurities such as iron, and these particulates are separable by filtration; and as to those impurities as involve dissolved gases, such as radon or hydrogen sulfide, the gases are driven from solution and vented (along with excess air) external to the treated-water outlet of the system.

Abstract: Improvements in centrifugal pellet dryers including replacement parts for those areas of a centrifugal pellet dryer that are most subject to wear during normal use when drying pellets. The feed chute, base section and top section with pellet discharge chute are replaceable thereby avoiding the necessity of providing a completely new housing structure or a completely new pellet dryer when the dryer has become worn during normal use. The replaceable parts are substantially duplicative of the parts which they replace and are secured in place by conventional fastening and sealing arrangements.

Abstract: A single chamber filter module containing a buoyant bed of filter particles through which the fluid to be filtered is passed in an upward direction through the bed so that the solids become trapped within the bed. The filtrate is withdrawn from the upper end of the module. Periodically, the filter bed is rehabbed by dispersing the bed, washing the entrapped solids from the particles and discharging the solids from the lower end of the module.

Abstract: A filtration system and method for the removal of suspended solids from a contaminated liquid in which the contaminated liquid is pumped into the top of a vessel and allowed to flow through a bed of polyethylene particles which acts as a filtering medium. Periodically the flow of liquid through the polyethylene filter bed is stopped and a backwash cycle in which the contaminated liquid is pumped in a reverse flow direction through the filter bed is initiated. By thoroughly agitating the filter bed and polyethylene particles, contaminants are loosened and removed from the polyethylene particles and placed back into the liquid. The highly concentrated contaminated liquid is removed from the vessel for further processing. The filter bed is reset and the filtering cycle is again initiated.

Abstract: An apparatus for clearing the deposition formed on the bottom of a pond comprises a filter device for filtering the deposition, a suction water tube provided in the filter device with a plurality of suction pipes radially connected to one end thereof and capable of swiveling along with the suction water tube, and a plurality of pipings to connect the water suction tube to the filter device. There are suction inlets formed on the suction pipes for aspirating the pond water which is then fed into the filter device through the pipings and filtered therein. There is also provided a driving mechanism for actuating the water suction tube together with those suction pipes connected thereto to slowly swivel in the water of the pond. The water in the culturing pond will be cleaned from time to time so as to provide a good water quality for the culturing of the fishes in the pond.

Abstract: A reactivateable adsorption filter assembly comprises an adsorption filter element, a storage vessel in which is stored filtered fluid, a flow restrictor to restrict the flow of fluid between the adsorption filter element and the storage vessel and a purge valve on the inlet side of the adsorption filter element to selectively connect the filter assembly to a source of fluid at a low pressure, the arrangement being such that when the purge valve is opened to said source of fluid at low pressure filtered fluid containing adsorbate at a very low partial pressure flows back from the storage vessel through the adsorption filter element thereby reactivating said adsorption filter element.

Abstract: A filter for removal of suspended solids from fluids utilizes pressurized air for fluidizing filter media as the latter is exposed to backwashing water. The filter includes a casing having upright walls defining an annular chamber in horizontal cross-section, and a portion of the walls have openings that are pervious to liquid and substantially impermeable to the media particles. The flow of the backwash water is directed toward the upright, outer casing wall such that the backwash water flows at a direction at an angle relative to the upward flow of the pressurized air in the bed as the particles are fluidized, to facilitate removal of the accumulated solids without enabling escape of the media particles. Desirably, pressurized air is introduced into the chamber at vertically spaced locations to insure complete fluidization.

Abstract: A filter for use in conjunction with an intrachannel clarifier is provided comprising an enclosure, positionable within a channel and connectible to an intrachannel clarifier, and having a floor and sides; a filter compartment fixed within the enclosure, and having sides, either connected to or coincidental with the sides of the enclosure and segregating the interior of the filter compartment from the remainder of the enclosure; a porous medium support, fixedly connected to the sides of the enclosure and positioned within the filter compartment; a bottom, below the medium support and fixedly connected to the sides of the filter compartment; a filter medium, positioned within the filter compartment above the medium support; a conduit, connecting between the interior of the filter compartment beneath the medium support and the interior of the enclosure; a liquid dispersion mechanism, positioned within the filter compartment above the filter medium, for receiving liquid from outside the enclosure and dispersing

Abstract: An improved method of cleansing a filter bed is herein provided utilizing a backwash pump (12) having an inlet line (14) and an outlet line (16). The improved method and system includes two cycle operations. Initially, the filter bed is backwashed to remove contaminants from the filter bed with the backwash pump (12) drawing liquid from an effluent channel (26). A portion of the liquid passing on backwash pump outlet line (26) is passed through a bypass adjustment valve (34) for egress on an outlet line (38) for recirculation to the effluent channel (26). The second stage of the cleansing operation is through a purging cycle where the filter bed is purged subsequent to the backwashing operation for removal of further contaminants from the filter bed.

Abstract: Apparatus for continuous filtration of a fluid, for example water containing solids, comprising a plurality of filter cells partially filled with mobile filtering material, each cell having an inlet and an outlet, means being provided for continuously supplying fluid to the inlets, a drain element for filtered solids being connectible to a limited number of cell inlets without interrupting the fluid supply to the other cell inlets, the drain element lowering the fluid supply pressure prevailing at the limited number of cell inlets to a value lower than the filtrate pressure prevailing at the cell outlets so that these cells are backwashed with filtrate such that the mobile filtering material only partially filling the cells is swirled in the turbulent filtrate flow within the cells and is thoroughly cleaned from adhering solids.

Abstract: An apparatus is disclosed which is useful in simulating the countercurrent flow of several fluid streams through a bed of solid contact material such as a selective adsorbent. The apparatus comprises a plurality of multi-port valves and is used to direct the flow of different streams into and out of a fixed bed of material at points which are periodically changed. The invention arises in the arrangement of the valves, which minimizes the number of required valves and also minimizes the undesired admixture of different streams in the process lines connecting the contacting bed to the main fluid transfer lines. The valves are arranged in three tiers, with the first tier having sets of valves arranged in series flow and the second tier having sets of valves arranged in parallel . The third tier of valves directs flows between two adjacent fluid feed or withdrawal conduits entering the contacting bed.