Abstract: In a method for filtering a suspension through a stationary filter having a vertical filter element arranged in a pressure vessel and for re-conditioning the filter after filtering, the filtrate is discharged from the bottom of the filter element during the main part of the filtering. After filtering, unfiltered suspension is discharged in a known manner from the pressure vessel later to be returned to the suspension inlet. Thereafter, back-wash is performed with another medium other than filtrate, an outlet for material deposited on the filter element being opened for removal of said material together with the back-washing medium. Preferably, before back-wash, drying of the material deposited on the filter element takes place by means of a gas medium circulating within the filtering plant.

Abstract: A process and apparatus for the filtration of a creosote process stream laden with insoluble materials is provided. The apparatus comprises a filtration apparatus of a shell-and-tube configuration having filter material within for the separation of the xylene from the insolubles; the apparatus is comprised within a creosote filtration system which further includes a means for periodically backflushing the filtration system to reduce clogging of the filter material. The process and apparatus herein also finds use for filtration of other materials, including tars, pitches, and wastewaters.

Abstract: A filter for flowing polymer having a filter element progressively advanced between an on-stream position communicating between the upstream and downstream passages and a backflush position. In the latter position, filtered polymer is forced through a segment of the element in the direction opposite to on-stream flow. The filter is advanced in steps alternately with the energization of a pump for creating the backflush pressure. The steps are determined to cause each filter portion to remain in the backflush position for at least two consecutive steps.

Abstract: A solid and liquid separator with a liquid filter, having an inner cylinder and an outer cylinder combined together to rotate synchronously to let solids naturally separate from liquid, and a filter for the separated liquid to be further filtered and the separated solids to be collected together away.

Abstract: An apparatus for producing ester includes an esterification device, a neutralization device connected to the esterification device, a distillation device connected to the neutralization device, a container connected to the distillation device for storing ester distilled by the distillation device, a filter casing connected to the container, and a ceramic filter set in the filter casing for filtering the distilled ester in a cross flow manner.

Abstract: Filter apparatus for continuously filtering fluids containing large amounts of particles, including large amounts of ultrafine particles. The filter apparatus includes filter media and a backwash system which continuously removes deposited filtrate from an inlet side of the filter media. The filter apparatus also includes means for at least temporarily retaining filtered fluid in an outlet chamber of the apparatus at a location immediately proximate an outlet side of the filter media, such that backwashing of the filter means occurs continuously and instantaneously as filtered fluid passes through the filter means.

Abstract: A filter changing apparatus for use with an extruder for plasticized synthetic plastic material has a housing with one or more bores for reciprocable cylindrical carriers of tubular filters. Each carrier is movable between at least one first position in which a stream of plastic material can flow from an inlet of the housing, axially into one end of the filter, radially outwardly from the filter and into an outlet of the housing, and at least one second position in which the carrier seals the inlet from the outlet or permits expulsion of contaminants and plastic material from the filter in a direction toward the inlet or into a second outlet of the housing.

Abstract: In an atmospheric diffuser for the treatment of paper pulp (thickening, bleaching, and/or washing) the flow of backflushing liquid is controlled so as to maximize the effective treatment of the pulp. The pulp passes upwardly in a vessel. A number of annular screen assemblies are provided, with at least one screen associated with each screen assembly. The lower screen includes a barrier wall with a passage in the barrier wall adjacent the bottom end of the screen. Liquid which flows through the screen must flow to the passage in order to be withdrawn from the vessel, as the screen is slowly moved upwardly. When the screen is rapidly moved downwardly to cause backflushing, the backflushing liquid at the top end of the screen is liquid that recently passed through the screen at that point, so the pulp at that point--which is the cleanest along the length of the screen--has a minimal chance of being contaminated.

Abstract: The present invention relates to a method and an apparatus for washing pulp according to which method the pulp is supplied onto a movable liquid-pervious support surface to form a substantially continuous layer; and washing liquid is supplied to the pulp layer and passed in several successive washing phases through different areas of the layer in such a way that the washing liquid gradually flows in the opposite direction compared with the flow direction of the pulp layer. According to the invention the washing liquid is divided in two or more partial flows which pass alternately through different washing phases in such a way that the washing liquid which in one phase has passed through the pulp layer flows past at least the washing phase preceding it in the flow direction of the pulp layer. The apparatus of the invention preferably includes a rotating cylinder having a casing surface of which serves as the liquid-pervious support surface for the pulp.

Abstract: A back flush filter system for a cleaning apparatus which includes a hollow filter member with a flow diffusing member inserted therein to cause the flow through the filter to be diffused into a substantially circumferential uniform flow passage through the entire area of the screen in both the filtering mode and the back flow mode of operation and including an atmospheric air vent to permit air entrapped within liquid flow system to escape and thus maintain a substantially air free liquid flow system.

Abstract: Blood bag system for separating whole blood into upper, middle, and lower components which can then be isolated from each other in an automated manner. The system comprises a primary or main blood bag having first and second outlet ports. The first outlet port communicates via tubing with a first satellite bag. The second outlet port communicates via tubing with a second satellite bag at one end and at the other end communicates with a tubular member extending into and toward the bottom of the main bag. In use whole blood is drawn into the main bag through an inlet port and centrifuged to form an upper, less dense plasma portion, a lower, more dense red blood cell (RBC) portion and an intermediate portion of buffy coat (including platelets). Pressure is then applied to the bag with the first outlet open and the second outlet closed to express all of the upper plasma through the first outlet port after which the first outlet port is closed and the second outlet is opened.

Abstract: A liquid intake assembly includes a filter member having a shower ring for removing solids from the outside surface of the filter member. The shower ring has an annular portion surrounding the filter member and a plurality of nozzle members for directing pressurized fluid in streams adjacent to and generally parallel to the outside surface of the filter member. The streams generate currents in the suspension removing the solids from the outside surface of the filter member.

Abstract: A filtration apparatus for filtering water has a filter cloth which is supported on one side by support means against the pressure applied by water being filtered. During cleaning by reverse flow of water the cloth billows away from said support and cleaning means contact the billowed out filter cloth to clean it. To improve the cleaning effect, the cleaning means comprise a movable plate which is contacted by a region of said billowed out filter cloth during the reverse flow. The plate has at least one aperture at which said reverse flow occurs, and the aperture is moved relative to the filter cloth by movement of the plate.

Abstract: A backflushable filter including a housing having an inlet coupled to an upstream fluid inlet and an outlet coupled to a downstream fluid outlet, a filter assembly including a plurality of cylindrical filters, defining an upstream surface communicating with the inlet and a downstream surface communicating with an axial hollow volume therein, the axial hollow volume communicating with the outlet, a backflushing assembly comprising a backflushing nozzle disposed in each axial hollow volume for backflushing engagement with each of the cylindrical filters at its downstream surface, and a backflush drain communicating with the upstream surface.

Abstract: An underdrain lateral for a liquid purification system is described. The lateral has three chambers, a primary chamber, a compensating chamber, and gas chamber. Turbulence is minimized during cleansing of the purification media by isolating the gas from the liquid and the backwash liquid. This is accomplished by feeding gas into the gas chamber so that the chamber is occupied by gas only during cleansing. Orifices in the wall between the primary and compensating chambers and in the baffle between the compensating and gas chambers provide compensation for even distribution of liquid in the lateral. The design also enables the use of cut out in the gas chambers to equalize gas pressures and flow among the laterals and throughout the system bed and cut outs in the primary chambers to equalize liquid pressure and flow along the laterals and throughout the system bed.

Abstract: A method of changing operating modes in automatic water filtering apparatus comprising inside-skin tubular membrane modules for filtering water, the possible filtering modes being: dead-end filtering; cross-flow filtering; and cross-flow filtering with continuous purging; both cross-flow filtering modes including recirculation in a loop; wherein two types of triggering are provided for filter membrane backwashes, a first one of said types being related to time periods between two backwashes, which time periods are predetermined for each mode of filtering, and a second one of said types being related to reference values of an operating parameter of the automatic apparatus, which values are predetermined for each mode of filtering; with the mode of filtering being changed after a backwash has been triggered in response to one of the reference values, with changes taking place in the following order: dead-end filtering, cross-flow filtering, cross-flow filtering with continuous purging, or vice versa.

Abstract: This invention relates to filtering or straining of fluids where the suspended solids removed by filtration must eventually be discharged from the filter as a "dry cake" discharge. The apparatus provides for the use of a central flow tube positioned within a filter element which is connected to a filter element drain pipe through a valve, which in case of multiple filter elements within a filtration vessel, controls draining of all elements. To assist in detecting a defective or malfunctioning filter element, a sample conduit with a sample valve is provided independently for each filter element.

Abstract: A reversible-flow filter assembly to be installed into a flow conduit, has a filter housing with a housing inner wall and an outlet socket projecting coaxially thereto centrally into the interior of the filter housing. Further, the filter housing has a guiding member arranged coaxially thereto but spaced therefrom in the filter housing. The interspace between outlet socket and guiding member is bridged by a filter forming an annulus. The inlet is connected to the annulus. A suction device engages the outer surface of the filter with a limited suction opening. The suction device forms a housing fixed annulus, which is connected to the suction opening engaging the filter and can be connected to the drain through an outlet valve. The filter is located in a filter support which is movably guided on the outlet socket by a first guiding element and on the guiding member and in the suction device by a second guiding element. A control pressure chamber below the second guiding element is connected to the annulus.

Abstract: A cage-culture turbidostat as described for growing organisms at a constant population density which avoids the problem of filters clogging and nutrient dilution and facilitates the analysis of the growth and development of the organisms. The cage-culture turbidostat minimizes reintroduction of spent nutrient medium through the filters during backwashing.

Abstract: Method and equipment for filtration of a suspension so that the suspension to be filtered is fed from a feed part (4) onto the filter face of a filter member (5), which moves relative the feed part. The pulp layer is formed on the outer face of the filter member and the filtrate flows into the interior of the filter member, and the pulp layer is removed from the filter member at the removing point. After the pulp removing point (17), before the feed point (4), one or several cleaning points (12) are provided wherein liquid is made to flow through the filter member (5) from the inner face of the filter member to the outer face. The flow rate of the liquid that flows through the cleaning point or points is adjusted higher than the rate of any liquid flow that may flow through the rest of the filter member from the inside-face side to the outside-face side.

Abstract: A recirculating toilet water system includes: a toilet, a main water tank for storing water and receiving waste matters from the toilet, a filtered water supply means for supplying filtered water as filtered through a screen from the main water tank for flushing the toilet and an air supply means for delivering compressed air for boosting the filtered water for flushing the toilet, wherein the water supply means includes a feed water valve which is normally opened to fludically communicate a flushing water tank with the main water tank to lead water into the flushing water tank and is operatively closed when boosting the water for flushing the toilet by the compressed air, and is further provided with a purging perforation therethrough to eject a partial stream for purging the screen for preventing the clogging of particulate matters on the screen when boosting the water.

Abstract: A method of backwashing bundles of inside-skin tubular filter membranes in modules, in which:a circuit is provided so that dead-end mode filtering takes place with the tubular membranes being fed from one end while cross-flow mode filtering takes place with the tubular membranes being fed from the other end, thereby ensuring in both cases that the major portion of the matter stopped by the membranes collects in the same relatively small zone in the bundles of membranes contained in the modules;water is drawn off from the periphery of the modules; andbackwashing is performed in two stages: a first stage in which all of the backwashing water is used for cleaning said relatively small zone and in which the recirculation loop that enables cross-flow filtering to be performed is closed; and a second stage in which the backwashing water is caused to pass through all of the membranes and all the recirculation loop.Apparatus for implementing the method is also described and is shown in FIG.

Abstract: A closed, cross-flow fluid filter assembly having a pressurized input line for polluted fluids entering into a closed header box. The closed header box fits within a filter tank and is provided with apertures and spacer assemblies on the bottom wall thereof communicating with the filter tank, the apertures providing the pressurized fluid thereto. Filter leaf assemblies are arranged in parallel within the filter tank and are maintained at their top edges in spaced relation by the spacer assemblies. The filter leaf assemblies are composed of abutting offset grids, contained within a fluid tight frame which is covered on each side by a filter media. The filter leafs are drained of filtrate through a medial tube connected to a central manifold which is connected to a vacuum source. Flow-through backwash stop-grids are arranged in the filter tank to prevent excessive bulging of the filter membranes during backwash for cleaning of the filter media.

Abstract: An apparatus for preparing a machining liquid of an electroerosion machine comprises a filter to which is supplied a concentrate flow and from which a permeate flow is drained off. The filter is constructed as a membrane filter, the clogging of which is prevented in that the concentrate flow direction is periodically reversed.

Abstract: An apparatus for dewatering a pulp is described, comprising a vessel having a pulp chamber for pulp to be dewatered; a pulp inlet to the vessle; pulp outlet from the vessel; a filtrate chamber with an outlet for filtrate expelled from the pulp; a stationary cylindrical screen mounted within the vessel and defining said plup chamber and filtrate chamber on opposite sides thereof; and mechanical cleaning means supported by a shaft and disposed in the pulp chamber close to the screen face of the screen for removing a mat of pulp therefrom. The apparatus further comprises a backflushing means mounted outside the vessel and including a cylinder with first and second end portions and a piston mounted within the cylinder for reciprocal movement therein. The first end portion communicates with the interior of the apparatus, and the second end portion communicates with the filtrate chamber.

Abstract: A fluid filter including a housing defining a fluid inlet and a fluid outlet and a filter element defining an upstream surface communicating with the fluid inlet and a downstream surface communicating with the fluid outlet, the filter element including at least one group of disk-like elements including at least one element of relatively fine porous material, having disposed on both sides thereof disk like elements of a relatively coarse porous material, each of the at least one groups having disposed on both sides thereof a grooved spacer element.

Abstract: A filter element comprising at least one coiled filter strip defining first and second butt ends, one of the butt ends being arranged to define an upstream surface during normal filtering operation, receiving fluid to be filtered, and the other of the butt ends being arranged to define a downstream surface during normal filtering operation, through which filtered fluid leaves the coiled strip.

Abstract: A filtering system for liquids with suspended particles is disclosed. The system consists of a receptacle for the liquid with suspended particles, a receptacle for the filtered liquid, a decanting receptacle for residual liquid, a filter, and a valve unit. The valve unit interconnects the receptacles through the filter in order for the filter to perform a filtering phase of filtering the liquid with suspended particles from the receptacle for liquid with suspended particles to the receptacle for filtered liquid; a filter-washing phase against the filter-flow from the receptacle for liquid with suspended particles to the decanting receptacle; and a rinsing phase from the receptacle for liquid with suspended particles to the decanting receptacle.

Abstract: A liquid filtering and backwashing apparatus is disclosed comprising a pressurized filter tank having a first outlet valve and a filter cell disposed within the filter tank. The filter cell includes a conduit and an outer member with the outer member spaced apart relative to the conduit with a filtering medium positioned between the conduit and the outer member. A plurality of openings in the outer member enable fluid communication between the liquid to be filtered in the filter tank and the filtering medium. The conduit is provided with a plurality of slits to enable the pressure in the tank to force fluid communication between the filtering medium and interior of the conduit while retaining the filtering medium external the conduit. Means are provided to vary the size of the slits to adjust for differing pressures or filtering requirements. A backwash holding tank in fluid communication with the conduit collects the filtered liquid.

Abstract: A back flushable filter which has a number of separable sections (2) which can be separately accessed and there can be provided a flow pattern so that one of the sections is being back flushed while the other sections are providing normal filtering. A valve configuration (11) providing for such access can be inched around to select each section in term. The filter preferably comprises a stack of separable segments which provide for inclined gaps between adjacent parts of each adjoining stack element with the convergents and gap size selected to encourage compaction of particles within the converging part of each gap but further selected such that on back flushing such compacted particles can be readily disgorged for total cleansing.

Abstract: The present invention comprises a closed-loop filter system for continuously removing a metal hydroxide precipitate from an alkali metal hydroxide solution. The filter system comprises a filter having a filter surface and a plurality of small diameter openings in said surface. The alkali metal hydroxide solution is impacted onto said filter surface, metal hydroxide precipitate agglomerating on said surface. The filter surface openings have an average diameter effective for said agglomerating. Means are provided to remove the agglomerated precipitate from said filter surface, and to separate the agglomerated precipitate from the alkali metal hydroxide solution, the agglomerated precipitate having a particle weight to surface area ratio effective for said separation.

Abstract: The present invention relates to a method and apparatus for the continuous discharge of water from suspension, especially from fibrous pulp, whereby pulp is caused to thicken without having the water to be removed through a thick uncontrollably gathered fiber mat.In accordance with the invention the suspension to be thickened is fed into a filtering chamber, the suspension is formed as a layer that is continuously being mixed for equalizing the consistency differences, the liquid is continuously removed from the suspension and the thickness of the fiber mat being formed on the filter surface is controlled by subjecting said mat to shear stresses.The above described method is realized by an apparatus, in which at least one of the co-operating surfaces, the filtering surface (8) and its counter surface (10), is provided with means (12) for non-mechanically limiting the thickness of a fiber mat on the filtering surface, whereby a uncontrolled formation of a fiber mat on the filtering surface (8) is prevented.

Abstract: In rotating disc filters used for example in the pulp and paper industry, one or more spray elements are positioned between adjacent discs to rotate about an axis parallel to the disc axis. This arrangement achieves greater washing coverage of the discs than prior systems.

Abstract: A fluid flow fill valve (10) has an elongated strainer member (40) with a plurality of axially extending flanges (44) each having alternating notches (48) and comb-like elements (46) which abut a complementarily tapered supply conduit wall (25) to provide an elongated strainer member along the conduit. The upstream end of the strainer member (40) has a nub (64) which is placed within an aperture (74) of flexible fluid flow restrictor member (66) to provide for a restrictive annular inlet to the strainer member (40). Strainer member (40) can be easily flushed by depressing and axially moving the strainer member downwardly such that a clearance (84) is formed between the comb-like element (46) and the tapered wall (25) of conduit (24).

Abstract: A dishwashing machine includes a recirculating pump having a casing, an inlet communicating with a sump of a washing tub, an outlet communicating with a spray arm located above the sump, and an impeller rotatable within the casing in a recirculating direction during a washing phase of operation of the machine and rotatable in a direction opposite to the recirculating direction during a drain phase of operation of the machine. A recirculating filter is positioned between the spray arm and the sump. To ensure that all water collected in the sump adjacent the inlet of the recirculating pump is discharged during the drain phase of operation of the machine, a conduit has a first end connected to the interior of the casing of the recirculating pump and a second end positioned adjacent the recirculating filter.

Abstract: A filtration apparatus characterized by efficiency of the precoating step and maintenance of filtration performance over a long period of time after precoating has been completed. The filter promotes parallel flow of porous precoat material along a porous septum, thereby achieving efficient stacking of this material against the septum. A dual-speed pumping system transmits the precoat material to the septum at high velocity, thereby further encouraging efficient stacking, but pumps the fluid to be filtered at a lower velocity to minimize energy consumption.

Abstract: Backflushing with internally mounted pistons and cylinders is provided in a pulp treating vertical vessel such as a paper pulp thickener, diffuser, or displacement bleacher. First and second sets of screens are mounted on a supporting arm/conduit within the vertical vessel, the first screens mounted directly to the arms and the second screens mounted on top of the first screens. A first cylinder is connected at one open end to the conduit and at the other open end is exposed to the pulp within the vessel. A second cylinder is mounted so that it is concentric with the first cylinder and both ends are in operative communication with the liquid conduit. A piston is mounted within each cylinder by a common vertically extending piston rod which connects them. The pistons and cylinders have different effective diameters.

Abstract: An apparatus for filtering a liquid, includes supplying a starting liquid from a container to a passage of a pipe-like filter set in a filter casing, passing the starting liquid through the passage of the filter thereby to produce the filtrate, sending back the unfiltered liquid to the container, and back washing the filter by means of a hydraulic pressure device having a piston movable in a cylinder in such a manner that the filtrate is moved by the piston of the hydraulic device.

Abstract: A method for application in conjunction primarily with so-called rotating filters of the kind which include a substantially cylindrical filter tube (1) which is provided with a permeable wall and which is sealingly journalled at preferably two axially spaced locations, preferably at the ends of the tube, and which is arranged for rotation about its longitudinal axis in a filter jacket (2), wherewith material to be filtered, the so-called feed, is supplied to a space or chamber (11) located between the filter jacket and the filter tube, and the filtered substance, the filtrate, being tapped-off from the interior of the filter tube.The method is particularly characterized by sealing and journalling the filter tube (1) in a manner adapted to substantial changes in temperature in the filter tube and that facilities are provided for sterilizing the filter.

Abstract: A process is disclosed for recovering a cellulose ether from a cellulose ether suspension in which the cellulose ether is recovered as a filter cake from a pressure filtration, particularly using a rotary pressure filter. Clogging of the separation or filtration device is avoided, providing for a long useful life. A multi-layer wire mesh filter medium is employed, formed of mesh layers of different wire thicknesses and/or mesh size. After removal of the filter cake, the filter medium is cleaned with steam, compressed air or pressurized water.

Abstract: A purgeable plastic injection filter nozzle for trapping and eliminating contaminants from molten plastic material in a plastic injection molding apparatus. A nozzle body has an internal main channel therethrough for flow of the molten plastic. A purging hole intersects the main channel and exits the side of the nozzle body. A rotatable housing is mounted in the nozzle body at the intersection of the main channel and the purging hole. A trap is mounted in the rotatable housing for trapping contaminants in the plastic. The housing is rotatable between a first position wherein the trap is in the flow of the molten plastic, and a second position wherein the trap may be purged of contaminants through the purging hole.

Abstract: An apparatus and process of filtering fluids, such as white water is provided for use in the place of an existing save-all device or downstream of an existing save-all device at a paper-making mill. The white water having contaminants in a suspended state is introduced into the filtration vessel and is withdrawn from the interior of the filter element positioned within the filtration vessel. To clean the filter element from the cake which has built up on the exterior surface of the filter element, a backflushing shock is applied to the interior of the filter element, forcing all cake settled on the exterior to be dislodged, thereby cleaning the filter element. The backflushing shock is delivered from a backflushing reservoir wherein the backflushing fluid is contained under pressure at a level at least slightly above the level of a pressure differential which has built up across the filter element. The shock is applied for a period of 1-2 seconds, during which time the backflush reservoir is emptied.

Abstract: A filter in which liquid flows through a plurality of filter elements wherein each filter element has a pair of valves for closing off the ends of the filter elements in turn for filtering and backwashing. The valves are mounted on a common stem operated by an actuator. With the actuator on, the backwashing or cleaning valve is closed and the remaining or inlet valve is open. With the actuator off, the inlet valve closes and the backwashing valve is opened.

Abstract: A fluid filter comprising a housing defining a fluid inlet and a fluid outlet, a filter element defining an upstream surface communicating with the fluid inlet and a downstream cylindrical surface communicating with the fluid outlet, the filter element comprising a stack of filter disks defining a hollow volume interiorly thereof and a longitudinal axis, and backflushing means for removing filtered out sediment from the filter element comprising an axially displaceable backflushing nozzle assembly disposed within the hollow volume comprising a rotating head coupled to the fluid inlet and having fluid outlet means, arranged to provide a generally radially directed pressurized jet and rotational motion of the rotating head.

Abstract: A conventional filtering system of a swimming pool is modified by the provision of an adaptor which is shaped to be inserted into the discharge opening of the pool skimmer so as to prevent extraction of water from the pool into the filter system. The plug member is shaped with a lower cylindrical plug portion two inches in diameter so as to insert into the discharge opening. A channel runs along the length of the plug member and opens at its upper end into a female screw threaded coupling for receiving the conventional male screw threaded end of a garden hose through which fresh water is supplied for the backwashing of the filter.

Abstract: In the cleaning and removal of solids from microporous hollow fibre filters by a series of chemical cleaning cycles, the optimum time and pattern of the cleaning cycles is calculated from the rate of diminution in filtrate flow rate and the time and filtrate lost in each cycle.

Abstract: The present invention relates to a method and an apparatus for washing pulp according to which method the pulp is supplied onto a movable liquid-pervious support surface (2) to form a substantially continuous layer (7); and washing liquid is supplied to the pulp layer and passed in several successive washing phases through different areas of the layer in such a way that the washing liquid gradually flows in the opposite direction compared with the flow direction of the pulp layer. According to the invention the washing liquid is divided in two or more partial flows which pass alternately through different washing phases in such a way that the washing liquid which in one phase has passed through the pulp layer flows past at least the washing phase preceding it in the flow direction of the pulp layer. The apparatus of the invention preferably comprises a rotating cylinder (1) the casting surface (2) of which serves as the liquid-pervious support surface for the pulp.

Abstract: A backflushable filter including a housing having an inlet coupled to an upstream fluid inlet and an outlet coupled to a downstream fluid outlet, a filter assembly including a plurality of cylindrical filters, defining an upstream surface communication with the inlet and a downstream surface communication with an axial hollow volume therein, the axial hollow volume communicating with the outlet, a backflushing assembly comprising a backflushing nozzle disposed in each axial hollow volume for backflushing engagement with each of the cylindrical filters at its downstream surface, and a backflush drain communicating with the upstream surface.

Abstract: In the cleansing especially of cooling water for a heat exchanger the installation of rotationally symmetric filter bodies in the cooling water feeder pipe and suction of sediments across a suction nozzle rotating on the windward side. Difficulties result therein in the production of a required back-flow through the filter and the avoidance of lateral airfluxes in front of the filter surface, as a certain gap is necessary between filter and suction nozzle for holding the sediments.

Abstract: A filter apparatus for separating solids from a liquid in a slurry, is cleaned by a jet and a sludge removal device. The filter is generally flat and has an inflow side on which the solids are deposited and an outflow side supported by a grid. The grid subdivides the outflow side into a plurality of separate injection chambers and defines a plurality of separate small regions of the filter material. The jet directs a stream of liquid through one of the injection chambers and against one of the small regions of the filter defined by the injection chamber. A cover plate is provided on the jet for engaging the grid to close one injection chamber opposite the filter material. The sludge removal device is located on the inflow side of the filter and is aligned with the jet to receive solids dislodged from the filter. The jet and sludge removal device more simultaneously and in alignment with each other to close selectively and to direct a stream of liquid through each of the injection chambers.