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 device for the separation of particulated solids from a pressurized fluid, in particular from a viscous mass of a thermoplastic material, with a cleaning system for the filtration element based on the "return pressure" principle.The device comprises a body having a fluid inlet conduit, two filtration assemblies that are connected to two conduits flowing together into an outlet conduit, and a flow-dividing valve that in rest position connects the inlet conduit with the separation conduits through the filtration assemblies, while in the cleaning position for one of the filtration assemblies the inlet conduit is connected with the other filtration assembly, thus causing part of the fluid that has been separated by this filtration assembly to pass with counterpressure through the filtration unit that is in the cleaning stage and through a discharge outlet housed in a compartment of the valve.In a similar manner the cleaning of the other filtration assembly is performed.

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: A filter comprising a housing including an inlet coupled to a fluid inlet and an outlet coupled to a fluid outlet, and a filter assembly disposed inside the housing and arranged to intercept the flow of fluid from the fluid inlet to the fluid outlet, the filter assembly comprising a stack of filter screen elements, each filter screen element comprising a generally annular screen and spacer means associated with the screen and defining at least one inlet chamber adjacent each annular screen at an upstream side thereof for collection of contaminants and at least one outlet passage adjacent each annular screen at a downstream side thereof for permitting drainage of filtered fluid, the filter assembly defining a multiplicity of inlet contaminant collection chambers adjacent a multiplicity of annular screen.

Abstract: A filter comprising a housing including an inlet coupled to a fluid inlet and an outlet coupled to a fluid outlet, and a filter assembly disposed inside the housing and arranged to intercept the flow of fluid from the fluid inlet to the fluid outlet, the filter assembly comprising a stack of filter screen elements, each filter screen element comprising a generally annular screen and spacer means associated with the screen and defining at least one inlet chamber adjacent each annular screen at an upstream side thereof for collection of contaminants and at least one outlet passage adjacent each annular screen at a downstream side thereof for permitting drainage of filtered fluid, the filter assembly defining a multiplicity of inlet contaminant collection chambers adjacent a multiplicity of annular screens.

Abstract: A method and an apparatus for removing filterable particles from water are disclosed. One or more filter bags made from a filter material suitable for filtering off the particles to be separated are disposed in a body of water with the bottom of the bag situated below the water surface and its opening situated above the surface. The water flows through the wall of the filter bag to the surrounding body of water, while the particles remain within the bag. After a certain amount of particles has been collected in the filter bag, backwashing is carried out and the particles removed and conducted to a place remote from the body of water. The method and apparatus are particularly suitable for restoration of lakes, rivers, water courses and similar water bodies.

Abstract: A fluid filtering stop valve having a body with a cylindrical chamber having a circumferential sidewall with inlet, outlet and flush ports, and a cylindrical plug member rotatably disposed in the chamber. The plug member has spaced apart first and second circular plates with an off-center filtering screen extending therebetween. The plug member is rotatably between a filtering position in which the screen is located in the fluid flow between the inlet and outlet ports, a backflushing position in which the screen is located in the fluid flow between the inlet and flush ports, with the filtering side of the screen toward the flush port, and a closed position in which an arcuate plate washer loosely retained between the first and second plates is positioned to seal the flush and outlet ports. In the filtering position the washer seals only the flush port and in the flush position the washer seals only the outlet port. The screen uses outwardly diverging ribs to reduce lodging of material between the ribs.

Abstract: A filter device comprises a central tube, a housing enclosing the central tube and defining an internal chamber therewith, and a filter body within the internal chamber. The central tube includes a plug between the inlet and outlet which directs the fluid to flow from the inlet through the filter body and out through the outlet. The housing and filter body are mounted for sliding movement axially of the central tube from a normal filtering position wherein the housing inlet communicates with the upstream side of the filter body, to a back-flushing position wherein the inlet communicates with the downstream side of at least a portion of the filter body. The housing may also include a valve member moved therewith under differential pressure between the housing inlet and outlet to regulate the pressure at the outlet.

Abstract: A filter assembly includes at least one filter unit, a plurality of conduits extending transversely past the filter unit, a plurality of valves actuable to connect the filter unit to the conduits for alternate forward and reverse fluid flow through the filter unit, a plurality of actuators designed to actuate said valves on a one to one basis and a single drive motor linked to all the actuators of a given filter unit. The number of valves and actuators per filter unit correspond to the number of conduits to which the filter unit is to be attached.

Abstract: A backwashable filter comprises (a) an outer case, (b) a rotatable, permeable filter drum, (c) a fibrous filter element supported on the surface of the drum, (d) one or more stationary backwash arms, (e) a feed inlet leading to one side of the filter drum and (f) a filter outlet emerging from the other side of the drum. The backwash arms are in close contact with the filter element. The tendency of the feedstock to bypass the filter and enter the backwash arms is thereby reduced.

Abstract: A filter for hot melt adhesive is carried within a passageway in a manifold and is rotatable therein between a filtering position in which hot melt adhesive is directed to the inner core of the filter at one end thereof, and a backflushing position in which hot melt adhesive is directed onto the outside surface of the filter at the opposite end thereof. In the filtering position, the hot melt adhesive flows from the inner core outwardly through a filter screen into the main passageway for collection and discharge from one end of the manifold. In the backflushing position the adhesive flow is directed from the outside surface of the filter in the reverse direction through the filter screen to dislodge filtered impurities therefrom, and then the impurities are carried out a drain at the opposite end of the manifold.

Abstract: A filter device is disclosed, comprising two compartments within a housing. The first compartment includes a filter element, of the screen or the disc types, with communication to the filtered fluid outlet of the housing. A controllable valve communicates the first compartment with the inlet of the housing across the second compartment. A drain valve connects the first compartment with outside the housing. For flushing the filter element by reverse-flow, the first valve is closed and the flushing fluid drains through the drain valve. In a further embodiment two or more filter elements and associated compartments and valves are installed, in parallel, within the same housing, so that by stopping the filtering operation of one of the filter elements, it becomes flushed with the product, filtered fluid of the other element.

Abstract: A filter comprising a housing including an inlet coupled to a fluid inlet and an outlet coupled to a fluid outlet, and a filter assembly disposed inside the housing and arranged to intercept the flow of fluid from the fluid inlet to the fluid outlet, the filter assembly comprising a stack of filter screen elements, each filter screen element comprising a generally annular screen and spacer means associated with the screen and defining at least one inlet chamber adjacent each annular screen at an upstream side thereof for collection of contaminants and at least one outlet passage adjacent each annular screen at a downstream side thereof for permitting drainage of filtered fluid, the filter assembly defining a multiplicity of inlet contaminant collection chambers adjacent a multiplicity of annular screens.

Abstract: A water filtering system for connection to at least one water supply to be filtered including a filter tank containing cartridge-type filter media with the tank being especially configured to provide an evenly distributed water flow through the filter media for efficient water filtration. The system further includes a special plumbing system and controls therefore for establishing a two stage filter cleaning operation wherein water is impingingly directed onto the filter media for flushing of the filter media and the filter tank in the first stage of the filter cleaning operation and water is directed through the filter media in a backwash direction in the second stage of the filter cleaning operation.

Abstract: The present invention provides a rotary drum filter wherein one or preferably two rotary drum filters are submerged in a tank of liquid to be filtered. Each rotary drum filter is comprised of a generally cylindrical tank having a perforated outer wall plate over which is applied a cloth type filter media. A suction pipe is included inside the rotary drum filter so that filtered liquid can be drawn into the rotary drum filter through the pressure differential established by the suction pipe. Clean filtered liquid exits the suction pipe to the industrial apparatus with which the filter apparatus is used. A backwash vacuum box extending generally the length of the rotary drum filter media is in contact with a portion of the rotary drum filter media. A partial vacuum is established in the vacuum box such that filtered liquid can be drawn outwardly from the rotary drum filter such that solids accumulated on the filter media are drawn off from the filter media thereby cleaning that section of the filter media.

Abstract: A filtration system is provided for a dry well in the form of a buffer tank made of concrete to remove sediment and pollutants from water supplied from a header to an inlet pipe in the tank, so that the water exiting from an outlet pipe is free of particulate matter and pollutants. This is accomplished by providing a sediment pit and a baffle at the inlet side of the tank and then passing the water through a multiple stage set of filters having different aperture sizes. These filters remove particles and pollutants from the water as it passes through the buffer tank on its way to a dry well drain pipe attached to the outlet of the buffer tank.

Abstract: A filter unit includes:(a) structure providing a porous barrier between a first zone from which liquid to be filtered is supplied, and a second zone to which filtered liquid flows, via the barrier,(b) the barrier including a series of elements defining grooves, and filtering media between those elements and communicating with the grooves,(c) certain of the grooves presented for reception of liquid flow therein from the first zone so that liquid flows from the certain grooves through the media,(d) others of the grooves presented for reception of flow from the media and for subsequent flow via the other grooves to the second zone,(e) control means for providing backflushing only as required as an alternative to periodic backflushing.

Abstract: Continuous, noncentrifugal, unit gravity, sedimentation process and apparatus for carrying out the process, for separating blood into an erythrocyte-enriched plasma fraction and a leukocyte/platelet-enriched plasma fraction.

Abstract: A multi-element filter unit includes backwash apparatus and comprises a filter casing with provision for alternative, oppositely directed process liquid and backwash liquid flows therethrough. A plurality of filter tubes are close spaced within the filter casing. A flange engages the filter tubes and divides the filter casing into first and second chambers. Apparatus for sequentially backwashing the filter tubes during a backwash interval removes collected solids from between the filter tubes by flow of backwash liquid from one filter tube outward toward the exterior of adjacent filter tubes.

Abstract: Apparatus for mechanical purification of waste water has a stationary hollow shaft which is installed in a vessel for waste water and carries a variable number of hollow drum-shaped frames with pairs of filters adjacent to the openings in their sidewalls. Waste water is drawn into the interior of the frames by a pump which is connected to one end of the shaft whereby the impurities deposit at the outer sides of the filters. Such impurities are removed from time to time by suction heads which are adjacent to the outer sides of the filters and are connected to a single sludge pump by discrete conduits, one for each frame. The inner sides of the respective filters are then sprayed by clean water which promotes segregation of impurities and their entry into the suction heads. Indexible valving elements are provided to connect conduits for admission of clean water into selected frames with a single source of clean water and to connect selected conduits for removal of impurities with the sludge pump.

Abstract: A filter capable of being cleaned by reverse flushing, comprises a housing including a fluid inlet, a fluid outlet, a flushing outlet, and a filter body disposed within the housing. The housing includes blocking members disposed on opposite faces of the filter body and axially spaced from each other to define a reverse flushing passageway from the fluid inlet to the flushing outlet through the portion of the filter body between the axially-spaced blocking members. At least one of the blocking members is movable axially of the filter body to reversely-flush the complete length of the filter body.

Abstract: A drum filter is disclosed mounted vertically within a tank which receives the liquid to be filtered. The drum is provided with inside and outside filter media layers and intermediate axially extending passages receiving filtered liquid flow, which is collected in a central tube extending vertically upward and adapted to be connected to a suction pump.A backwash arrangement includes a backwash flow passage directing flow successively through each of the axial passages as the drum is incrementally rotated about its axis.Collection troughs are positioned extending axially along the inside and outside periphery of the drum member so as to receive the backwashing flow and contaminants, with a flushing flow carrying off the contaminants from the tank for secondary filtration.The rotary indexing drive consists of a cylinder actuated ratchet drive with a sprocket wheel in engagement with a chain track located about the interior diameter of the drum member at its upper end.

Abstract: A vertically arranged filter drum (6) is installed in the feed chamber (2) of the cylindrical housing (1) of the filter, this drum having a closed upper end and an open lower end. The filter drum (6) consists of an outer (13) and an inner (14) supporting basket exhibiting a screen (15) with passage openings for the liquid to be filtered, as well as of a filtering basket (16) disposed between the two supporting baskets (13, 14), the filtering basket being made of a filter material, for example perforated sheet metal. The filter drum (6) is rotationally driven by a shaft (10), supported in a post (8) on the filter housing (1), and by a motor (11) and is seated with its lower open end with running clearance in the discharge chamber (4) of the filter housing (1). The liquid to be purified enters the feed chamber (2) of the filter (1) via the inlet (3), and the purified liquid leaves the filter through the outlet (5) of the discharge chamber (4).

Abstract: A self-cleaning renewable fluid filter that flushes a permanent filter media while the used oil is pumped out by the engine oil pump through a drain in the housing. The fluid filter has an inlet and a drain, a center core with an outlet, a drain valve normally closing the drain, a permanent fluid filter media inbetween the inlet and outlet, a plug for closing the outlet, an actuator for opening the drain valve and an improved bypass valve which bypasses fluid and enables reversal of fluid flow through the filter media during draining for flushing the media. The preferred drain valve actuator is an electric solenoid coil inside of the filter and the improved bypass valve is an annular valve around the center core and inside of a cylinder formed in an inlet end cap of the filter media.

Abstract: A self-cleaning filter installed in a cylindrical conduit for a liquid to be cleaned, such as cooling water for an industrial power plant, comprises a sieve spanning the conduit and undulating between an upstream and a downstream transverse plane. The interior of the conduit is divided into two or more sectoral compartments which are bounded by corresponding sieve segments on the downstream side and are provided with respective peripheral outlets leading to a drain, these outlets being normally closed by associated shutoff valves. To clean any sieve segment bounding a particular compartment, the upstream entrance to that compartment is obstructed by a flap valve while the corresponding shutoff valve is opened to generate a reverse flow across that sieve segment.

Abstract: A polyjet valve has an inlet opening into an inlet chamber normally communicating through a movable polyjet sleeve in variable amounts and in one direction with an outlet chamber having an outlet. There is a block to close the outlet and a conduit to establish backflow from the outlet chamber through the polyjet sleeve in the reverse direction and then to waste.

Abstract: An inlet pipe having two branch pipes and an outlet pipe having two branch pipes, between the inlet and outlet pipes of each branch, there being a dump valve and a dump control valve, each outlet branch pipe containing in it a filter, the dump control valve sensing the pressure on each side of the filter and being operable, on pressure differential building up, to open the dump valve; by opening of either one of the dump valves, the water will flow through the inlet tube, the inlet branch tube of the outer dump valve and rearwardly through the filter element. The filter element will thereby be backwashed, and the particulate material which has been built up will be at least partly discharged through the dump valve to drain.

Abstract: The apparatus comprises an enclosure divided into two compartments (13 and 14) by a partition wall (15) which has a circular row of apertures (16). Filtering elements (26) of hollow tubular shape are fixed in one (13) of the compartments by an open end on each one of the apertures (16). A rotary tubular arm (20) is mounted in the other compartment (14) and has an end which sweeps along the circle of apertures and coincides with each one of the apertures in turn. The arm has a device (21) at the rotatable end of the arm (20) for closing an aperture (16) of the partition wall (15) and the orifice (51) of the end of the arm and a suction pump (P) for applying a sudden counter-current hydraulic shock through the wall of each filtering element (26) in turn is provided.

Abstract: A rotary filter for polymers comprises an inward flow filter drum mounted in a housing and consisting of inner and outer filter barrels 7 and 6 which retain between them a cylindrical filter element 8 of wire gauze or porous sintered metal. The outer barrel has regularly spaced large openings in its outer surface which communicate through the thickness of the barrel wall and via divergent passageways with even larger openings on the inner surface of the barrel. In contrast, the inner barrel has a plurality of much smaller through openings in registry with each of the large openings. The drum is rotated by a hydraulic ram via a pawl and pinion drive to bring successive openings in the outer barrel into communication with passages 22, 23, through which accumulated solids are flashed from the corresponding areas of the filter element by the resulting reverse flow of filtrate. The filter minimizes downstream pressure fluctuations and may be used upstream of an extruder.

Abstract: A circular filter having separated inlet and outlet compartments such that cheese whey or the like is pumped into the vessel, is forced across a filter screen, and the filtered whey is discharged downstream for further processing. This invention incorporates (1) two rotating showers to clean the filter and (2) an outlet valve which recycles filtered whey for additional filtering and cleaning.

Abstract: A device for selective channeling flow of either one or two fluids to at least one flowthrough element, particularly for the flushing out of a filter having at least one hollow cylindrical filter element in a housing which has two connection holes for the input and discharge of the fluid, and a hollow rotary valve connected with the flowthrough element and with a secondary discharge. A mouthpiece is urged by a spring into connection with the flowthrough element. The rotary valve and each of the flowthrough elements has its own housing part. The mouthpiece of the rotary slide valve can be selectively brought into connection with one of the element connections.

Abstract: A device for removing foreign particles from a source of fluid under pressure which is adaptable to be connected to a faucet or the like. It comprises one or more screens which are provided to collect the foreign particles which might include small stones, calcium deposits and the like, such that the particles cannot pass through the mesh of the screen. Such screens are mounted on a rotatable member having an exteriorly accessible handle whereby the rotatable member and screens thereon can be rotated at least ninety degrees and preferably one hundred eightly degrees so that the force of the fluid under pressure cleans off the screen and enables it to be used again to collect or intercept other additional foreign particles.

Abstract: Periodically operating pressure filter for the concentration of a solid matter suspension, comprising a filtering tank with an input conduit for introducing the suspension to be filtered under pressure, and a drain conduit for removal of the concentrated sludge, and a number of filtering elements suspended from the ceiling, through which the filtrate flows and which are internally in communication with a filtrate collecting tank located above and which thereby collect sludge on their outer surface. The sludge has been arranged to be periodically detached by making the pressure inside the filtering element higher than on its outside. The filtrate is under atmospheric pressure in the collecting tank.

Abstract: Apparatus for removing suspended solids from electroplating solutions and the like includes a housed cluster of slotted plastic tubes about which are fitted fabric filter sleeves and through which the solution is normally forced into the tubes continuously in the course of filtering. The process is interrupted relatively briefly when likely to be impaired by solids build-up, and flushing with water at a common utility-source pressure is then uniquely valved to take place in the reversed direction sequentially through the several sleeves by way of relatively slender sparger pipes each mated within a companion one of the slotted tubes and proportioned to spray a multiplicity of fine high-velocity streams through the slots and forcefully directly against the surrounding filter sleeving, to dislodge particulate material for drainage.

Abstract: A backwash system for a swimming pool including a pool discharge line and a return line and a filter, characterized by a forward pump in fluid communication between the pool discharge line and the filter and a reverse pump in the return line, and a strainer housing of unique construction in fluid communication between the forward pump and the pool discharge line. The strainer housing includes a strainer basket separating the strainer port from the pool discharge line and the strainer port communicating with the forward pump. A pressure-actuated valve operates within the strainer housing to open fluid communication between the pool discharge line and the strainer when the flow of liquid is in the forward direction and to close the strainer port to the pool discharge line when the flow of fluid is in the reverse direction.

Abstract: A water intake device comprising a substantially cylindrical rotatable screen adapted to be at least partially submerged in a body of water, means for rotating said screen, a water supply conduit communicating with the interior of said screen to receive water flowing through said screen, means for backwashing a section of said screen as said screen moves by said backwashing means so as to clear and/or remove objects or fish caught on the exterior surface of said screen and duct means associated with said backwashing means to provide or define a flow channel or path to guide and/or carry the objects or fish away from the influence or suction of the water entering said screen to said water supply conduit.

Abstract: Method and apparatus for regenerating a diatomaceous earth filter cake of a pressurized liquid filter system by liquidizing the diatomaceous earth filter cake formed on filter elements in the filter chamber of the system; by uniformly mixing with the liquidized diatomaceous earth the insoluble particles, or impurities, removed by the filter cake from liquid that has passed through the cake; and by reforming the fluid cake with the impurities uniformly distributed throughout the filter cake. The liquidizing of the filter cake and impurities and mixing of the diatomaceous earth and impurities result from oscillations induced in the liquid in the filter chamber by several cycles of rapid reversal of the flow of liquid through the filter chamber.

Abstract: A cleaning method of an etched disc filter and the system therefor, in which a plurality of discs having grooved surfaces are assembled or piled one on top of another. This filter is used for removing cruds and the like in a nuclear plant. For separating cruds and the like from small flow passages provided between each two of the discs thus assembled, reverse cleaning is applied, with the discs relieved from an assembled or piled condition for providing clearances among the discs.