Abstract: An apparatus and method are provided that enable the control of a screening operation based on a calculated screen blockage percentage and the velocity throughput of the screen. The apparatus includes an upstream level detector, a downstream level detector and a flow determining device which determines the volumetric flow through the screen. The apparatus may further include a blockage determination unit which determines the percent screen blockage based on the flow level upstream of the screen, the flow level downstream of the screen and the volumetric flow.

Abstract: A screening device for wastewater includes a perforate screening member through which wastewater in an associated channel flows from a bottom side thereof to a top side thereof. An overfall wall is positioned in the wastewater channel. A clearing member is shiftable relative to the screening member for cleaning screenings therefrom, and is positioned upstream of the overfall wall. A waterwheel is positioned in the wastewater channel at a location downstream of the overfall wall, and is operably connected with the clearing member for mechanically shifting the same to remove the screenings from the screening member without using external power.

Abstract: A variety of improved hydroclone based fluid filtering systems are described. The hydroclones generally include a tank having an internal chamber and a filter (preferably a surface filter) that is positioned within the internal chamber. The filter defines a filtered fluid chamber within the internal chamber of the tank. The hydroclone may be operated such that a vortex of flowing fluid is formed between the chamber wall and the filter with the filter being located in the center of the vortex. With this arrangement, the filter acts as a cross-flow filter. In one aspect of the invention, the filter is a stepped filter. In another aspect of the invention, the filter is an surface filter, as for example, an electroformed metal surface filter. In some preferred embodiments, the openings in the filter are arranged as slots that extend substantially vertically so that they are oriented substantially perpendicular to the flow path of fluid flowing in the adjacent portion of the vortex.

Abstract: The present invention provides a flow-control support for a distributor plate in a composite pressure vessel. The distributor plate includes a thermoplastic polymeric disk having a top side, a bottom side, a perimeter edge and a central opening and a plurality of fluid flow passages through the disk. The flow-control support is disposed between the bottom side of the disk and an inner side of an end of a thermoplastic liner assembly. The flow-control support includes a spirally fluted upper surface that is adapted to direct fluid flowing from a supply pipe disposed in the central opening of a distributor plate that is supported by the flow control support such that the fluid swirls in a space between the bottom side of the distributor plate and an inner side of an end portion of a water treatment vessel. The swirling water insures that fluid is distributed to substantially all of the fluid flow passages through the disk during backwashing operations.

Abstract: An apparatus for filtering suspended solids from a liquid having a group of filters mounted inside a filter chamber. The filters divide the chamber into dirty liquid chambers and clean liquid chambers. A wash assembly is disposed within the chamber having vacuum/pump heads in contact with the filters rotates within the chamber. The vacuum/pump heads are connected to a pump and vacuum source located either within or without the apparatus. The vacuum/pump heads either vacuum material up or spray material therefrom in order to clean the filters. As the wash assembly rotates, the vacuum heads are able to contact and clean the entire surface of the filters. The filters are reasonably mounted in the chamber such that they may be removed from the chamber for servicing/replacement without the need to drain the chamber or enter the chamber.

Abstract: Method and arrangement for continuous filtering of particles out of a contaminated liquid by means of a number of separate filtering units (14) in order continuously to feed purified liquid to a consumer. Each filtering unit (14) comprises a rotatable, perforated drum (16) with a particle-catching filter means (18) on the outer surface of the drum. A first predetermined degree of coating with particles is created on the filter means of the drums, and purified liquid inside all the drums of the filtering units (14) except at least one, which is kept inactive in a standby state by shutting off the associated pump (26), is then fed to a consumer. The feed of purified liquid from a drum to the consumer is interrupted when a second predetermined, higher degree of coating with particles has been reached on the filter means on an individual drum, at least one filtering unit kept in standby state being activated as replacement for the filtering unit(s) from which the feed of purified liquid has been interrupted.

Abstract: A sludge removal apparatus includes a sludge removal head (10) with a sludge suction duct and an water supply duct with open end portions alongside each other, and a filter (32) adjacent to the open ends of the suction duct (36) and the water supply duct (38) so that the sludge is extracted through the filter (32). A drive mechanism moves the filter so that regions of the filter pass successively over the open ends of the suction duct, where it may become partially blinded with sludge, and then over the water supply duct where it is backwashed.

Abstract: A self-cleaning screen that automatically cleans both the inside and outside surfaces of the cylindrical screen using only the rotation of the cylindrical screen itself. This self-cleaning ability is accomplished by using a fixed brush on the exterior surface of the screen, and a freely rotating brush on the interior surface of the screen, where the freely rotating brush is driven by the movement of the screen itself.

Abstract: The present invention relates to the thickening of pulp suspensions. A low consistency pulp suspension is fed to a pre-thickener (10) through an inlet conduit (18). A layer of thickened pulp, formed on a filter surface (22), is pushed along the filter surface by a cleaning member to the discharge end of the pre-thickener and is discharged through the outlet (20). The cleaning member comprises a rotating shaft (30), on which shaft at least one screw thread (32) is fixed so as to leave a free space between the shaft and the screw thread. Essentially non-thickened pulp is allowed to flow through the apparatus via this space.

Abstract: A self-cleaning mechanical filter comprises a mechanism for simultaneously cleaning the internal surface and the external surface of a filter element. The filter is provided with structure for performing suction scanning of solid materials accumulated on the internal surface of the filter element, and structure which can be operated in synchronization with the suction scanning structure for backwashing the external surface of the filter element during a self-cleaning process.

Abstract: The present invention provides a system and method for providing a self-cleaning water circulation system which may be utilized for a fish pond, fountain, or the like. Means for automatically cleaning the pump intake to avoid pump failure due to leaves and debris is provided. The circulation system also comprises a self-cleaning filter for cleaning the circulated water whereby maintenance requirements are substantially reduced.

Abstract: Apparatus and methods include an improved filter (203) and cleaning process.

Abstract: A spin filter apparatus for cleaning an influent stream is provided and includes a housing having at least one inlet port for receiving the influent stream, at least one waste port for discharging waste and at least one output port for discharging a processed clean effluent stream. The apparatus also includes a discharge conduit coupled to the at least one outlet port for discharging the processed clean effluent stream; and a spin filter assembly disposed within the housing and including a filter screen set formed of at least two screen filters that are rotatable about the discharge conduit and freely movable in a vertical direction along the discharge conduit.

Abstract: A drilling water filter (1) with a self-cleaning system including a filter container (2), a cover (3) and a filter element (6) that can be inserted in the flow arm between an inlet (4) and an outlet (5) for separation of solid material from the fluid. The cover (3) has a displaceable carrying handle (7) for transporting the drilling water filter. The carrying handle (7) is connected with at least one self-cleaning means, in a controlled manner.

Abstract: A self-cleaning, back-washable filter apparatus and method for use with a pumping apparatus which is lowered into a well casing. The filter apparatus includes a filter basket having a manifold with several tubes extending therefrom. A filter sock encases at least a portion of the filter basket to block sand or other solid particles from entry into the pump intake. Pressurized gas or fluid is directed to the manifold and then through perforations or jets distributed along the length of the tubes. Bursts of the pressurized gas are directed from the perforations or jets to the interior of the filter apparatus and then sprayed from the perforations or jets in an outwardly direction against interior surfaces of the filter sock. Air or fluid bursts from the perforations impinge upon the interior surfaces of the filter sock and dislodge or expel entrapped particulate material.

Abstract: A liquid filtering apparatus for mounting in a housing defining an inlet and a drain. The liquid filtering apparatus is positioned in use to filter liquid flowing from the inlet (23) to the drain. The apparatus comprises a permeable screen (19) rotatable about a substantially horizontal axis and forming a barrier between the inlet and the drain. A rotatable wheel is disposed within the screen and coupled to the screen so that rotation of the wheel causes rotation of the screen. The wheel is defined by vanes (5-12) extending towards the screen so as to divide a space around which the screen is arranged into sections which are substantially isolated from each other except via the drain. A stationary baffle (13) is arranged adjacent a portion of the screen to prevent liquid from flowing into the wheel through that portion of the screen. The baffle is positioned such that water flows more readily into sections of the wheel on one side of a vertical plane through the rotation axis than the other sections.

Abstract: The present invention relates to the thickening of pulp suspensions. A low consistency pulp suspension is fed to a pre-thickener (10) through an inlet conduit (18). A layer of thickened pulp, formed on a filter surface (22), is pushed along the filter surface by a cleaning member to the discharge end of the pre-thickener and is discharged through the outlet (20). The cleaning member comprises a rotating shaft (30) on which shaft at least one screw thread (32) is fixed so as to leave a free space between the shaft and the screw thread. Essentially non-thickened pulp is allowed to flow through the apparatus via this space.

Abstract: An apparatus for filtering suspended solids from a liquid having a group of filters mounted inside a filter chamber. The filters divide the chamber into dirty liquid chambers and clean liquid chambers. A wash assembly is disposed within the chamber having vacuum/pump heads in contact with the filters rotates within the chamber. The vacuum/pump heads are connected to a pump and vacuum source located either within or without the apparatus. The vacuum/pump heads either vacuum material up or spray material therefrom in order to clean the filters. As the wash assembly rotates, the vacuum heads are able to contact and clean the entire surface of the filters.

Abstract: A self cleaning filter includes a body (15), inlet (1), outlet (14), flush inlet (12) and waste outlet (2). Elements (7) provide filtration while compressed but are cleaned decompressed. Feed from inlet port (3), impacts and swirls from an impeller (5) on moveable plunger (6) for preliminary centrifugal separation. During filtration plunger (6) is positioned to open the inlet port (3), the filtrate port (11) and compress filtration elements (7). The swirling feed permeates the filtration elements (7) and passes filtrate port (11), filtrate valve (21), filtrate plenum (16), and exits the filtrate outlet (14). Plunger (6) is moved and cleaning is provided by supplication of pressurized cleaning media to the back flush receiver plenum (13) via the back flush media inlet (12). This pressure motivates plunger(6) to close inlet port (3), filtrate port (14) and decompress filtration elements (7).

Abstract: A back flushable filter comprising a body (15), a raw feed inlet (1), a filtrate product outlet (14), a back flush media inlet (12) and a back flush waste outlet (2). A a filtration element (7) is used which provides filtration when in a compressed, sealed state and can be back flushed clean when released in a loosened state. During filtration, raw feed water passes through an inlet port (3), impacts upon and exits radially with swirl from a centrifugal impact impeller (5) mounted in conjunction with the upstream side of the filter element sealing plunger (6). The swirling raw feed water passes adjacent to and then into and through the filtration element (7). The filtrate then exits the internal filtrate sector of the filtration element (7) via the filtrate port (11) past the open filtrate valve (21), into the filtrate plenum (16) and is discharged via the filtrate outlet (14).

Abstract: A self-cleaning, back-washable filter apparatus and method for use with a pumping apparatus which is lowered into a well casing. The filter apparatus includes a filter basket having a manifold with several tubes extending therefrom. A filter sock encases at least a portion of the filter basket to block sand or other solid particles from entry into the pump intake. Pressurized gas or fluid is directed to the manifold and then through perforations or jets distributed along the length of the tubes. Bursts of the pressurized gas are directed from the perforations or jets to the interior of the filter apparatus and then sprayed from the perforations or jets in an outwardly direction against interior surfaces of the filter sock. Air or fluid bursts from the perforations impinge upon the interior surfaces of the filter sock and dislodge or expel entrapped particulate material.

Abstract: A self-cleaning, back-washable filter apparatus and method for use with a pumping apparatus which is lowered into a well casing. The filter apparatus includes a filter basket having a manifold with several tubes extending therefrom. A filter sock encases at least a portion of the filter basket to block sand or other solid particles from entry into the pump intake. Pressurized gas or fluid is directed to the manifold and then through perforations or jets distributed along the length of the tubes. Bursts of the pressurized gas are directed from the perforations or jets to the interior of the filter apparatus and then sprayed from the perforations or jets in an outwardly direction against interior surfaces of the filter sock. Air or fluid bursts from the perforations impinge upon the interior surfaces of the filter sock and dislodge or expel entrapped particulate material.

Abstract: Reverse osmosis filtration is conducted using a rotatable inner body having an axis of rotation and a reverse osmosis filter member disposed on the inner body. An outer body is disposed about the inner body and spaced therefrom to provide an annulus between an annular outer surface of the filter member and an annular inner surface of the outer body to receive a liquid to be filtered. A source of the liquid under pressure is communicated to an inlet to the annulus. The inner body is rotated at a rotational speed effective to generate Taylor or other vortices in the liquid in the annulus.

Abstract: This invention comprises a method and an apparatus for separating solids from fluids in fluids containing high total suspended solids and where the solids are of a broad particle size including ultra fine particles. A fluid volume is passed through a filter element thereby separating the solids from the liquid. The solids deposited on and in the filter element are cleaned from the filter element by a continuous backwashing process using pressurized filtered fluid in excess of the fluid pressure of the fluid on the intake side of the filter. The rate at which backwashing occurs and the pressure of the pressurized filtered fluid used in backwashing is increased when the pressure differential between the intake and outlet volumes increases.

Abstract: This invention relates to a backflushing filter, particularly for filtering lubricating oil. Filter candles 22 which are open at both ends 24, 34 are disposed around a rotary shaft 1 in the filter housing 11, 12, the interior space of which filter candles can be acted upon in filtration operation by a sludge which flows into the backflushing filter 10. A cleaning device is moved in conjunction by means of the rotary shaft 1, and comprises an upper flushing cock 27 and a lower flushing cock, which communicate with an outflow valve via the rotary shaft 1, for cleaning the filter candles 22′ during a backflushing operation. The upper flushing cock 27 is offset by an angle in the direction of rotation in relation to the lower flushing cock 37.

Abstract: Method and arrangement for filtering particles out of a liquid, in which the liquid containing particles is supplied to a sedimentation tank (12), and the liquid is made, by means of hydrostatic liquid pressure prevailing in the tank, to flow through a filter member (18) on the shell surface of a drum (14) mounted in the tank (12). When the liquid in the tank has risen to a predetermined level above the drum (14) as a result of clogging of the filter member (18), cleaning of the filter member (18) in situ in the tank is initiated.

Abstract: A precoat renewal system for a filter, such as a disc filter. The renewal system includes a plurality of nozzles coupled to spray piping and valving with each nozzle being positioned for spraying an area of one side of a disc. The nozzles and at least a portion of the spray piping is movable such that the nozzles may be displaced relative to the discs. The nozzles and piping are arranged in groups or zones with each zone covering a specified percentage of the discs in the filter and each zone representing about 40% or less of the surface area of the filter media of the discs in the filter. Each zone is configured such that high pressure fluid may be supplied to that particular zone for removal of a precoat layer on the disc. The system may be configured so that other zones may be concurrently washed with a lower pressure fluid. The zones may be sequentially or otherwise segmentally provided with high pressure fluid until the precoat layers of each respective zone have been removed and renewed.

Abstract: A shear separation system or method uses shear lift forces and permeate drag forces to separate substances having a size less than a predetermined separation size from substances having a size greater than the separation size. The balance of the drag forces and lift forces affects a predetermined separation size in that the balance of forces reads the transmembrane passage of substances larger than the separation size yet allows substances smaller than the separation size to pass through the permeable membrane. The shear separation device, method and system can be employed to separate or concentrate from a process fluid substances larger or smaller than the predetermined separation size.

Abstract: An apparatus for removing solids from a liquid/solid mixture disposed in a tank and rising to a mixture level, the apparatus including a suction assembly defining a suction opening, the suction assembly linked to a vacuum that causes suction at the opening, a support assembly formed about the suction surface including first and second essentially circular housing walls having wall edges and a filter belt loop sealed to the edges and sized such that the belt is slack and subject to deformation between the edges, a belt section disposed to cover the suction opening and a processor controlling a motivator to periodically alter belt position with respect to the suction opening.

Abstract: A vacuum filter includes a cylindrical filter drum 12 having both a perforate section 14 and an imperforate section 16. The drum is positioned in a tank 20 so that the imperforate section is oriented upwardly therein. A level controller is provided to maintain the level of contaminated fluid below the top of the imperforate section but above the perforate section. A filter belt 54 wrapped around the filter drum is repositioned by rotating the drum when the differential pressure between the interior and exterior of the drum reaches a predetermined value. The inlet ends 35 of the suction pipes 34 are continuously positioned at the lowest point of the drum so that the pump does not lose suction when the drum is rotated thereby facilitating continuous filtration of the contaminated fluid through the vacuum filter.

Abstract: A filter device for filtering plastic melts includes a filter wheel having cavities which are covered by screening elements. A pressure sensor is provided in a melt inflow line upstream of the filter wheel. A pressure sensor is also provided in a melt outflow line downstream of the filter wheel. The pressure sensors measure the pressure drop across the filter. The melt inflow and outflow lines are connected to a melt channel in the filter device, respectively. A melt return line is in connection via a pump and a discharge line with a backflushing slot. The discharge line is connected to an accelerator for increasing pressure in surges. A further melt return/discharge line is connected via a 3-way valve and a return line to the melt inflow line or to a disposal line.

Abstract: Described is a continuous liquid filtering apparatus having a preliminary filtering chamber 9, a filtering chamber 3, a filtered liquid chamber 12, and an electromechanical cleaning system. In operation, after entering inlet 1, liquid passes through coarse screen 2 into the filtering chamber 3. The liquid then passes through a multi-layer sintered filtering element 4 before exiting the apparatus through the outlet 6. The electromechanical cleaning system includes a hollow connector unit 10 having dirt suctioning members 5 and spraying nozzles 11 for cleaning the sintered filter element. The cleaning system is activated whenever the liquid differential pressure exceeds a predetermined valve indicating that the cylindrical filter requires a cleaning treatment. The spraying nozzles 11 are in fluid communication with the filtered liquid chamber 12 via booster pump 13.

Abstract: The invention provides a filtration apparatus for filtering and regenerating a machining fluid. The filtration apparatus includes a dirty tank for receiving the machining fluid and a clean tank fluidly connected to the dirty tank. A filter is provided between the dirty and the clean tanks for filtering the machining fluid which flows from the dirty tank into the clean tank. A conveyer mechanism is provided in the dirty tank for conveying the sediment of particles separated from the machining fluid in the dirty tank. A filter cleaning device are provided for cleaning the filter. The filter cleaning device includes a nozzle bar which is provided in the clean tank for rotation within a plane parallel to the filter means. The nozzle bar directs the machining fluid in the clean tank onto the filter means to blow the particles off the filter means into the dirty tank.

Abstract: A reciprocating power sprayer for cleaning a rotating cylindrical wastewater screen of the type formed of tubular perforate wedgewire. The spray is reciprocated on an elongated pneumatic cylinder which is arranged in parallelism along the cylinder wastewater screen. Controls are provided for automatically controlling the reciprocation of the spray.

Abstract: A first pump collects used slurry which is employed for a CMP technique. A new slurry supply device supplies new slurry having a concentration higher than a concentration of the used slurry, to the used slurry. A sensor measures a concentration of recycled slurry produced by mixing the used slurry with the new slurry. The new slurry supply device stops supplying the new slurry, in a case where the concentration which the sensor measures is equal to or above a predetermined value. A second pump supplies recycled slurry onto a polishing stage, after the used slurry is completely recycled.

Abstract: A filter has a filter housing. An adjustable support couples a filter element to the filter housing. A first end of the adjustable support is fixedly connected to the housing. A movable portion of said adjustable support is coupled to said filter element. The movable portion is opposite the first end. The movable portion is disposed in the throat of the filter element. The filter element occupies a fluid intake position when said movable portion is in a first position. The filter element occupies a bypass position when said movable portion is in a second position.

Abstract: A filtration apparatus is provided, of the type that includes a stack of rapidly rotating membrane packs (32, FIG. 2) and a stack of stationary separator elements (36A, 36B) interleaved with the membrane packs to leave thin gaps (40A, 40B) between them, which obtains the advantages of both series-connected and parallel-connected systems. A feed conduit (82) connects the radially outer ends (110) of the gaps, to carry feed fluid into and out of each gap. The rapidly rotating membrane packs cause radially outward flow (94, FIG. 5) near their surfaces, which causes radially inward flow (102) near the surfaces of the stationary elements, to cause fluid flow radially inwardly and then outwardly through each gap. The system is operated so particles (111, FIG. 6) of the feed fluid can build up on the rotating pack surfaces (92) only to a thickness that is much less than one-half the thickness (116) of the gap, before commencing any procedure to clean the membrane pack surfaces.

Abstract: The filter intercepts dirt emanating from a molten-polymer extruder. The filter is clamped between perforated support plates, and a rotor sweeps the holes in the upstream plate. The rotor defines a cavity which communicates with a small sector of the holes at any one time. The cavity is openable to drain, via a valve. The melt is under high pressure, to which the cavity is exposed. The rotor is rotated by a drive-shaft, and the drain is located co-axially with the drive-shaft.

Abstract: A self-cleaning filter is provided for filtering particulate from a fluid flow stream such as water used in an irrigation system or the like, wherein a segmented filter element is backwashed or flushed clean in response to cyclic on-off supply of fluid. The self-cleaning filter comprises a filter housing having inlet and outlet fittings for in-line connection along a water supply conduit at a location downstream from a system on-off valve. The segmented filter element is supported within the filter housing, with a first filter segment aligned with an inlet port for filtering water. When the water supply is turned on, filtered water passing through the first filter segment initially backwashes through a second filter segment with increasing line pressure to flush prior-collected particulate thereon through a flush port. When the line pressure reaches a predetermined level, a normally open and pressure responsive flush valve closes the flush port.

Abstract: A system for filtering fluids uses the pressure differential across a filter element between an internal filter volume and an external filter volume to control the rate of fluid flow through the filter element. The internal filter volume communicates with a backwash volume contained in the external filter volume. The backwash volume may be movable relative to the filter element to clean accumulated filtrate from the filter element through backwashing. By increasing the pressure in the internal filter volume, the rate of backwashing can be increased while the rate of fluid flow into the internal filter volume is decreased. Particularly when the filter element becomes clogged, damage to a filter caused by an excessive pressure differential across the filter element may be decreased.

Abstract: A uniform area shower for use with a disc filter. The disc filter includes at least one disc and moving showers that periodically remove a precoat layer of solids from the surface of the disc. In one embodiment the uniform area shower comprises a oscillating shower that is pivotly mounted and travels radially over the disc. In an alternative embodiment the uniform area shower comprises a traversing shower that mounts to a carriage and travels radially over the disc. Each shower includes a controller controlling the drive mechanism to vary the speed of transport of the shower across the surface of the disc such that time spent by the shower cleaning the disc at each radial cleaning position is generally proportional to the radial distance of the cleaning position from the center of the disc so that a wash liquid is applied to a uniform area of the interior and exterior of the disc.

Abstract: A self-gush-cleaning filter device comprises a filter casing (1) provided with an inlet passage (a) and an outlet passage (d), a screen (11) disposed within the filter casing (1) so as to slide along the inner surface of the filter casing (1) in the flowing direction of a fluid, a foreign matter ejecting opening (15) being formed between the screen (11) and the inlet passage (a). A drive shaft (4) for driving the screen (11), a screen driving unit (3) for driving the drive shaft (4) so as to move the screen (11) quickly in a downstream direction in which the fluid flows from the inlet passage (a) toward the outlet passage (d) and to move the screen slowly in an upstream direction. An outlet shutoff valve (14) is disposed in the outlet passage (d) of the filter casing (1). The screen driving unit (3) is actuated after closing the outlet shutoff valve (14) to move the screen (11).

Abstract: A high pressure automatic lime mud precoat filter cake heel removal system provides for steady kiln operation. The system provides multiple points of washing located such that washing of the entire filter can be accomplished in a short period of time. Each washing point comprises preferably two nozzles at predetermined angles to optimize washing of the filter media. The system is reciprocatively driven by a fractional horsepower gear motor connected to a torque converting coupling which is, in turn, connected to a threaded jack shaft or lead screw. The gear motor is controlled by a dual speed reversing variable frequency drive; limit switches automatically control cycling of the system in conjunction with logic circuits and sensors. This system is variably controlled so that cycle times may range optionally from approximately one to approximately five hours in length.

Abstract: The present invention is directed to a filter apparatus for filtering out suspended solids from liquid that is passed through filter material supported within a tank. The invention is also directed to a method of cleaning the filter material while the filter material remains inside the tank. The disclosed apparatus and method facilitates the removal of solids which are deposited on the filter material during the filtering operation, as well as biogrowth and other foreign matter. The cleaning method utilizes a suction generating device, such as a pump and associated suction heads, for backwashing the filter material. The cleaning method also utilizes a device for directing a liquid stream of a chemical cleaning solution at high velocity to the filter material thereby chemically washing the filter material and dislodging filtered solids and other foreign matter therefrom.

Abstract: The invention pertains to a tube filter device for the filtration of beer.In order to ensure a dependable, simple, time-saving and water-saving purification in a device of this kind, there is an inlet line underneath the tube filter with at least one rotary spray arm having upward directed spray nozzles, wherein the spray nozzles are arranged so that they generate concentric spray circles upon rotation of the spray arm, said circles are located essentially between the tube filters, and that also a drive unit is provided for rotating the spray arms.

Abstract: The present invention relates to a filter unit, and a filtering system using the filter unit. The filter unit includes a housing having a longitudinal axis and an inlet and outlet for fluid containing solid contaminants and a back-flush inlet and back-flush outlet for cleansing fluid. This housing contains a substantially cylindrical filter element which has a longitudinal axis coincident with the longitudinal axis of the housing. The filter element has disposed within it a conduit, adapted to be opened to atmospheric discharge, having a longitudinal axis coincident with the longitudinal axis of the filter element. The conduit also has disposed along its surface cleansing members, which extend from the conduit to the filter element and have apertures to allow the cleansing fluid to flow through the members and into the conduit.

Abstract: A filter assembly has a cylindrical filter element immersed in the fluid to be filtered, and which fluid normally flows radially inwards through the filter element and is thereby filtered. When the filter element is to be cleaned by backflushing, fluid flowing inwardly through the filter element is impelled by a rotating pump vane which directs fluid within the filter element outwardly at relatively high through the filter element thereby dislodging debris which may have adhered to the exterior of the filter element.

Abstract: An endless filter chain for filtering a liquid, such as sewage, which flows along a drainage duct is provided. The filter chain comprises strainer elements and connecting links interconnected to allow the strainer elements to pivot about respective axes of the connecting links while maintaining a small clearance between the leading edge of each strainer element and the trailing edge of the respective adjacent preceding element while the filter chain is trained about an upper and a lower turning roller. the filter chain does not comprise conveyor chains and the strainer elements can be sized to a width where they cover practically the entire width of the drainage duct. A method and an apparatus for filtering liquid as well as a strainer element and a connecting link are provided.

Abstract: A pair of strainer systems in parallel provide continuous filtration of solids from an influent stream. In influent strikes a filtration medium in the form of a porous membrane at an angle other than the perpendicular to create a washing action to remove filtrate from the surface of the porous membrane. As filtrate builds up on the surface of the porous membrane, the pressure differential across the strainer increases to a first setpoint which activates a motor which drives a wiper blade to scrub filtrate off the surface of the porous membrane. Ultimately, solids build up within the pores of the porous membrane to a point where the wiper blade is no longer effective to lower the differential pressure across the strainer to an acceptable level. When this happens, a differential pressure signal isolates the operations strainer and places the standby, parallel strainer in service. Filtrate scrubbed from the surface of the porous membrane is collected in a sump and occasionally drained or flushed from the system.

Abstract: The invention provides a multi-stage apparatus for continuous waste water filtration, comprising a first tank provided with a waste water inlet pipe to supply waste water containing suspended solids to the tank, means for adding a coagulant to the waste water and an outlet pipe, a second tank receiving the mixture of waste water and coagulant from the outlet pipe, the second tank being sufficiently large to allow larger suspended solids to settle and being provided with a lower, openable port for discharge of the settled solids and having an upper weir for discharge of partially-cleared water, a continuously-driven, non-taut perforated belt, having a surface positioned to receive, at a first location, a stream of the discharged, partially-cleared water, the belt perforations being sized to enable the passage of clear water therethrough while retaining fine and coagulated solids on the surface for subsequent discharge at a second location, and the belt being non-taut to form a trough for retaining a body of wa