Abstract: Filter element, formed by a supporting body with a filtration part and a connecting part extending therefrom, in which the filtration part has the form of a flat ellipse or a flat rhomb, from which the connecting part gradually extends to a rounder shape, while over the supporting body a filter bag has been applied which at the open end has been fastened onto the connecting part by means of a clamp device.

Abstract: The cross flow filter method includes an open tank having a first liquid retaining section, a second filter retaining section and a third solids collecting section in fluid communication with each other. A filter assembly is retained within the second section and includes a filter panel having a generally vertically disposed porous media surface. Filtrate is removed by applying very low vacuum pressure in communication with the filter panel such that filtrate is drawn through the pores of the filter media surface at a flow rate Q.sub.out. Fluid to be filtered is simultaneously cross flowing vertically downward across the filter media surface at a flow rate Q.sub.x, such that the horizontal velocity V.sub.h of fluid drawn through the filter media surface is very slight with respect to the vertical velocity V.sub.v of the cross flowing unfiltered fluid.

Abstract: A cross flow filter apparatus and method uses an open tank having a first liquid retaining section, a second filter retaining section and a third solids collecting section in fluid communication with each other. A filter assembly is retained within the second section and includes a filter panel having a generally vertically disposed filter membrane surface, preferably with submicron pores. Filtrate is removed by applying low vacuum pressure, in the range of about 5 inches vacuum pressure (Mercury), in communication with the filter panel such that filtrate is drawn through the pores of the filter membrane surface at a flow rate Q.sub.out. Fluid to be filtered is cross flowing vertically downward across the filter membrane surface at a flow rate Q.sub.x, such that the horizontal velocity V.sub.h of fluid drawn through the filter membrane surface is less than the vertical velocity V.sub.v of the cross flowing unfiltered fluid.

Abstract: A fuel filter and method of making same provides an in-tank filter having a novel fitting and seal construction. The filter includes a fabric body and a spacing structure disposed within the body to prevent collapse of the filter and accompanying reduction of or interference with fuel flow. The fitting comprises a first segment disposed outside the filter and incorporating a fuel line receiving aperture and a second, mating segment disposed within the filter. The filter segments are ultrasonically bonded to the fabric such that melting material from the segments flows into the interstices of the fabric and mechanically bonds and retains it within the segments of the fitting.

Abstract: A construction of filter sock which has a panel (1) with two leaves (2,3) of unequal width such that when folded along a foldline (4) the leaves form a double leaf panel with a projecting side (9). The side (9) is folded back along a second fold line (11) over the free side (6) of leaf (2). The sides (6,9) and leaf (2) are secured together by an overlock stitching (13) to form a tube (12). The invention provides a method of making the filter sock.

Abstract: A filtering method in which an object to be filtered and dewatered is brought through a finely porous suction face saturated with liquid, into hydraulic connection with a liquid situated under a negative pressure relative to the object to be dewatered. The filter plate or equivalent and the material to be filtered which adheres to the plate by the liquid suction, are surrounded by a pressure-tight cover. A positive pressure relative to atmospheric pressure is introduced into this cover, by which removal of liquid out of the material to be filtered is intensified. A device for providing such filtration is also provided.

Abstract: In a sector-shaped screen segment for disk filters or thickeners with a folded screen for thickening fiber suspensions comprising a frame, two screen carriers and a screen resting on the outer sides of the screen carriers, manufacture is rendered simpler and less expensive by the frame and the screen carriers forming an integral molded part in which the screen is embedded in the molding process.

Abstract: A fluid filter is disclosed which includes a casing defining a fluid chamber with inlet and outlet apertures to and from the chamber to respectively conduct unfiltered fluid to the chamber and filtered fluid from the chamber. A flow path is defined within the chamber and a filter is interposed in the flow path substantially normal to the direction of flow of the fluid in the chamber. The filter includes a screen having a covering of a filter aid, such as diatomaceous earth, on an upstream side of the screen. The filter is regenerated by reciprocating the screen relative to the casing in a path corresponding to the path defined by the direction of flow.

Abstract: A disk filter, including a plurality of rotatable, axially spaced annular filter disks (6:1-6:11) adapted to be partially immersed in a liquid or a suspension which is to be filtered. Each filter disk comprises a plurality of filter elements 6:1a-f . . . 6:11a-f) which are in communication with axial filtrate conduits (2a-2l) arranged at the outer peripheries of the annular disks for discharge of filtrate. For increasing the flow speed of the filtrate in the axial filtrate conduits these slope downwards in the flow direction. This has been achieved in that a filter element (6:1a) of a filter disk (6:1b) is displaced relative to the filter element (6:2a) of the filter disk (6:2) connected to the same filtrate conduit (2a) and being the following filter disk, counted in the flow direction in the axial filtrate conduit, so that the first mentioned filter element is in advance of the later mentioned filter element, as counted in the direction of rotation.

Abstract: A filter bag for a filter section (1) which is one of a plurality of filter sections assembled to an annularly shaped filter disk for a rotating filter. The filter bag is shaped to conform to the configuration of the filter section and is adapted to be pulled over it and to be closed. A strip (9) is fastened in advance to the outlet end (7) of the filter bag and is provided with at least one filtrate outlet opening (10).

Abstract: A filter unit using a bump-type filter is disclosed. Briefly stated, a chamber has a fluid inlet conduit so that contaminated fluid, upon entering the chamber, is directed upwardly towards filter tubes and downwardly towards the bottom of the chamber. The fluid flow is diverted during startup so as to be directed only downward. A bump handle is disposed between two fluid outlet conduits such that one is opened and the other is closed and the reverse when the bump handle is in a first or second corresponding position. A plurality of microswitches are utilized so that the pump is not enabled during bumping or when a dump valve is open, but is enabled during system operation or startup.

Abstract: A system for continuously or periodically flushing collected particles from filter leaf assemblies without interrupting the filtering operation is disclosed. The filter leaf assemblies are constructed from a pair of like grid-like filter media support panels mounted in spaced parallel relationship within a rigid rectangular peripheral frame. Sheets of filter media overlie the outer surfaces of the support panels and are fixedly sealed to the frame around the entire periphery of the panel. One side of the frame is fixedly mounted to an outlet pipe whose interior communicates with the space between the support panels via mating slots in the pipe wall and frame. Two filter media attachment arrangements and two frame to pipe mounting arrangements are disclosed.

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: The invention relates to an apparatus for separating contaminants comprising a tubular filter body (12) having an inner flow space (18) which is separated by a filter layer (14) from an outer flow space (20). The one end face of the filter body (12) is closed and the other end face comprises an opening. The inner flow space (18) has a substantially uniform cross-section over its entire axial length and is in flow communication on the one hand through the filter layer (14) with the outer flow space (20) and on the other hand through the end-face opening with an outside space. In the inner flow space (18) an element (30) is arranged for conducting the flow through the filter layer (14), which is characterized in that said element (30) for conducting the flow from or to the filter layer (14) is gradually tapered in its cross-section from the sealed end face (16) to the end-side opening (22) of the inner flow space (18).

Abstract: A filter segment disc of a segment filter comprises a support and drainage plate with slots radiating from the filter hub toward the filter edge. The slots are preferably of arcuate plan form and configured to provide a substantially uniform fluid flow over the filtering medium of the filter segment, reduce residence time of filtrate in the filter, eliminate dead spots in the flow, and facilitate cleaning of permanent filters. A filter support spacer may be provided adjacent the filtering surface to aid in support and positive spacing of the disc in a filter stack of which the disc may be an element.

Abstract: A filter assembly having a filter chamber. Filter means is disposed in the filter chamber which comprises at least one disc shaped filter assembly. The disc assembly has an upper support disc and a lower aligning support disc. A filter membrane is disposed on the top side of the support disc which has a plurality of primary grooves for receiving a liquid filter through the filter membrane. The aligning support disc fits substantially centrally on the bottom surface of the support disc and is provided with radially extending ribs which form radially extending grooves between. A second filter membrane is placed on the bottom surface of the support disc and overlaps a portion of the aligning disc. The bottom surface of the support disc is also provided with grooves for collection of a filtrate. Axial extending grooves are provided in the support disc for connecting the collection on the top surface with the bottom surface.

Abstract: A plate-type filter cartridge includes a plurality of stacked filtration units; each filtration unit having inner and outer rims, two filtration membranes bonded to opposite sides of the two rims, and a pair of netty members formed of fibrous material contacting a porous support and membranes. The support supports the membrane and is disposed between the membranes; the support being defined by a plurality of spokes and an outer rim.

Abstract: A filter unit using a bump-type filter is disclosed. Briefly stated, a chamber has a split fluid inlet conduit so that contaminated fluid, upon entering the chamber, is directed upwardly towards filter tubes and downwardly towards the bottom of the chamber. The fluid flow is diverted during startup so as to be directed only downward thereby enabling precoat of the filter element. Two tube sheets are utilized with incoming fluid in the vertically upward inlet conduit forcing incoming contaminated fluid to be deposited between the two tube sheets thereby. During operation contaminated fluid flows upwardly and downwardly towards the filter tubes so as to prevent disturbance of filter tubes as a result of turbulence in the chamber.

Abstract: A mesh filter bag fits over a metal support. The bag has opposed edges longitudinally extending along one side of the mesh filtering bag from the bottom of the bag to the top of the bag. A rope extends from the filtering bag bottom along one opposed edge over the top and along the other opposed edge to the bottom. The opposed edges are held in sealing engagement by a tube.

Abstract: A method for manufacturing a microporous plate, a filter plate obtained from the method, and suction drier apparatus utilizing such filter plates. According to the method, a casting mix is introduced into the interior of a gypsum mold whereupon water is absorbed from the casting mix into the gypsum so that a crust remains on the inner surface of the mold. The crust is allowed to develop to an appropriate thickness whereupon the remaining casting mix is drained from the mold. The inner surfaces of the crust are allowed to dry whereupon the interior space defined between opposed crust wall portions is filled with a granular material which preferably has the same composition as the crust material. A filter plate comprises a pair of opposed suction walls defining an interior space between them which is filled with a granular material. The suction drier apparatus includes at least one of the filter plates which is mounted to be moved into and out of a basin or the like in which material to be dewatered is present.

Abstract: A filter leaf cleaning system for use in a suction-type filter apparatus having a tank to receive polluted liquids to be filtered or clarified includes a cleaning system header connected to a filtrate discharge conduit for diverting a portion of filtrate flow into the cleaning system, valve means connected to the cleaning system header for controlling filtrate flow into the cleaning system, a dispersing conduit connected to the cleaning system header adjacent a particulate-filtering surface of each filter leaf and having an opening for directing the filtrate flow across the particulate-filtering surface to flush particulates from the surface toward a solids collecting section of the tank housing the filter leaf. In addition, or in the alternative, the cleaning system may employ a membrane wiping member for sweeping movement across the particulate-filtering surface to brush residue or particulates from the surface.

Abstract: A filter apparatus is provided comprising a number of cylindrical candle filters, each of which contains a displacement body forming a space of uniform width between itself and the candle filter. The filter material of the candle filter is supported by a cylindrical supporting body which has passages through which a plastic melt to be filtered can flow. A number of filter apparatuses can be arranged on concentric circles on a cylindrical filter housing so as to minimize the dwelling time of the plastic melt flow through the filters and to minimize the pressure loss over the length of the filters.

Abstract: Injection-molded intake-water filtering apparatus designed for use with electric power generating stations and the like, comprising a rectangular elastomeric grid in which the number and spacing of the longitudinal elements are both adjustable. The lateral spacing between the longitudinal elements is established by cylindrical sleeves through which pass transverse rods which bind together the longitudinal elements to form the grid. The elastomeric material used is of a hardness, strength, and elasticity necessary to resist the large forces to which the trash rake is exposed and sufficiently smooth that ice-nucleating centers and marine-growth anchors are effectively absent on the surface of the finished grid.

Abstract: A reverse osmosis water purification module has an enclosed cylindrical housing in which at least twelve purification elements are mounted in a uniform, spaced parallel fashion. Each element consists of a long flat member having a thermoplastic sheet backing formed into a slightly curved cross section and having a semi-permeable membrane disposed thereon. The backing has three-dimensional porosity for purified water such that water passing through the membrane portion of the element travels along the backing member to an end. The ends of the module are mounted in a collection manifold which is sealed off from the remainder of the housing interior. A method of manufacturing the elements continuously is also provided wherein a continuous length of flexible backing material is fed sequentially through a heater, a forming die to impart a curved cross-section to the backing material, an extruder wherein membrane forming fluid is extruded around the periphery of the backing, a chill bath and a heating bath.

Abstract: A filter apparatus for removing plankton out of fresh or sea water containing the plankton. The filter apparatus comprises a filter housing provided with a partition plate having a plurality of through-holes thereby to partition the housing into a non-filtrate chamber and a filtrate chamber. A plurality of filter elements, each having open top end, a filter portion and non-filter portion, which are fitted in the through-holes of the partition plate to protrude the open top ends into the filtrate chamber. Plankton in the water are concentrated at the non-filter portion disposed near the partition plate and removed through an opening provided at a portion of the non-filtrate chamber near the partition plate.

Abstract: The invention relates to a filter means for filtering gases, liquids or similar filtering media, preferably for process engineering plants, e.g. those for the foods and drinks industry, such as for compressed air preparation, particularly in sterile operation, optionally under overpressure conditions and/or at high temperatures, in which there is a segmental construction, formed by essentially circular filter elements, against which a flow can take place from the inside and outside, together with interposed, disk-shaped filter material and in which the entire edge area of the filter material sealingly cooperates with the filter elements.

Abstract: A polymer filtering apparatus (1) is used to filter a molten polymer in a step of extruding a molten polymer to manufacture films and fibers. A plate type filter medium (4), which is incapable of resisting a filtration pressure, is supported at its rear portion on a liquid-permeable support member (5). Two pieces of filter media (4), (4) of the above-mentioned construction are arranged in opposition to each other so as to form a polymer passage (10) therebetween, and a polymer to be filtered is fed from this polymer passage (10) and through the filter medium (4) and support member (5). The plate type filter medium (4) and support member (5), which are detachably piled, can be separated, and the surfaces thereof can be easily washed. Moreover, the results of washing of both the primary and secondary sides can be inspected visually with ease.

Abstract: Improved filter leaf assemblies are constructed from a pair of like grid-like filter media support panels mounted in spaced parallel relationship within a rigid rectangular peripheral frame. Sheets of filter media overlie the outer surfaces of the support panels and are fixedly sealed to the frame around the entire periphery of the panel. One side of the frame is fixedly mounted to an outlet pipe whose interior communicates with the space between the support panels via mating slots in the pipe wall and frame. Two filter media attachment arrangements and two frame to pipe mounting arrangements are disclosed.

Abstract: A filter (51) for liquids comprises a filter vat (52) having an inlet orifice (60) for the liquid to be filtered, an outlet orifice (58) for the filtrate, and an evacuation orifice (66) for solid particles, together with filter elements comprising filter medium cloths disposed vertically around filter leaves (18) inside said vat between said inlet and outlet orifices. Said cloths (12) are in the shape of elongate pockets (16) threaded freely over said leaves (18), said leaves being provided with longitudinal drainage channels (32), said pockets having openings (19) in communication with said outlet orifice (58), and said filter leaves (18) being suspended beneath supports (20) which are fixed inside said vat (52), with said leaves being free to rock sideways from their supports.

Abstract: Filter chambers composed of two adjacent filter disks are attached to a drum-like filtrate collection chamber and are adapted to rotate therewith. The filtrate penetrates the filter disks and enters the collection chamber and thereafter exits the collection chamber through a collection space. The collection space is sealed from the trough by means of a rotating seal. The suspension inlet is provided on a sidewall of the trough and the suspension outlet is provided on the opposite wall of the trough. The disk concentrator serves to remove filtrate from aqueous suspensions containing fibrous components.

Abstract: A cross-flow filtration device which separates a feed stock into filtrate and retentate, including a structure of porous material which defines a plurality of passageways extending longitudinally from the feed end of the structure to a retentate end, and a number of filtrate conduits within the structure for carrying filtrate from within the structure toward a filtrate collection zone. The filtrate conduits provide paths of lower flow resistance than that of alternative flow paths through the porous material, and the structure is constructed such that the filtrate conduits are distributed among the passageways to provide low pressure drop flow paths for filtrate flow from the passageways through the porous material to nearby filtrate conduits. The cross-flow filtration device can also be utilized as a membrane support for a device for cross-flow microfiltration, ultrafiltration, reverse osmosis, gas separations or pervaporation. Also disclosed is a method of making such a cross-flow filtration device.

Abstract: A diatomaceous earth caking filter element includes a first elongated tubular manifold having a slot therein and a suction coupling formed thereon for drawing a liquid from said first manifold. A second elongated tubular manifold has a slot therein and a plurality of hollow pipes connected between the first and second manifolds with one end of each pipe extending into the first manifold through the slot therein and the other end of each pipe extending into the second manifold through the slot therein. Each pipe is held by the slot edges of each manifold extending into an annular groove on each end of each pipe. A filter cake screen covers both sides of the plurality of hollow pipes for catching a filtering medium, such as diatomaceous earth, thereon for filtering liquid passing therethrough, so the liquid can be drawn through the filter medium and filter screen into the first and second manifolds and out the suction coupling.

Abstract: A precision filter for accomplishing filtering of precision of submicron order. A filter element of the filter consists of a plurality of superposed disc-shaped annular support members for filter membranes. Each support member has a radially outwardly extending intermediate section located between an annular boss section and an outer frame section. The intermediate section is formed on its upper and lower sides with a plurality of gently winding elongate ridges and largely winding elongate ridges. Each largely winding elongate ridge extends from the boss section to the outer frame section, but each gently winding elongate ridge located between the two largely winding elongate ridges is separate from the boss section thereby to form two elongate winding grooves which are joined and continuous to a central opening of the boss section.

Abstract: An improved triangular filter cartridge and apparatus is provided comprising a generally cylindrical vessel having a plurality of generally triangularly shaped filter cartridges disposed therein. Each triangular filter cartridge has one of its substantially flat sides slightly spaced apart from and in direct facing relationship with the inner surface of the vessel, whereby a greater number of triangular filter cartridges can be compactly disposed within said vessel to increase the filtration capacity thereof. Each filter cartridge includes a passage that is triangularly shaped in a plane perpendicular to the axial direction.

Abstract: A filter element for use in a filter apparatus comprises a plurality of cylindrical filter units coaxially aligned end-to-end to form an integral tubular structure, a top end cap and a bottom end cap on the upper opening and the lower opening, respectively, of said tubular structure, and a cylindrical displacement member disposed coaxially within the tubular structure with a small clearance therebetween.

Abstract: For the separation of a slurry into cake and water, a set of rotary filter discs are mounted on a hollow shaft at constant longitudinal spacings and in positions of registry with one or more rows of bores in the hollow shaft. Each filter disc has a filter cloth or like filter element enveloping a carrier disc, so that the water that has passed the filter cloth flow into the bores in the hollow shaft through a gap between the carrier disc and the hollow shaft. Arranged alternately with the filter discs are baffle plates which also are each enveloped by a filter cloth for the separation of water from the slurry. Each filter disc has one or more flow accelerating members mounted astride the peripheral edge thereof. The flow accelerating members create cavities in the slurry with the rotation of the filter discs, thus facilitating the flow of the slurry between filter discs and baffle plates.

Abstract: A filter apparatus for clarifying liquids or gases includes a tank having a rigid horizontally disposed tube sheet contained therein for supporting a plurality of elongate tube filter elements. Each tube filter has an enlarged hub at one end configured with an exterior annular beveled surface. The tube sheet has apertures through which the tube filters extend and each aperture is configured with an interior annular beveled surface serving to cooperate with the beveled surface of a tube filter and prevent its downward movement within the tank. A gasket is interposed between the beveled surfaces of the tube sheet aperture and tube filter, and pins extend at an angle through the tube sheet into the hub of each filter for securing the filters in compressed engagement with the gaskets. The arrangement of the beveled surfaces and pins is such that the filter tubes remain sealed to the tube sheet regardless of the effects of differing coefficients of thermal expansion as between the filter tubes and tube sheet.

Abstract: A filtration apparatus including a filtration module having an axially stacked plurality of filter membrane sheets with the module defining a stack of fluid flow chambers having multi-edged perimeters and disposed on opposite sides of and substantially coextensive with each membrane sheet. Also defined by the module are a plurality of feed passages communicating with alternating ones of the chambers adjacent first axially aligned edges thereof, a plurality of retentate passages communicating with the alternating chambers adjacent to second axially aligned edges thereof opposite to the first edges, and a plurality of filtrate passage means communicating with other ones of the chambers between the alternating ones thereof and with the filtrate passage means entering the other chambers adjacent to either the first or second aligned edges. Also included in the apparatus are a base frame and a pair of parallel plates supported by the frame and movable thereon relative to each other in directions normal thereto.

Abstract: An improved triangular filter cartridge and apparatus is provided comprising a generally cylindrical vessel having a plurality of generally triangularly shaped filter cartridges disposed therein. Each triangular filter cartridge has one of its substantially flat sides slightly spaced apart from and in direct facing relationship with the inner surface of the vessel, whereby a greater number of triangular filter cartridges can be compactly disposed within said vessel to increase the filtration capacity thereof.

Abstract: A rotary disk filter element for a beverage filter for biological filtration. The filter element includes a closed base plate that is in the form of a ring-like member and on which is supported a filter fabric, with a support fabric being interposed between the base plate and the filter fabric. The filter fabric is secured to the base plate between an outwardly disposed retaining member and an inwardly disposed collar member. The collar member is provided with a supply opening for a wash fluid, especially a water/air mixture that is flushed through the filter fabric, counter to the direction of filtration, for removing filter residue for the general cleaning of the filter fabric. The filter fabric is secured to the base plate and to the support fabric at a plurality of point locations. This divides the free support or clamping lengths of the filter fabric into a number of relatively short regions that prevent the filter fabric from being overstretched and bulged during flushing.

Abstract: A depth-type filter cartridge comprises an elongated fluid-conducting core, and a plurality of filter cells mounted generally parallel to one another along the length of the core. Fluid to be filtered passes from the exterior into the interior of the cells through a filter medium, and then from the interior of the cells into the core. Support for the filter cells to prevent distortion or damage when used under extreme conditions is provided by external filter cell separators which coact with the cells and are mounted radially about the core between each pair of adjacent cells.

Abstract: A filtration sector for making up a filtration disc comprising a rigid frame imparting its shape thereto, supports for filter cloth within the frame and a member for connection to a hollow driveshaft of a rotary filter, said shaft containing liquid and gaseous fluid collectors, which is characterized in that said sector is of an increasing internal thickness from its peripheral end to its end in the vicinity of the hollow driveshaft (2).

Abstract: A wire cloth for a filter has a twill lace weave which is formed in patterns alternating in the direction of the twill line. The alternation is provided substantially in the region of weft wires. At least one intermediate weft wire is introduced in the region of discontinuity of the twill line whereby the position of the weft wires in each pattern of the twill weave is fixed and a mesh size in the weave can be accurately determined.

Abstract: To adapt a disc filter element of a rotatable disc filter to varying flow conditions the fluid tight filter element body (11,12) is provided with openings (34-39) the number of which is increased with increasing flow capacity through the filter means (17) of the filter element. Also, with increasing flow capacity the openings of the increasing number of openings are located at increasing distances from the vacuum connection (29) of the filter element. In order to prevent filtrate from entering portions of the interior of the filter element body beyond the most distant opening (39), as seen from the vacuum connection (29), such portions of the interior space of the filter element body are sealingly shut off from the remainder of the interior space.

Abstract: A method for improving the operation of a disc filter used for the filtering of fluids containing solid matter such as fibers. Known filtering methods have the drawback that the rate of water exhaustion is limited, because a vacuum tends to be created inside the sectors when the filtered fluid is drained by suction from the central channel of the disc filter. This drawback is an obstacle to increasing the speed of rotation and therefore to increasing the capacity of the disc filter. With the method of the present invention, this problem is solved by providing the disc filter with a means of admitting ambient air into the disc sectors and the central shaft channel and/or with equipment for blowing air into the sectors and the channel to remove the filtered fluid from them.

Abstract: In a rotating disc filter for dewatering a suspension comprising filter discs (3) divided into a plurality of disc sectors (4), the discharge of filtrate from each disc sector takes place through an axial filtrate channel (7). Each filtrate channel is at the side wall of the filter connected to a fall pipe (8) which rotates with the channel and extends in radial direction relative to the filter shaft (6). Preferably each of said filtrate channels is at said side wall provided with a pre-filtrate outlet (10).

Abstract: Drainage mat comprising three-dimensional openwork covered on at least a major surface with a water permeable fabric having a permittivity from 0.2 seconds.sup.-1 to 2.0 seconds.sup.-1 and exhibiting a dynamic permeability after 10.sup.6 loadings of at least 10.sup.-4 centimeters per second.

Abstract: A filter candle element which is mounted in depending manner in a pressure container has a support body and a filter tissue which covers the support body and has at least one impermeable portion so as to prevent the depositing of a continuous filter cake. Through provision of a plurality of impermeable portions, the filter cake is divided into several pieces which do not obstruct their removal. The impermeable portions are obtained by spraying of synthetic material onto the filter tissue. These filter candle elements are especially suitable for alluvial filters of large dimensions.

Abstract: A rotary filter, formed by a number of annular filter discs (1), mounted substantially parallel on a driving shaft, for the uptake and dewatering of fiber suspension from a container, fiber cakes (5) being formed, adhering to the outer sides of the filter discs (1), is provided with spraying nozzles (3), arranged in a removal zone for removal of said fiber cake (5). The invention consists of supporting elements (4) provided in the removal zone for supporting the fiber cake (5) in its upper loosened part and to prevent it from folding out from the filter disc (1) during the removal process.

Abstract: The filter apparatus has a plurality of filter cylinders each formed of a plurality of filter elements and a blind cylinder is provided between a support plate for supporting the filter cylinders and the uppermost filter element of each filter cylinder, in order to prevent a liquid to be filtered from passing a region of each filter cylinder where the surface of the liquid is moved vertically.