Abstract: A device for cleaning a fluid comprises at least one set of a first membrane cloth and a second membrane cloth, each being permeable to water over substantially their entire length. The membrane cloths are held taut, substantially parallel to one another in a frame delimiting between them a movement path for fluid. The cloths are displaceable with respect to one another between a first position, in which the mutually facing surfaces substantially touch one another, and a second position, in which the cloths lie at a distance from one another and the width of the movement path for the fluid is greater than in the first position. At least one of the cloths, on the side which faces towards the adjacent cloth is provided with grooves or webs for the purpose of forming channels between the cloths in the longitudinal direction of the cloths, in the first position.

Abstract: Screen apparatus comprising a screen (10) which allows fluid to pass through it whilst providing a barrier to non-fluid matter in the fluid. A jet outlet (22) is arranged to direct a jet of fluid across that side of the screen (10) on which such matter would otherwise tend to collect when the apparatus is in use.

Abstract: A filter device has a filter housing, which is intended to contain a liquid to be filtered and in which at least one filter rod is arranged. The filter rod is composed of annular washers, which are arranged in a stack on a core formed with openings and which are so closely packed that particles in the liquid adhere to the periphery of the washers when the liquid is caused, from the outside, to pass between the washers into the core for filtration. The filter device has a gas supply member, which is intended to inject a gas flow into the liquid in the filter housing. In a method of cleaning a filter rod for filtering a particle-containing liquid in such a filter device, a gas flow is injected into the liquid in the filter housing so that a particle sock, which is formed on said filter rod of particles in the liquid, is detached from the filter rod and disintegrated.

Abstract: A spiral wound membrane element allowing back wash reverse filtration at 0.05 MPa to 0.3 MPa is employed for a spiral wound membrane module. Air injection of injecting air of not more than 0.3 MPa into a permeate outlet of the spiral wound membrane module from a pressurized air feeder through a pipe, back wash reverse filtration with permeate and flushing with raw water are performed as recovery of a filtration velocity. Another spiral wound membrane module comprises a spiral wound membrane element including a separation membrane having high back pressure strength. Raw water into which bubbles are diffused by an air diffuser is fed to the spiral wound membrane element stored in a pressure vessel. Part of the raw water is axially fed through the spiral wound membrane element, discharged from a raw water outlet of the pressure vessel and thereafter returned to a raw water tank through a pipe.

Abstract: An apparatus using activated sludge for the removal of biological nutrients from a wastewater includes a bioreactor for containing a mixture of wastewater under treatment and activated sludge. The bioreactor is divided into a plurality of serially connected treatment zones and includes a wastewater inlet, a downstream aerobic zone and an upstream aerobic zone between the wastewater inlet and the downstream aerobic zone, the upstream and downstream aerobic zones being separated by an anoxic zone. A method for removal of nutrients from a wastewater includes providing a wastewater to an inlet of a serial, multi-zone, activated sludge bioreactor containing an activated sludge. The bioreactor has a downstream aerobic zone from which water is removed and an upstream aerobic zone between the wastewater inlet and the downstream aerobic zone, the upstream and downstream aerobic zones being separated by an anoxic zone.

Abstract: A system for liquid cleaning a plurality of dirty open-ended cylindrical internal combustion engine paper air filters by subjecting each filter to a cleaning cycle including successive first, intermediate and final cleaning steps. For each step liquid is pumped from a separate tank to spray heads for rinsing a filter at a cleaning station and effluent with entrained contaminants is collected for transfer away from the cleaning station. First step cleaning pumps an unclean liquid previously collected in a first tank as effluent from the intermediate step of a preceding filter cleaning cycle and first step effluent is disposed of away from the system. Intermediate step cleaning pumps a semi-clean liquid previously collected in a second tank as effluent from the final cleaning step of a preceding filter cleaning cycle and intermediate step effluent is collected and transferred as unclean liquid to the first tank for cleaning use during the first stage of the succeeding filter cleaning cycle.

Abstract: A liquid/solid separator system mounted on a mobile cart and connected to a process tank for reducing the rate at which fluids are consumed in manufacturing processes. The system may include automation and also may include a shear stepped screen including tilted wire wedge wires arranged at varying cant angles. The system may include a fine screen basket received in a settling box.

Abstract: A filtration apparatus includes a filter element disposed at a 45 degree angle defining an upper chamber for solids and a lower chamber for liquid. A trough is disposed at the lower end of the filter element. The floor of the trough funnels toward a central drain and an overflow drain is located approximately 8 inches above the trough floor. The lower chamber is provided with a drain for recirculating water to a sprayer above the filter element and is also provided with an overflow drain approximately 8 inches above the floor.

Abstract: A method in treating aqueous feedstream in diverse plant site environments is disclosed for improving filter flux rates, cleaning filter media and prolonging useful operative life of media. In preferred embodiments the method is provided with steps for contacting, reacting, pressurizing and equalizing ozone and feedstream within a central area or multiple areas and sustaining high pressure throughout the system to achieve qualitatively and quantitatively improved permeate products, and reject for recycle. The method and system provide an improved cleaning and processing system characterized by an ozone-concentrated, homogeneous single phase liquid conversion of a generated ozone gas mixture and a feedstream source containing organic and inorganic pollutants. The method improves and monitors ozone oxidizing power and reflecting ORP values, and provides further media cleaning and improved oxidation reactions for attack on pollutants on each cycle/recycle operation.

Abstract: A twist-on renewable filter comprising a one-piece hollow housing, made of polymeric material having a threaded adapter for attachment to a distribution head assembly. The filter housing is fabricated from components that are made of a polymeric material that are fused together to form the one-piece hollow housing. A filter media assembly is rigidly bonded at both ends within the housing. The renewable filter has an infinite life and can be removed and cleaned, for example, by reverse flushing the filter with a cleaning solution. A bypass valve 250 is provided within the filter that is designed to provide full closure for an infinite life. The bypass valve 250 is fully located within the one-piece hollow housing such that it cannot be disabled or tampered with. The bypass valve 250 functions to allow sufficient fluid to bypass the filter media when the filter media has become contaminated and will not permit the full volume of the normal oil stream to be filtered.

Abstract: A system for liquid cleaning a plurality of dirty open-ended cylindrical internal combustion engine paper air filters by subjecting each filter to a cleaning cycle including successive first, intermediate and final cleaning steps. For each step liquid is pumped from a separate tank to spray heads for rinsing a filter at a cleaning station and effluent with entrained contaminants is collected for transfer away from the cleaning station. First step cleaning pumps an unclean liquid previously collected in a first tank as effluent from the intermediate step of a preceding filter cleaning cycle and first step effluent is disposed of away from the system. Intermediate step cleaning pumps a semi-clean liquid previously collected in a second tank as effluent from the final cleaning step of a preceding filter cleaning cycle and intermediate step effluent is collected and transferred as unclean liquid to the first tank for cleaning use during the first stage of the succeeding filter cleaning cycle.

Abstract: A system is provided for withdrawing permeate from a substrate. The exemplary system includes a vessel configured to contain substrate, two or more compartments configured to receive substrate from the vessel and to return a portion of received substrate to the vessel, and a filter positioned at least partially within each of the compartments and configured to separate permeate from substrate during operation of the filter. At least one of the compartments is configured to contain cleaning solution and substantially prevent cleaning solution from contacting substrate in the vessel during cleaning of the filter. The exemplary system is configured for cleaning the filter in situ in at least one of the compartments while operating the filter in at least one other of the compartments. A method for adapting a filtration system for cleaning thereof and a method for withdrawing permeate from a substrate using a filtration system are also provided.

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: A method for removal of solids in a water treatment system having multiple filters, each filter comprising an air backwash system and a water backwash system, comprising a series of steps to enable two filters to be in some stage of the backwash process at the same time thereby reducing the time the filter is out of service. The continuous cycling of the backwash method is characterized by a continuous cycle of backwashing that backwashes two filters simultaneously. The backwashing method requires three steps, an air-only backwash, an air/water bashwash and a water-only or rinse backwash. In this method, as one filter is at the water-only backwash stage, the backwash cycle of a second filter is started so that the second filter is air/water backwashed while the first filter is at the water-only backwashed stage.

Abstract: An aerator for filtering membranes immersed in a tank of liquid has an upper surface having holes for discharging bubbles below the membranes, sides extending downwardly from upper surface for trapping a variable volume of air in communication with holes and an opening to the liquid in the tank below the volume of trapped air so that liquid can be displaced from or enter into the aerator as the volume of trapped air changes. A supply of air is provided to the air space in the aerators alternating between a high flow rate and a low flow rate in short cycles of between about 10 seconds and 100 seconds. Typically, there is substantially no air flow during the period of low air flow. The aerator is sized in relation to the duration and rate of air flow provided during a cycle such that either air flows through the holes throughout each cycle or such that no air flows through the holes during at least part of the cycle such that liquid in the tank may flood the aerator and wash away any accumulated solids.

Abstract: An apparatus for de-watering sludge. A main shaft is rotated about a longitudinal axis at a first rate. A screw shaft coupled to the main shaft is rotated about the longitudinal axis at the first rate. Screw flighting coupled to the screw shaft is rotated about the longitudinal axis at the first rate. A first and second stage drum are rotated about the longitudinal axis at a second rate. Sludge is introduced to a first area defined by an outer surface of the screw shaft and an inner surface of the first stage drum. Moisture is removed from the sludge through a first slot coupled to the first stage drum. The sludge is transported with the screw flighting from the first area to a second area defined by an outer surface of the screw shaft and an inner surface of the second stage drum, the second area being larger than the first area. Moisture is removed from the sludge through a second slot coupled to the second stage drum.

Abstract: A method and apparatus for cleaning candles in a candle filter using a cleaning fluid that flows inside the candle from the side of the filtrate, whereby said fluid is pressed in an opposite direction to the direction of the filtrate from the inside to the outside, through said candles, by a gaseous medium subjected to an overpressure. Water is or can be used as an appropriate cleaning fluid and air is used as a gaseous medium. The prior art teaches nozzle-shaped contractions that are respectively disposed on the outlet end of the candles or deflectors arranged inside the candle at a distance from said contractions, whereby the in-flowing cleaning fluid is deflected towards all sides in the direction of the inner walls of the candles, are provided for distribution of said cleaning fluid.

Abstract: The invention provides a method of recovering filtration residues of blood which comprises filtering blood by a blood filtering device comprising a blood filtering material which is a depth filtering material and a holder which contains the blood filtering material and has a blood inlet and filtrate outlet, after finishing the filtering blood, feeding aqueous liquid to the filtrate outlet to recover the filtration residues accumulated in the blood filtering material.

Abstract: A method of operating a plant for filling containers by moving a liquid such as water through an apparatus with at least one portion for receiving the liquid before it is filtered and at least one portion for receiving the liquid after it is filtered, so that the liquid moves from at least an upper area of apparatus to lower area of the apparatus to be transferred to bottles or other containers.

Abstract: A method of chemically cleaning normally immersed suction driven filtering membranes involves backwashing a chemical cleaner through the membranes while the tank is empty in repeated pulses in which the chemical cleaner is pumped to the membranes separated by waiting periods in which chemical cleaner is not pumped to the membranes. The duration and frequency of the pulses is preferably chosen to provide an appropriate contact time of the chemical, preferably without allowing the membranes to dry between pulses and without using excessive amounts of chemical. In other aspects, such membranes preferably used for filtering water to produce potable water in a batch process are backwashed with a chemical cleaner substantially at the same time as the tank is being drained. The chemical cleaner is optionally supplied in pulses.

Abstract: The invention relates to a method and apparatus for cleaning the filter surface (2, 3) of a filter medium in a suction drier. According to the invention, in order to mark the surface to be cleaned, in contact with the surface to be cleaned there is set a sealing surface (4) that forms an essentially closed space for the surface to be cleaned, and that into said closed space, there is conducted cleaning liquid (7) in order to carry out the cleaning.

Abstract: An apparatus for de-watering sludge. A main shaft is rotated about a longitudinal axis at a first rate. A screw shaft coupled to the main shaft is rotated about the longitudinal axis at the first rate. Screw flighting coupled to the screw shaft is rotated about the longitudinal axis at the first rate. A first and second stage drum are rotated about the longitudinal axis at a second rate. Sludge is introduced to a first area defined by an outer surface of the screw shaft and an inner surface of the first stage drum. Moisture is removed from the sludge through a first slot coupled to the first stage drum. The sludge is transported with the screw flighting from the first area to a second area defined by an outer surface of the screw shaft and an inner surface of the second stage drum, the second area being larger than the first area. Moisture is removed from the sludge through a second slot coupled to the second stage drum.

Abstract: The invention relates to a method and apparatus for cleaning the filter surface (2, 3) of a filter medium in a suction drier. According to the invention, in order to mark the surface to be cleaned, in contact with the surface to be cleaned there is set a sealing surface (4) that forms an essentially closed space for the surface to be cleaned, and that into said closed space, there is conducted cleaning liquid (7) in order to carry out the cleaning.

Abstract: A clarifier for use in treating a liquid containing non-soluble particles in suspension in order to separate these particles from the liquid includes a tank, a liquid supply duct opening into the bottom portion of the tank and an injector for injecting a gas under pressure into at least part of liquid supplied to the supply duct in order to saturate this liquid with the gas and thus to generate gas bubbles as the saturated liquid is subject to depressurization within the tank. The gas bubbles that are so generated adhere to the particles in suspension in the liquid and lift them up to form a floating layer of sludge in the top portion of the tank. A scraper is provided in the top portion of the tank for skimming off the layer of sludge while it is formed. A plurality of plates extend at an angle within the tank above the supply duct. These plates define a set of upwardly inclined channels each having an upper end that is opened and through which the liquid fed into the tank may enter the channel.

Abstract: A method of separating cells from blood by using a filter apparatus having first and second ports and a filter member therebetween having a changeable porosity. The filter member includes a stack of porous polymer sheets that preferably has a gradient of a physical or chemical characteristic in the direction of stacking. This can include a gradient in porosity, hydrophilicity or zeta potential. In a first step, blood is filtered through the apparatus when the filter member is set to a compressive state having a first porosity capable of capturing the objective cells. In a later step, the filter member is then set to a non-compressive state having a second porosity, higher than the first, for recovering the objective cells. The change in porosity results from the enlargement or reduction of the diameter of the pores of the filter member. The method can also include washing the filter member when the member is set to a porosity that is higher than the first porosity but lower than the second porosity.

Abstract: The present invention relates to flow control devices (4) for use with cartridge filter cleaning systems. The flow control device (4) includes a cylindrical portion (8) which extends away from a conical portion (6). When the device (4) is used with a nozzle (9) attached to a blow tube (13) the device (4) will uniformly clean a dirty cartridge filter (5). The advantage of the invention is that the device (4) can be used in the current range of air flow rates and nozzle sizes that are used in the cartridge cleaning industry. Whereas the prior art systems (7) show deficient performance when used across the full range of air flow rates currently applicable in industry.

Abstract: The invention relates to new regenerable filtration adjuvants which are usable for the filtration of liquids, particularly beer at the end of the secondary fermentation storage, characterized in that they comprise synthetic or natural incompressible polymer grains or natural incompressible grains grains having a sphericity coefficient varying between approximately 0.6 and 0.9. The invention also relates to a method for regenerating a filtration adjuvant.

Abstract: The process for flushing filtration modules of a cross flow filtration device is carried out in a unit that is used for the clarification of liquids in a retentate circulation circuit. When the unit is shut down, for example as the result of a power failure, filtration modules are flushed free of solid particles by the supply of an addition of flushing agent that increases over time and/or geometrically into the retentate side of the cross flow filtration device. As a result, the danger of clogging of the filtration modules is largely avoided.

Abstract: A filtration tank (1) for purification of polluted water includes a chamber (12). Upper and lower filtration screens (20, 22) are supported within the chamber. Filtration particles (18) are confined between the upper and lower screens. Polluted water enters the chamber through an inlet (26), passes through the screens and the filtration particles and exits the chamber through a purified water outlet (28). Periodically, the inlet and outlet are closed and the water in the chamber is drained through a drain outlet (32). Nozzles (42, 45) spray cleaning fluid over the filter particles and screens to dislodge trapped dirt.

Abstract: A method and apparatus for washing a filter fabric (3) of a filter press. The method includes filtering a material to be filtered containing a liquid and solids through the filter fabric (3) in a filter cell (20), retaining the solids on a surface of the filter fabric (3) thereby forming a filter cake (18) on the filter fabric (3), discharging the filter cake (18) from above the filter fabric (3) to one side of the filter press only, conveying an area of the filter fabric (3) soiled during the previous filtration step to a washing cell (21) for washing the soiled area of the filter fabric (3) and washing the soiled area of the filter fabric (3) in washing cell (21).

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 filter for removing particles from a feed liquid. The filter includes a filtration material having a metal oxide composition selected to provide the material with an affinity for the particles of the feed liquid. The affinity of the material is dependent upon a pH of the feed liquid.

Abstract: A permanent fluid filtering system includes a cylindrical body having an upper end, to which an inlet tube is connected, and a lower end, to which an outlet tube is connected, and a latitude thread filter assembly disposed within the cylindrical body. The latitude thread assembly is compressible and expandable in accordance with a fluid flowing direction, thereby varying a porous structure of the filter assembly. The permanent fluid filtering system further includes a fluid flow stabilizing plate for stabilizing the flow of dirty fluid fed inside the body through the inlet tube.

Abstract: Fines, that are present in lubricating oil, and their organo-metallic coatings are contacted with aqueous solutions of strong acids to solve the problems of plugged cartridge type filters. The present process employs a washing step whereby, following a filter cycle that is terminated due to a pressure build-up, a hot aqueous solution of a strong acid with a pH of approximately 1.5, is circulated through the plugged filter cartridges until the fines and organo-metallic coatings are solubilized. The acid wash solution is kept separate from the filter feedstock and filtrate by suitable valving, piping and tankage so as not to contaminate it. The filter cartridges may be rinsed prior to reintroduction of the feed stock to begin the next filter cycle.

Abstract: A filtering apparatus comprises: a pressure vessel; a plurality of filter elements arranged within the pressure vessel, the filter elements each having an upper end, a lower end and a side wall; filling bodies positioned within the filter elements; a first conduit for introducing compressed gas into the pressure vessel; a second conduit for transporting unfiltered liquid to and from the pressure vessel; and a third conduit for removing filtrate from the pressure vessel and transporting back-flushing liquid to and from the filter elements, the third conduit positioned proximate to a bottom portion of the pressure vessel and attached to the lower ends of the filter elements, such that the third conduit provides a support structure for the filter elements and the back-flushing liquid introduced via the third conduit fills the filter elements in a direction from the lower ends toward the upper ends, the volume of back-flushing liquid introduced into the filter elements limited by the filling bodies.

Abstract: A method and an apparatus for cleaning filters contaminated by hot-melting resins and polymers in situ, without removing the filtering elements. The method comprises a preliminary step, during which the circulation of the product to be filtered through the filter to be cleaned is interrupted, and a draining step, during which a pressurized draining fluid is passed through the filter in order to empty the filter of the residual product. A filter cleaning step is then performed during which a cleaning fluid, constituted at least partially by superheated steam, is passed through the filter. The fluids used to clean the filter are then subjected to treatments to eliminate pollutants.

Abstract: Oil and oil additives separated from a contaminated solid particulate filter medium, preferably diatomaceous earth particles. Portions of a mixture of oil, oil additives and the filter medium are compressed into pellets that are extracted with liquid or supercritical CO.sub.2 to form a liquid solution. The solution is separated from the pellets and then heated to 20.degree.-60.degree. C. at a superatmospheric pressure to drive off CO.sub.2 gas, which is preferably recycled by compression into liquid or supercritical CO.sub.2.

Abstract: A method and apparatus to clean a filter drum used for thickening lime mud. The drum is rotated about a horizontal axis in a first direction so that the circumferential surface of the drum moves into contact with lime mud in a vat and a precoat layer formed on the drum, as well as an external layer of lime mud which forms a thickened lime mud cake when a vacuum is applied to the drum withdrawing liquid from the lime mud. The thickened external layer of lime mud cake is scraped from the drum at a second side of the vat, and at a first opposite side of the vat a first jet of liquid is directed onto the drum surface (e.g. at a pressure of about 30-100 bar) to remove a strip of the precoat layer, a third jet of liquid cleans the drum after removal of the precoat layer, and a second jet of liquid is directed onto the drum with sufficient intensity (e.g. a pressure of about 2-20 bar) to remove, by spreading and partially detaching, a strip from the thickened lime mud cake.

Abstract: Centrifugal filtration capable of improving recovery of crystal in a baskey. The basket is so arranged that a central axis thereof is inclined with respect to a horizontal direction to obliqely downwardly orientate a bottom wall of the basket. A crystal recovery auction pipe is arranged which includes a pivotally movable section pivotally moved in the basket, of which a distal end is advanced into crystal in the basket. Crystal in the basket is recovered by suction through the distal end of the suction pipe, which is ultimately displaced to a corner of the basket between a lowermost portion of a peripheral wall of the basket and a bottom wall thereof. This permits crystal collected to a lowermost section of the basket to be substantially recovered by suction through the suction pipe, to thereby improve crystal recovery.

Abstract: A process of dissolving solid waste material in packed beds comprises the addition to the packed bed of a solvent for the solid waste and a material which releases a gas on contact with the solvent which forms channels in the packed bed allowing more rapid access of the solvent to the bed.

Abstract: A method and apparatus for filtering particulates from a turbid liquid is provided. The apparatus is preferably used to filter particulates from water used to flush a pipeline after a cleaning operation, after hydrostatic testing or during product displacement at a high flow rate. The apparatus includes an inlet valve for receiving the turbid liquid from a liquid source connected to a gas buster for discharging the turbid liquid and air into a break tank located beneath the gas buster. A self-cleaning portable liquid filter having an inlet is connected to an outlet of the break tank and includes a screen filter for receiving the turbid liquid from the break tank. Particulates from the turbid water are accumulated on an internal surface of the screen filter and clean water is discharged from the filter through a discharge port. A flush mechanism is provided to rinse the accumulated particulate cake from the surface of the screen filter upon actuation of an automatic rinse cycle.

Abstract: A backwash sealing shoe is provided for a filtration system including a tank having an undivided filtration bed and a plurality of side-by-side headers within the bed, each header in communication with a respective port in a wall of the tank. The sealing shoe includes a hydraulic section including an opening surrounded by a seal and adapted to sealingly engage the wall in surrounding relationship to at least one of the ports; and at least one blocking section adjacent the hydraulic section on one side thereof and including a plate surrounded by a seal and adapted to sealingly engage the wall in surrounding relationship to at least one adjacent port to thereby block flow from the tank through at least one adjacent port during a backwash operation.

Abstract: The present invention generally relates to a method for reducing the content of organic solvent in an aqueous dispersion of a cellulose-reactive hydrophobing agent, prepared by emulsifying a molten cellulose-reactive hydrophobing agent containing organic solvent in an aqueous solution containing one or more emulsifying agents. The method comprises contacting the aqueous dispersion under agitation with a sorbent, said sorbent having the capacity of absorbing or adsorbing organic molecules, or a gas, whereby the solvent is transferred to the sorbent or the gas.

Abstract: In a method for backwashing a water processing system using a buoyant filter layer constrained under wire mesh screen extending across a processing vessel, a water surface level in the processing vessel is lowered below the wire mesh screen. Air is subsequently released from under the buoyant filter layer to separate substances clogging the filter layer, while allowing the release of air out of said vessel from an upper part thereof. By lowering the water surface level below the upper wire mesh screen, the filter material is allowed to move more freely because the filter material is not restricted by the wire mesh screen from making upward movement. Hence, when air is released from under the filter layer, the filter material can move uniformly over the entire filter layer, and the clogging substances such as SS captured by the filter material and the biological film formed on the surface of the filter material can be favorably removed without damaging the filter material.

Abstract: A filter includes a cylindrical filter element having a longitudinal axis, first and second end surfaces, and a plurality of longitudinal pleats. Each of the pleats has a pair of legs with first and second surfaces. The pleats are in a laid-over state in which the first surface of each leg is in intimate contact with the first surface of an adjoining leg and the second surface of each leg is in intimate contact with the second surface of an adjoining leg over substantially the entire height of each leg and over a continuous region extending for at least approximately 50% of the axial length of the filter element. An impervious end cap is connected to the first end surface of the filter element.

Abstract: A filtration apparatus and method having a housing, a filter element, an inlet, a first discharge outlet and a second discharge outlet. The housing includes a bottom and an upwardly extending surrounding wall. The filter element is disposed in the housing and spans the surrounding wall with the filter element spaced above the bottom of the housing to define an upper chamber and a lower chamber, and the filter element being angled, preferably 45 degrees from the horizontal, so that one end of the filter element is lower relative to the other end. The inlet is in fluid communication with the upper chamber for receiving waste water containing particulate contaminants. A first discharge outlet is in fluid communication with the lower chamber for discharging filtered waste water. The second discharge outlet is in fluid communication with the upper chamber adjacent the lower end of the filter element for discharging filtered particulate contaminants.

Abstract: A method and apparatus for wetting, flushing and performing integrity checks on encapsulated PTFE filters includes an integral filter housing (112) encapsulating a PTFE filter (114) therein. The filter housing has an inlet pipe (116), a filter outlet pipe (118), and a vent pipe (122). First controllable inlet valve (126) is coupled to the inlet pipe of the filter housing for supplying a solvent solution to pre-wet the encapsulated PTFE filter. A second controllable inlet valve (117) is also coupled to the inlet pipe of the filter housing for supplying gas from a source under pressure to check the integrity of the pre-wetted PTFE filter. A third controllable inlet valve (119) is also coupled to the inlet pipe of the filter housing for supplying a source of water to flush the pre-wetted filter after checking its integrity.

Abstract: In order to clean a deposit filter having filter elements (4) installed in a suspended manner, first, with the plenum (3) filled with flushing medium, the liquid is discharged completely or partially from the filter chamber by way of an emptying line (7) by opening a ventilating line (6) arranged in the uppermost region of the filter chamber (2), then, by means of a pressure-generating line (8) which is arranged on the plenum and by way of which propellent gas or flushing medium under pressure is conveyed into the plenum, a pressure surge is generated in the plenum and drives the flushing medium through the filter elements, and finally the impurities, together with the liquid, are discharged. Before the pressure surge is exerted, an underpressure can be generated in the filter chamber, in order further to increase the effect. If desired, the filter elements (4) can have an upper gas-impermeable region (5).

Abstract: A method of cleaning polymer residue from a polymer melt filter formed of a sintered powdered metal includes pyrolyzing the polymer residue-contaminated filter within a heated chamber at a temperature within the range from about 400.degree. to about 600.degree. C. and for a time sufficient to pyrolyze substantially all of the polymer residue. Simultaneously with such treatment, the heated chamber is flushed with steam to prevent combustion of the polymer residue. The pyrolyzed filter is then treated with a solvent and back-flushed with a pressurized fluid stream by passing the fluid steam through the filter in a direction opposite to the polymer melt flow therethrough.

Abstract: A method and apparatus for fibrous suspensions in the wood processing industry and more specifically to a so-called drum cylinder, the basic construction of which comprises a vessel, into which suspension being thickened is supplied and a wire-surface cylinder rotating in the vessel. The drum filter is characterized in that the closure member of the drum filter has a channel for leading gas from the filtrate tubes through the compartments of the distribution chamber to the outside of the closing member. The method is characterized in that the operation phase of the filter cylinder is divided into five separate stages. In the first stage, when the cylinder descends on to the vessel, air and the initial filtrate are discharged from the filtrate components and the formation of the pulp web on the wire surface begins. In the second stage, filtrate is discharged with vacuum and the formation of the pulp web continues.