Abstract: The method of treating sewer scum including combustibles and debris includes the steps of collecting the scum from sewage, delivering it to a perforated filter drum, continuously rotating the drum upon an inclined longitudinal axis, applying heated air under pressure to the exterior of the drum along its length inwardly of the perforations, discharging the debris continuously and collecting the filtered combustibles. Apparatus for filtering said scum includes an elongated cylindrical perforated drum rotatable on an inclined axis receiving scum at its upper end and discharging debris at its lower end. A cylindrical shell sealingly encloses the perforated portion of the drum for providing a pressure chamber above the drum and a collection chamber below the drum. An elongated air channel along the interior of the shell delivers high pressure heated air to said pressure chamber and filtered scum accumulates in the collection chamber.

Abstract: An apparatus for separating suspended solids from a liquid includes a tank, a floating bed of granular filter material held at the upper portion of the tank at the time of filtration, a feed pipe for feeding the liquid at a position between a filtering section and a sedimenting section, a hollow member or members which are arranged within the tank at a position below the position of the filter bed but above the position of the feed pipe, an air supply pipe which blows air up through the hollow member or members, thereby creating a turbulence required for effective backwashing, an arrangement for bringing the filter bed down to a position where the lowermost surface of the filter bed is held below a position substantially flush with the top end of the hollow member or members, a means for discharging a filtrate from the tank which is arranged in the top portion thereof, and a means for discharging a deposit of the suspended solids from the tank, which is equipped at the bottom portion thereof.

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

Abstract: A filter for purifying a fluid containing ferromagnetic particles, e.g. water in the primary circuit of a nuclear reactor using pressurized water, comprises a cylindrical envelope containing steel beads and provided with a coil for magnetizing the beads. The beads are supported in a cylindrical basket located in the cylindrical envelope and the side wall of which is perforated in certain zones. Deflectors are arranged within the basket radially opposite the perforated zones of the basket side wall. Fluid to be purified enters through a central drip tube which is provided with radial perforations in zones radially opposite the deflectors which serve to prevent fluid passing through the beads in a solely radial direction.

Abstract: A horizontal vacuum belt filter having an endless filter cloth on which a residue filter cake is, in use, formed; a filter head roller; a rotatable discharge roller located some distance forward of the head roller, a portion of the filter cloth passing over a segment of the cylindrical surface of the discharge roller and being in engagement therewith; a plurality of longitudinally directed and circumferentially spaced apart passages being provided in the discharge roller which are each in communication with a different segment of the cylindrical surface of the discharge roller via suitable bores; a first valve for directing a discharge liquid to those passages which are in communication, at any particular time, with that segment of the cylindrical surface of the discharge roller engaged by the filter cloth; and a plurality of second valves for permitting flow of discharge liquid only from those passages that are in communication with the said segment through the bores associated with those passages to the sai

Abstract: Apparatus for separating and removing, exclusively by mechanical means, a polluting liquid or slimes floating on water or another liquid not miscible with the polluting substance and comprising:a flexible floating platform of a specific gravity less than that of the water, at the center of which is mounted a suction device provided with at least a lower suction pipe the platform having a plurality of channels with entrance orifices arranged on the periphery thereof and provided with a weir sill, the or each suction pipe being connected, through a flexible pipe, to a pumping unit mounted on a remote fixed or floating supporting means.

Abstract: A filtering method, and a filter, for removing turbidity and color from water, uses as a filtering medium, a blanket of non-woven fabric, particularly a blanket of felted fibers. The blanket is, in use, supported on a gravel bed, slotted ceramic blocks or the like, and can be held and protected by a grating.

Abstract: A filter apparatus comprising a number of filter trays arranged in layers to form a stack. Each filter tray is of a glass fibre reinforced plastics material and comprises a central web having upstanding and depending parallel ribs extending between one end of the filter tray to the other end thereof so as to define a number of parallel channels. A micro filtration or ultra filtration membrane is interposed between adjacent filter trays, and alternate ends of the channels are closed so that liquid flowing along a channel in one filter tray flows through the membrane and leaves the stack through the open end of the channel in the adjacent filter tray.The filter trays are located in a plastic tube held within a demountable pressure casing having a header plate to divide the casing into two chambers each connected to a respective end of the filter trays.

Abstract: A hollow filter housing is provided with a support and a plurality of fiber bundles located on the support. The fibers extend within the filter housing in direction between an inlet and an outlet of the housing. The contaminated medium is introduced into the housing through the inlet in a direction towards the outlet to flow past the plurality of the fiber bundles. The contaminated medium becomes filtered as it passes through the filter bundles without compressing the latter against the support.

Abstract: A process and apparatus for the treatment of the aqueous backwash effluent resulting from a backwashing operation of an industrial filter. During the backwashing operation, particulate matter and solids are dislodged from the industrial filter so as to be entrained in the backwash effluent, and the effluent is passed through a backwash filter to remove these materials. After passing through the backwash filter, the normally water-based backwash solution is directed to a holding tank for storage until a subsequent backwashing operation is required. The pH value and chlorination level of the backwash solution are periodically adjusted to maintain them within selected ranges in order to optimize the sanitizing effect of the solution during the backwashing operation. The process and apparatus results in the consumption of a much smaller quantity of water than prior arrangements wherein a singleuse backwash solution is dumped into the general effluent discharge of the plant.

Abstract: In cleaning plate-type filter elements in a tank filter, the tank is opened and a cleaning tube is placed upwardly around one of the downwardly extending filter elements providing an annular flow space along the length of the element. A seal member is located in the upper end of the cleaning tube to close off the upper end of the annular flow space. Pressurized cleaning fluid is supplied into the lower end of the tube where it flows upwardly through the annular space and then into the filter element to dislodge any contamination. The material displaced continues its flow through the filter element in the same direction as is taken by the fluid being filtered.

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

Abstract: An apparatus for filter backwashing includes a vessel containing a bed of filter media. Laterals with nozzles are disposed below the filter media to convey backwashing air and water into the filter bed. Below the laterals are located a manifold and a distribution plenum to carry air into the laterals. The manifold and the distribution plenum are separated by a common wall having a plurality of ports to provide communication therebetween. Communication between the distribution plenum and the laterals is provided by a plurality of conduits, one conduit extending into each lateral from the distribution plenum.

Abstract: Method and apparatus of concentrating solids from a suspension by feeding material in a liquid medium to a first zone that includes a vertically oriented foraminous filter basket supported by circular bands which are connected to an open frame basket supporting cage. Rotary impeller arms significantly spaced from the basket inclined from the vertical and located about midway of the lower half of the basket impart a circular laminar movement to the material. A vertical cylindrical tank surrounds the basket. Filtrate is collected in the annular region between the basket and tank. Discharge outlets with rate of discharge controls extend outwardly and downwardly from the bottom of the separator apparatus. Operation can be batch or continuous with level of filtrate in the tank being maintained on a par with the level of the feed in the basket.

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

Abstract: A filtering apparatus has a housing and a brush-like filter element in the housing. The filter element includes a support which is permeable to the liquid or gas to be filtered. A filtering medium is secured to the permeable support and is in the form of strands which may be formed from flexible natural fibers, synthetic resin fibers, glass fibers, graphite fibers or metal fibers. The strands are so arranged that they are pressed against the permeable support during a filtering operation. This causes the strands to form a mat on the permeable support. The liquid or gas must pass through the mat and is thereby filtered. A filtering method using the apparatus involves passing a liquid or gas through the filter element so that a mat for filtering the liquid or gas is formed by the strands, and the liquid or gas is purified after leaving the filter element.

Abstract: There is provided a composite strainer unit suitable for use with particulate substances in a liquid environment comprising a first strainer unit in combination with a second strainer unit. The first strainer unit having a much larger effective area than the second unit whereby, at any given speed the working liquid will pass through the first strainer unit at low velocity and through the second strainer unit at high velocity. The composite unit is provided with a valve means whereby flow access to the first strainer unit may be closed to permit high velocity flow through the second unit only.

Abstract: A back-washable filtering element, especially for use with pumps, and more particularly for use with pumps that handle liquids with solid material entrained therein, consists of a helical coil spring disposed in a flow path for the liquid to be filtered. A movable element in the flow path is mechanically connected to the spring and compresses it axially under the effect of the back washing liquid to automatically reduce the flow capacity. The resultant "shrugging" of the spring also permits it to clear itself of filtered material to facilitate the back-washing.

Abstract: The self-cleaning filter for purifying a liquid from suspended particles has a housing with pipes for the inlet of the liquid to be purified and for the outlet of the clarified liquid, accomodating at least one filtering partition dividing the internal space of the housing into chambers for the liquid to be purified and for the clarified liquid, and means for flushing this partition with a countercurrent of the clarified liquid. The inlet pipe for the liquid to be purified is arranged on the housing within the chamber for the clarified liquid so that its geometric axis is substantially parallel with the plane of the filtering partition and communicates with another pipe received in the chamber for the clarified liquid so that its geometric axis extends centrally of this chamber, substantially perpendicular to the plane of the filtering partition, the latter having made therein an opening the edges whereof are connected to said another pipe.

Abstract: The invention pertains to an engine installation using marine water as a coolant and having an intake conduit system for drawing marine water to the engine including a strainer at the inlet and a filter between the strainer and the water pump. To clean the filter and strainer which periodically becomes clogged with foreign matter while the engine is operating, a valve mechanism is provided between the filter and the water pump which is operative to close the conduit to the pump and to admit compressed air to the filter side of the valve mechanism for a short time to blow back the clogging material from the filter and strainer to the sea. In a semi-automatic embodiment the valve mechanism is a solenoid operated 3-way valve which is preferably operated from the pilot house for a short interval of about 10 seconds when the boat operator observes an above normal engine temperature.

Abstract: An automated entrainment abundance sampler for the collection of ichthyoplankton specimens and its operation is disclosed. An inverted conical screen or net is utilized to collect specimens from water supplied by a suitable pump. After a set time period, the collected specimens are further concentrated in a secondary concentrator and transferred to a sample container. The conical screen is rinsed to insure that all the specimens are transferred to the secondary collector which is, in turn, rinsed to further insure that all the specimens are carried to the sample container. A suitable control system is provided to allow the sampler system to operate automaticaly in the collection of specimens over a preselected period of time.

Abstract: Process and apparatus for separating particulate material from fluids. Essentially, the process and apparatus involves passing a dispersion of particulate material in a fluid through a porous, solid tubular member, which can retain the particulate material within the tubular member but permits passage of the fluid therethrough. The process and apparatus disclosed are especially useful in washing and/or adjusting the concentration of particulate materials dispersed in fluids by recycling the dispersion through the porous member until the concentration of dispersed particulate material is increased to a predetermined degree.

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

Abstract: Method of and apparatus for separation of solids from a liquid employs an elastic sheet filter which has pores of diameter larger than an average diameter of the solid and smaller than the maximum diameter thereof. The liquid is filtered under pressure by a filtered residue layer developed on the sheet filter. Then liquid is rapidly introduced to the sheet filter portion from the reverse direction to liquid flow occured during the filtration of the liquid so that the sheet filter and filtered residue layer pressed during the filtration is rapidly pressed in the reverse direction, whereby the filtered residue layer is flaked out in the liquid and separated therefrom.

Abstract: A filter has a housing defining a closed chamber around a hollow shaft which is rotatable in the housing and which carries a plurality of filter elements so that fluid can be pumped through the filter elements into the hollow interior of the shaft. The shaft is rotatable with the filter elements relative to the housing for cleaning filter cake off the filter elements between filtering operations. An annular and hollow bellows-type seal surrounds the shaft and has one axial end secured to the housing and an opposite axial end engageable with the shaft for sealing the shaft relative to the housing. This bellows-type seal is made of thin and flexible stainless steel. The inside of the seal may be pressurized by a liquid or gas to force the end of the seal against the shaft and form a tight connection therebetween.

Abstract: A filter for polymer melts and solutions comprises a casing having an inlet opening and an outlet opening. The casing accommodates a hollow mandrel supporting filter elements which are axially unmovable due to the provision of clamping flanges. Each element consists of a spacer plate located between filtering baffles, a sleeve having through radial passages communicating the inner space of the filter element with the inner space of the mandrel, the sleeve being mounted between the filtering baffles on the periphery of the mandrel, and a seal located between the filtering baffles on the periphery of the spacer plate. In addition, the casing accommodates auxiliary seals provided between the filter elements on the periphery of the mandrel and a spacer device arranged between the filter elements. The spacer device comprises auxiliary spacer plates each corresponding to the filtering surface of the filtering baffle. The filter is also provided with a washing device.

Abstract: Process for dewatering thickened sludge comprising the steps of depositing thickened sludge onto a porous support, partially dewatering the thickened sludge by establishing a vacuum within said porous support, compressing the partially dewatered sludge on said porous support at a pressure of from 1 to 10 kp/cm.sup.2 to further dewater the sludge and to form a sludge cake, compressing the sludge cake on the porous support at a pressure of from 10 to 300 kp/cm.sup.2 to further dewater the sludge cake and discharging the dewatered sludge cake from the porous support.

Abstract: A method of and an apparatus for regenerating a pressure filter in which the liquid to be filtered is flown through a filter medium arranged in such a way as to partition the interior of the filter housing into a pressure chamber adapted to receive the liquid to be filtered and into a filtrate receiving chamber from which the filtrate is discharged, wherein, for the purpose of regenerating the filter, the introduction of liquid is interrupted, this step being accompanied by the introduction of a pressurized gas into the pressure chamber of the filter in order substantially completely to remove from the filter both the liquid not yet filtered and the filtrate still present, and wherein, upon completion of the emptying step, the introduction of pressurized gas into the pressure chamber of the filter is interrupted and the filter medium on its side facing the pressure chamber is washed by means of a washing medium, this step being accompanied by the introduction of a pressurized gas into the filtrate receiving c

Abstract: Slurry to be densified by removal of water is passed into an inlet of a housing, through the housing, and out an outlet. Inside the housing are a plurality of elongated hollow filter elements, which extend in the direction of flow of the slurry. Water in the slurry passes through the walls of and into the interiors of the hollow filter elements, as the slurry flows along the lengths of the filter elements. The cross-sectional area of the flow space for the slurry, defined between the exterior surfaces of the filter elements and the interior wall of the housing, decreases as one proceeds along the lengths of the filter elements. As a result, the flow speed of the slurry does not decrease proceeding in the flow direction, but instead is maintained at least substantially constant, or is even caused to increase (accelerating flow).

Abstract: A self-cleaning filter for cleaning liquids from suspended matter comprises a container with filtering partitions which divide said container into parallel sections for the contaminated liquid and into a cleaned-liquid section located between the first two sections. Each contaminated-liquid section is provided with a device for backwashing the filtering partition, said device being installed with a provision for moving over the filtering partition, being pressed flexibly against it and comprising a hollow body which is open at the side of the filtering partition and communicates with the atmosphere. Arranged around the entire perimeter of the body at its open side is a circular recess with through holes in its bottom. In this recess is installed a mating plate capable of reciprocating therein so that there is a clearance between its face and the bottom of the recess, said clearance forming a chamber which communicates with the contaminated-liquid section through said holes.

Abstract: A filter barrier or ring fixed to the bottom of a washing machine basket includes a plurality of closely spaced flexible teeth in a circumferential row extending outwardly and downwardly to divide the tub into first and second zones for filtering laundry liquid during a washing cycle. The teeth deflect in response to centrifugal spinning forces to effect self-cleaning.

Abstract: In a filtration apparatus of the type wherein the material to be filtered is fed to an inner compartment between a filter element, supported by a hollow perforated cylindrical body, and a concentric flexible bladder, the bladder being capable of being pressed by a hydraulic fluid against the material to be filtered thus forcing the liquid component through the filter, the inlet to the inner compartment for liquid/solid mixtures comprises a substantially cylindrical chamber provided with circumferentially-spaced apertures adapted to connect with the inner compartment, said chamber being located at one end of the cylindrical body, an inlet line or lines into said chamber and a hollow cylindrical member movably constructed and arranged to cover or expose said apertures.

Abstract: A control unit is formed of a housing containing a filter with an inlet and outlet in line above the filter, the latter forming a channel with the housing; a pressure reducer is positioned between the inlet and the outlet above the filter. A rotary valve positioned between the filter and the pressure reducer reverses the flow in the unit. A plug-valve is located in the housing to provide drainage and the plug-valve is connected to the rotary valve so that on reversal of flow, the plug-valve opens to drain the unit.

Abstract: The specification discloses an improvement in rotary drum screens for the filtration of liquids which comprise (a) a drum having a central horizontal axis and a radially outer surface, (b) a plurality of microscreen grids mounted on the radially outer surface of the drum, each of the microscreen grids comprising a screen which is divided into a large number of small cells by walls which extend radially with respect to the drum, (c) means for introducing the liquid to be filtered into the interior of the drum, (d) means for rotating the drum about its central axis, (e) a backwash header mounted outside the radially outer surface of the drum, and (f) a backwash receiving trough mounted within the drum for collecting filtrate accumulated on the screen. The liquid to be filtered is introduced into the drum at one end thereof, and the drum is supported so that it is partially submerged in the filtered liquid.

Abstract: A method and system for use with rotary vacuum filters having a plurality of circumferentially spaced filter segments, for selectively applying blower air to the filter segments at predetermined rotational positions at which relatively unrestricted openings to the valve ports are provided to thereby blow the filter segments, and for bypassing the stream of blower air to the atmosphere when the filter segments are not blown. The apparatus for practicing the invention may also include a blow-back trap for trapping excessive amounts of residual blow-back filtrate during blowing of the filter segments.

Abstract: An improved sewage treatment system including a horizontally elongated tank divided transversely into a primary, aeration compartment, a secondary, settling compartment and a tertiary, filtering compartment. In a first aspect of the invention, overflow of treated effluent from the tank enters a further treatment section, which may constitute a longitudinal extension of the tank, wherein the effluent is constrained by baffles to flow in an elongated path while having chlorine or ozone mixed therewith to provide further purification. Another aspect of the invention resides in the novel structure of the filtering section wherein filter screens of different guage or opening size are used to achieve a greater degree of purification.

Abstract: An apparatus provides for continuous filtration of a mother liquor and continuous removal of solids from the filter element so that the apparatus need not be shut down for cleaning or replacement of the filter element. The solids are separated from the mother liquor as a concentrated suspension and the apparatus can be replicated in stages using successively finer filters so that a filtrate free of particles above any specified particle size can be obtained.

Abstract: A lint filter for an automatic washing machine having a rotatable walled basket for receiving items to be washed and means for recirculating liquid therein. The lint filter comprises an annulus channel member having an inside wall, an outside wall, and perforations for liquid to pass therethrough. The annulus channel member is secured to the wall of the basket inwardly thereof. There is provided a plurality of elongated protuberances attached to the inside wall of the annulus channel member with their bases positioned toward the rotational axis of the basket such that during rotation of the basket lint will be removed from the protuberances by centrifugal force.

Abstract: A filter comprising a vessel in the form of a closed drum which is rotatably mounted about a horizontal central axis, and a plurality of longitudinal, hollow, horizontal filter elements which are arranged in a ring. The filter elements extend between and are connected to the end walls of the drum for rotation about the central axis together with the drum. The peripheral surfaces of the filter elements constitute a filter surface which, upon rotation of the drum and the elements, will submerge into and emerge from the liquid to be filtered which is contained in the drum. At one end the filter elements extend through the end wall of the drum, and this end of the filter elements is open to permit unobstructed discharge of the filtrate. A blow tube with nozzle means is provided within each filter element, with the blow tube serving to remove solids deposited on the filter surface when the surface is above the liquid level in the vessel.

Abstract: The present invention relates to a double leaf filter head for drawing clear samples from a liquid to be analysed. The filter head is of especial use in drawing samples of phoshoric acid whose SO.sub.4 .sup.-.sup.- ion content is to be analysed by turbidimetric methods.

Abstract: A separator for solid particles from a liquid, such as a dirty industrial machine tool coolant, comprising a settling tank with one or more frames or assemblies of horizontally extending tubular filters and means to removably clamp such frames against a side of the settling tank over suction outlets. Each of the filter frames comprises a chamber into which all of the tubular filters communicate, which chamber is provided with a gasket that is pressed against the vertical wall of the settling tank around an outlet therefrom. Socks may be provided for the tubular filters, which socks may contain seams that are aligned in vertical planes for the easy severance of the cakes of solid particles which build up upon them. A bottom drag out conveyor may be provided for the settling tank and a suction pump draws the liquid through the filters into an adjacent clean tank.