A filter arrangement includes: a chamber including a chamber inlet for unfiltered liquid, a chamber outlet for filtered liquid and a wall arranged to keep the unfiltered liquid and the filtered liquid separated, a filter element having a longitudinal extension arranged inside of the chamber, wherein the filter element includes a semi-permeable filtration wall including a folded filter arranged in a zig-zag configuration between an inner perforated cylinder and an outer perforated cylinder and an internally located back-washing arrangement. The back-washing arrangement includes: an elongated and hollow body having a longitudinal extension, which is substantially parallel to the longitudinal extension of the filter element, a mechanism configured to drive the body in a rotational and/or an axial movement, a plurality of nozzles arranged in fluid communication with a cavity inside of the body, the plurality of nozzles projecting laterally from the body such that a distal end of each of the plurality of nozzles is arranged in close proximity to the inner perforated cylinder and an outlet arranged in fluid communication with the cavity of the elongated and hollow body and wherein the plurality of nozzles are arranged parallel to each other along a straight line on the body such that they all project in the same direction.

A washing pipe is mounted on a washing guide provided on an outer side of an outer cylinder screen of the screw press and includes a washing pipe body and washing nozzles provided in the washing pipe body and configured to discharge washing liquid flowing from an inside of the washing pipe body toward the outer cylinder screen. A washing pipe swing supporter is configured to support the washing guide to allow the washing pipe to swing between a discharge position and a separation position. The discharge position is a position where the washing pipe is mounted on the washing guide and the washing liquid is discharged from the washing nozzles toward the outer cylinder screen. The separation position is a position where the washing nozzles are farther away from the outer cylinder screen than in a state where the washing pipe is positioned at the discharge position.

A filter assembly and method of filtering wastewater from a washing machine. The filter has a framework for supporting a first filter stage and a second filter stage, a connection on a top of the filter assembly for connecting to a wastewater stream, a diffuser positioned to extend into the first filter stage and configured to rotate about a vertical axis of installation within the first filter stage, and a second filter stage below the first filter stage and configured to receive overflow from the first filter stage. The filter assembly does not include a motor or motorized parts and wherein the diffuser is rotatable by way of the force of the wastewater stream fed into the first filter stage to diffuse the wastewater stream and to spray the wastewater onto and through the filter media allowing the filter media to catch debris within the first filter stage.

A filter for filtering liquid, comprising: a cylindrical housing; and a multiplicity of discs positioned perpendicularly to a height of the cylindrical housing, each of the multiplicity of discs comprised of a first number of cassettes, wherein each cassette is shaped as a truncated sector having a wide end and a narrow end, the cassettes arranged such that a perimeter of the disc is formed by the wide end of the first number of cassettes, and wherein each of the first number of cassettes is connected to a housing at its wide end, and each cassette having an opening along the wide end, wherein during filtration, liquid being filtered flows over the multiplicity of discs towards the perimeter of the multiplicity of discs.

A control mechanism for self-cleaning filtration systems. One embodiment is a controller for a filtration system that comprises a suction scanner and a screening element having modifiable respective locations therebetween. The controller comprises an input terminal for receiving a relative location signal and additional a differential pressure input terminal. The controller monitors differential pressure and outputs an activation signal after the differential pressure has exceeded a threshold value. The controller outputs a termination signal based on the relative location signal. Another embodiment is a filtration system that comprises: a screening element located within a filtration chamber, and a suction scanner for self-cleaning thereof. A location tracker communicates to a switching mechanism during self-cleaning sessions a signal indicative of a location of the suction scanner with respect to the screening element. The switching mechanism automatically terminates self-cleaning sessions based on the signal.

A self-cleaning pool or spa filter system having a filter body housing a set of filter cartridges, each filter cartridge rotatably connected to a filter holder, a spray manifold having an inlet for receiving water from a pump and a plurality of sprayers, a shaft connected to the filter holder and a motor, which can rotate the shaft and thus the filter holder, causing the set of filter cartridges to rotate about the shaft, exposing lengthwise each filter cartridge to the sprayers; a sun gear attached to the first shaft; and a set of planet gears, each planet gear being concentrically associated with one filter cartridge and engaged by the sun gear, causing transfer of a rotational movement of the sun gear to each planet gear and to each filter cartridge, causing each filter cartridge to rotate, exposing the entire circumference of each filter cartridge to the plurality of sprayers.

A screening system for solid removal includes a housing and a screen positioned within the housing. A flow inlet is operatively connected to an interior chamber defined by the screen. A sump is downstream from the flow inlet for capturing solids that do not pass through the screen. A flow outlet is downstream from the screen in fluid communication with the flow inlet. A moveable cleaning assembly may be positioned either within a perimeter of the screen, around the perimeter of the screen or both. The moveable cleaning assembly is moveable with respect to the screen.

A household dishwasher includes a washing container for holding a dishwasher load, a sump arranged at a bottom of the washing container, a filter system provided at the sump, and a spray arm for applying washing liquor and/or fresh water to the dishwasher load. The spray arm includes an extension piece which is mounted on the sump for rotation about a first axis of rotation and includes a filter cleaning nozzle for cleaning the filter system with the aid of the washing liquor and/or fresh water, and a spray arm satellite which is mounted on the extension piece for rotation about a second axis of rotation.

Provided is a washing device that washes a filter of an extraction device with a fluid, the extraction device including an extraction tank for storing an extraction material, a lid body supported openably and closably at a lower portion of the extraction tank, and the filter which is provided on the lid body, and on which the extraction material is placed, the washing device including, a tube body which is disposed at a fixed position with respect to the extraction tank, and through which the fluid passes, and an ejection port provided on the tube body and injecting the fluid toward the filter when the lid body is in an open state.

A self-cleaning, automated apparatus with a filter for fluids includes a nozzle unit assembly that has two nozzle tubes, one inside of another. Each of the tubes has a respective pattern of one or more slots or holes. As the tubes rotate, one with respect to the other, part of the pattern of the one coincides at times with part of the pattern of the other, resulting in a jet of fluid directed toward a filter to remove debris from the filter. The filter is rotated so the jet can reach all parts to be cleaned. The respective patterns of the two nozzle tubes may be an approximation of a helix and/or an approximation of a line.