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 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 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 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 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.

The present invention relates to a filter arrangement (1) comprising: a chamber (12) comprising 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 (2) having a longitudinal extension arranged inside of said chamber (12), wherein said filter element (2) comprises a semi-permeable filtration wall (22) comprising a folded filter (24) arranged in a zig-zag configuration between an inner perforated cylinder (26) and an outer perforated cylinder (28) and an internally located back- washing arrangement (3). The back-washing arrangement (3) comprises: an elongated and hollow body (32) having a longitudinal extension, which is substantially parallel to the longitudinal extension of the filter element (2), a mechanism configured to drive said body (32) in a rotational and/or an axial movement, a plurality of nozzles (34) arranged in fluid communication with a cavity inside of said body (32), said plurality of nozzles (34) projecting laterally from said body (32) such that a distal end (36) of each of said plurality of nozzles (34) is arranged in close proximity to said inner perforated cylinder (26) and an outlet (320) arranged in fluid communication with said cavity of said elongated and hollow body and wherein said plurality of nozzles (34) are arranged parallel to each other along a straight line on said body (32) such that they all project in the same direction.

Apparatus for filter cleaning including a filter element surface (12) to be cleaned, and a cleaning head (10), characterized by a controller (16) operative to move the cleaning head (10) with respect to the filter element surface (12) in a spiral scanning trajectory in such a way that a relative path of the cleaning head (10) with respect to the filter element surface (12) results in a trajectory that fully, or partially covers the filter element surface (12) and is produced by moving the filter element surface (12) in any combination of the following motions: a) one or more circular or semi-circular motions, b) one or more linear motions; while moving the cleaning head (10) in any combination of the following motions: c) one or more circular or semi-circular motions, d) one or more linear motions.

Provided is a fluid filtration unit including a housing accommodating a stationary cylindrical filter element, defining a raw fluid chamber extending between an inlet of the housing and raw fluid face of the cylindrical filter element, and a filtered fluid chamber extending between a filtered fluid face of the filter element and an outlet from the housing. A flushing and backspraying assembly includes at least one flushing pipe coupled to a lower pressure source and extending within the raw fluid chamber, and configured with a plurality of flushing nozzles disposed in close proximity with the raw fluid face of the filter element, and at least one backspraying arm coupled to a pressurized fluid source and extending within the filtered fluid chamber and configured with an array of backspraying nozzles disposed in close proximity with the filtered fluid face of the filter element, and a driving mechanism for selectively imparting the flushing and backspraying assembly with rotary and linear motion.

A self-cleaning mechanism for a filtration system, being disclosed, comprising a filter element positioned in a filtration chamber and a suction scanner for cleaning the filter element upon activation of a cleaning session, wherein a linear motion of the suction scanner between an initial position and a final position is automatically regulated by a linear displacement regulator comprising (i) a regulative-fluid compartment in liquid communication with a regulative flow-restrictor; and (ii) a regulative-fluid compression element linearly comoving with the suction scanner for enforcing a regulative-fluid filled in the regulative-fluid compartment, to flow through the regulative flow-restrictor. Further being disclosed are a filtration system comprising said self-cleaning mechanism, and a method for regulating the linear displacement of a suction scanner of a self-cleaning filtration system by said linear displacement regulator.

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.