A backflush filter for liquid media, having a filter housing, which is formed by means of at least one supporting cage, which has at least two groups of slot-type apertures, and at least one filtering means supported on the supporting cage, where-in the apertures of each group extend in parallel alignment with one another and are separated from one another by ribs, and having a backflushing device, which is arranged in the interior of the filter insert, is rotatable and has at least one slit, said backflushing device being designed for flushing of the filtering means via the slit and apertures. The direction of motion of the backflushing device can be reversed during the backflush cycle and a filter insert therefore, wherein the backflush filter and the filter insert include a filtering means having a pleated, preferably multi-ply, filter fabric or filter cloth with pleating folds, and the ribs fit by means of a rib front into respective pleating folds.

A system may include a catch tray coupled with a flow distributor. A mesh screen and carriage may be positioned within the catch tray. A drive bar may be coupled with the carriage and a pitman arm. A gear box may be coupled with a motor and the pitman arm. A process may include distributing contaminated fluid onto the mesh screen. A screen plane of the mesh screen may be at a screen angle that is oblique relative to the direction of the force of gravity. The screen plane is defined by a top surface of the mesh screen. The process may include moving the carriage in a reciprocating linear motion by rotating the pitman arm, and spraying a liquid onto the mesh screen. Liquid may flow through the mesh screen forming clarified liquid, and contaminate may move along the top of the mesh screen to a contaminate outlet.

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 filtering device for treating ballast water and more particularly, a multicage-type device for filtering ballast water to prevent back pressure, wherein the multicage-type device for filtering ballast water includes a back pressure prevention tank on a backwash line for backwashing and discharging foreign substances that are inside a filter of the device for filtering, so that backwash water and the foreign substances in the backwash line are preliminarily stored in the back pressure prevention tank thereby preventing an increase of back pressure and preventing an increase of the back pressure on the backwash line by always maintaining a level of water inside the back pressure prevention tank at lower than an inlet port that is connected to the backwash line.

A device for filtering treating ballast water by way of a filtering method, and more particularly, to a compact and operability-enhancing multicage-type device for filtering ballast water, which distributes a lower portion of the device for filtering a discharge portion for discharging foreign substances after backwashing a filter and a backwash line, among features that are concentrated at an upper portion of the device for filtering, and communicates discharge tubes of each filtering unit in a single line, by considering the unique installation environment of the device for filtering that is coupled to a ship, thereby simplifying structure, reducing space required for installing the device for filtering in the upper portion of the device for filtering, allowing efficient maintenance by integrating foreign substance discharge and back pressure maintenance of each of the filtering units.