continuous filtration rotary backflush Patt filtration CONTINUOUS FILTRATION Continuous Filtration is not necessarily constant flow or constant pressure filtration. Of course, if planned shutdowns exist for other reasons such as color changes or housekeeping, and filtration media renewal is done during this time, then the production predictability goal becomes academic. For those processors who need to maintain predictable production, several solutions are offered. Each solution involves the concept of Continuous Filtration. In the industry, Continuous Filtration is achieved by changing screens without slowing or stopping the extrusion line to effect the change. One solution used to provide continuous filtration is a modified slide plate screen changer. The slide plates are hydraulically driven and are set up in a one way track. Three slide plates, or blocks, are in the track as the screen change begins: one active block, one heated standby block and one recently cleaned block.