BV Products range of PFA – Paper band/bed filter units are semi-automatic, simplified membrane filters. The principle is simple. The units consist of a stainless steel mesh conveyor which supports a continuous length of filter paper. Waste water from the finishing operation passes on to the filter paper. Eventually the section under the discharge hose “blinds” or clogs and a puddle forms on the paper. Once it reaches a pre-set depth a float rises and trips the servo motor which indexes a fresh section of paper into place. At the end of a working day the waste paper is simply cut of and disposed in a hard waste container. The PFA units come in a number of sizes and capacities.