The logical further development of the KBF filter. In this case the filtering is performed not with paper but with a continuous fabric belt made of plastic. Basically the CBF filter works by the KBF principle, i.e. with no relative rotation between the filter belt, the filter wheels and the sludge drivers. In special cases filter paper can be used in addition either temporarily or permanently. This does not require any conversions to the machine.
A strong, continuous metal link belt is tensioned in a half shell form, around two co-rotating pulley wheels. The angle of contact at the pulleys is approx. 180°. The link belt is driven by a geared motor acting via a drive shaft. The continuous filter band is inserted between the metal link belt - the carrier belt - and the filter wheels. This fabric filter belt is tensioned separately and moved by friction. The Filtration trough is sealed on all sides. The medium to be filtered is directed into the trough via the centrally positioned inlet pipe. The cleaned medium is transferred vertically down into the clean tank via separate outlets. An intentional turbulent zone at the infeed - arc screen effect - keeps the filter belt free of dirt deposits and hence permeable in this zone. The particles settle in the calm zone of the filtration trough where they form a filter cake. This filter cake serves as an additional filter layer. A pool forms slowly but surely as the particle deposits rise an the filter belt. Its level inside the filter can amount to as much as 400 mm, depending an the filter type. This high hydrostatic pressure enables optimum filtration. When a maximum level is reached inside the filtration trough, the geared motor switches on and moves clean continuous filter belt into place without interrupting the filtration process. The level in the filtration trough sinks and the belt transport device is switched off. At the same time the filtered sludge is discharged at the front. To process large quantities of sludge, separate sludge drivers similar to scrapers are fitted between the pulleys. They eject all the sludge and coarse chips without causing any damage to the filter belt. Outside the filter the continuous filter belt is wiped and flushed automatically so that it is free of deposits before returning to the filtration phase. This KBF design of filtration system has a proven record giving.