Description
Filter presses in principal are pressure filters, wherein a pack comprising of a series of plates and frames (Polypropylene, Cast Iron or Aluminum) or chamber plates (1) (Recessed plates) is compressed between a fixed head (4) on one end and one movable bulk head (3) on the other end, that the movable bulk head is contacted to a hydraulic jack (8).
Filter pack is supported on two parallel tie bars (2) which are stretched between the fixed end (4) and the free end (3).
The filter press also consists of a skeleton to support the filter plates and a closure mechanism (7) to provide the necessary force on the sealing faces of the plates to counteract the applied force of filtration.
Operation
Filter presses are loaded with slurry before completing a filtering cycle and producing a batch of solid filtered material, called the filter “cake” (5). The solid is removed, the press re-loaded with slurry and the filtering cycle repeated. A filter press uses increased pressure to maximize the rate of filtration and produce a final filter cake with a low water content.
The filter plates are forced together with hydraulic ram that generates high pressures, and then the filter plates are loaded with slurry. In addition to the filter plate filtration medium, the growing cake enhances removal of fine particles in the slurry. The solution coming through the filter press water bibs, called the filtrate (6), will be very pure. The filtrate can be drained away for safe disposal, or it can be kept in a water tank for recycled use.
The cake, formed after the solid-liquid separation of slurry, will fall out once the pack is opened.
Once the filter cake is fully pressed and filtrate trickles are out, the cake can be washed to remove any impurities and can further be air dried.
