Stainless Steel Plate and Frame Filter Press

Filter press usually uses filter cloth as filter medium, which is made of polypropylene filter cloth, non-woven fabric, cotton cloth, etc. filter paper board, cotton pulp board or filter membrane can also be used as filter medium as required. Generally, the cake thickness of plate and frame filter press can reach 50 mm, but in extreme cases, it can be increased to 200 mm. The box filter press (concave filter press) can form a filter cake with a thickness of 30-40mm.

Before using the filter press for filtration, if the solid suspension has precipitated, the mixed liquid needs to be pretreated, which can improve the performance of the filter press because it increases the porosity of the filter cake, thus speeding up the filtration speed. The size of floc can be controlled by changing temperature, concentration and pH value. In addition, if the filter cake is impermeable and not conducive to the flow of filtrate, filter aids can be added in the pretreatment process to increase the porosity of the filter cake, reduce the resistance of the filter cake and obtain a thicker filter cake. However, the filter aid needs to be able to be removed from the filter cake by physical or chemical treatment. A common filter aid is diatomite, with a porosity of 0.85.