Filter press machine in sand washing process belongs to mechanical dehydration equipment, which has the characteristics of low energy consumption, less dosage, high separation efficiency and high solid content of mud cake. Sand washing sludge treatment can be divided into two processes: sludge dewatering and sludge drying. Different types of filter press have their own advantages. A large amount of sludge will be produced after sedimentation treatment. Even after concentration and digestion treatment, the water content is still as high as 96%, and the volume is large, which is difficult to absorb and dispose. Therefore, dewatering treatment must be carried out to improve the solid content of sludge cake, so as to reduce the land occupation of sludge stacking.
The belt filter press is less affected by the fluctuation of sludge load. It also has the characteristics of low water content of sludge, stable operation, less start-up and consumption, relatively simple management and control, and low requirements for the quality of operating personnel. Compared with other types of dehydrators, the plate and frame filter press has higher solid content of sludge cake, up to 35%. If considering the factors of reducing the land occupation of sludge stacking, the plate and frame filter press is the preferred scheme. The moving mode of the filter plate requires that the operation can be completed by hydraulic starting device, automatic or semi-automatic operation, and the filter cloth oscillation device, so that the filter cake is easy to fall off.
Advantages of belt filter press: the belt filter press can treat the sludge that other filter presses cannot. Less energy consumption, less floor area, stable operation and long service life. The belt filter press can operate continuously.
Advantages of the plate and frame filter press: the structure of the plate and frame filter press is relatively simple, the operation is easy, the selection range of the filter area is flexible, the unit filter area occupies less land, the filter driving force is large, the moisture content of the filter cake is low, and the adaptability to materials is strong.