The plate and frame filter press is a device used for sludge treatment in sewage treatment systems and is a commonly used device in the sludge treatment process.

How does a plate and frame filter press work?

A plate and frame filter press consists of five main components: filter plates, a hydraulic system, a filter frame, a plate transport system, and an electrical system. The operating principle of a plate and frame filter press is relatively simple. Hydraulic pressure compresses the plate and frame assembly, allowing settled sludge to enter through the center and be distributed between the filter cloths. The tight compression of the plates and frame prevents the sludge from escaping. Under the high pressure of the screw pump and diaphragm pump, moisture in the sludge seeps through the filter cloths and flows into the return pipe, while the sludge cake remains in the cavities. The plates and frames are then decompressed, the filter plates are pulled apart, and the sludge cake falls by gravity and is removed by truck. Therefore, the filtration process is the final step in the wastewater treatment process. A video explaining the principle is provided:

Plate and frame filter presses are suitable for highly compressible or nearly incompressible suspensions. Suitable suspensions typically have a solids concentration below 10%, and operating pressures range from 0.3 to 0.6 MPa, though some can reach 3 MPa or higher. The filtration area can be increased or decreased depending on the number of plates and frames used. Plates and frames are typically square, with inner side lengths ranging from 320 to 2000 mm and frame thicknesses from 16 to 80 mm. The filter area ranges from 1 to 1200 square meters. The plates and frames are clamped together using manual screws, electric screws, or hydraulic pressure. Plates and frames can be made from wood, cast iron, cast steel, stainless steel, polypropylene, and rubber.