The hydraulic pressure mechanism of the filter press is composed of a hydraulic station, a cylinder, a piston, a piston rod, and a Huffland card hydraulic station where the piston rod is connected to the pressure plate. Direction valve, pressure gauge, oil circuit, fuel tank. Filtration method: The method of filtrate flow is clear flow filtration and dark flow filtration. Open-flow filtration. A water nozzle is installed on the outlet hole below each filter plate, and the filtrate flows out intuitively from the water nozzle. Underflow filtration, a liquid outlet channel hole is provided under each filter plate, and the liquid outlet holes of several filter plates are connected to form a liquid outlet channel, which is discharged through a pipe connected to the liquid outlet holes below the thrust plate. Washing method: When the filter cake needs to be washed, there are sometimes one-way washing and two-way washing, and underflow one-way washing and two-way washing.