The polypropylene diaphragm filter press adopts hydraulic or pneumatic pressure, with a maximum pressure of up to 2.5Mpa; The specialized variable filter chamber filter plate has successfully applied the patented technology of variable filter chamber diaphragm pressing to sludge dewatering in chemical, pharmaceutical, mining, and urban sewage treatment. It adopts a reinforced polypropylene lining plate and an integral fusion welded structure of rubber plastic elastic membrane, which has excellent chemical resistance and fatigue resistance, greatly improving its practicality in sewage treatment systems. Short filtration cycle, good filtration effect, and low moisture content of filter cake.