How does a plate-and-frame filter press separate solids from a slurry?

A plate-and-frame filter press separates solids from a slurry through a batch-operated pressure process. The device consists of a series of rigid plates and hollow frames assembled in a supporting framework, with filter cloths positioned between them.123

The assembly is tightened using a screw press, creating a secure seal. The slurry is then piped under pressure into the device through ports, typically located in the corners of the plates. As the slurry is forced against the filter medium, the liquid (filtrate) passes through the cloth and is removed via recessed channels and additional ports, while the solid matter is retained, collecting as a filter cake within the hollow frames.213

Once sufficient cake has accumulated, the process can include a washing stage by pumping water through the filter. Finally, the pressure is released, the plates are separated, and the accumulated filter cake is removed manually. This method is highly effective for handling slurries with high concentrations of suspended solids.2