Mechanical filter (quartz sand filter), also known as the pressure type filter, more steel cylindrical equipment, the internal with the water device, water and drainage device, the external pipe, instrumentation and valves, etc.. Mechanical filter in a certain pressure to run: with the pump will be treated with water into the filter, the filtered water can be used to follow the process. When the filter is dirty, the pressure difference between inlet and outlet is increased, and the filter layer can be used to filter the filter layer, so that the filter layer can be capable of intercepting suspended solids.