Cartridge filter is a filter of negative pressure as the driving force is formed in the filtrate exit. This filter is divided into two kinds of intermittent operation and continuous operation. Intermittent operation of the filter to filter traffic suspensions at various concentrations, continuous operation of the cartridge filter adapted to filter solid particles containing more thick suspension. Intermittent operation of the filter because it can be automated to be developed, increasing filtration area. In order to obtain a low moisture content of the filter cake, the filter press machine has been developed. The container with a filter medium separated into upper and lower chambers, constitutes a simple filter. The suspension was added to the upper chamber, under pressure into the lower chamber through the filter media to become filtrate, the solid particles are trapped in the filter medium surface to form a residue. Filtration process residues accumulated in the filter medium surface layer gradually thickened liquid through the filter cake layer resistance will be increased, the filtration rate decreases. When the filter chamber filled with residue or filtration rate is too small, stop filtering, removing residue, the filter media regeneration to complete a filtration cycle. By residue layer and must overcome the resistance of the filter medium, so both sides of cartridge filter media must have a pressure difference, which is the driving force to achieve filtering. Increasing the pressure difference can accelerate the filtration, but the compressive deformation of the particles in a large pressure difference is easy to plug the filter medium pores, actually slows the bag filter.
