The suspension filtration has 3 kinds of residue layer filtration, deep filtration and sieve filtration.
1.residue layer Filtration: filtration medium can only intercept large solid particles, small particles with filtrate through the filtration medium. After the initial residue layer is formed, the residue layer plays a major role in the filtration, when large and small particles are trapped, such as filtration of the plate-frame filter press.
2.Deep Filtration: The filtration medium is thicker, the suspended liquid contains less solid particles, and the particles are smaller than the filtration medium. When the particles are filtered, they are adsorbed into the pores, such as filtration of porous plastic pipe filters and sand filters.
3. Sieve Filtration: The filtered solids are larger than the pore of the filtration medium, the solid particles are not adsorbed inside the filtration medium, such as the coarse-grained impurities in the sewage. In the actual filtration process, three kinds of methods are often simultaneously or successively appear.