In the operation process of the filter bag, the porous medium is mainly employed to effectively separate the suspension from the suspension. When the external force acts, the liquid in the suspension flows out through the pores of the medium, and the solid particles are discharged. It will be directly intercepted, which will achieve separation to some extent.
Under normal circumstances, the suspension to be filtered is effectively called a filter slurry. In the process of production, the porous medium is mainly used as a filter medium, and the liquid passing through the medium pore path is called a filtrate, and the retained solid matter is called Filter cake or filter residue.
Pressure difference of filter bag
1. Use the filter head itself.
2. Pressurize the surface of the filter.
3. Vacuum on the downstream side of the filter media.
4. Use inertial centrifugal force.
The role of filter bag
1. The pore size of the sieve filtration filter media is smaller than the diameter of the solid particles, and the solid particles are removed from the suspension by means of sieve analysis.
When the filter bag is subjected to sieve analysis and filtration in the initial stage of filtration, the fine particles flow out, so that the filtrate is relatively cloudy, and to a certain extent, the filtrate gradually becomes clear as the cake layer is formed and thickened. As the mesh is gradually blocked, the filtration rate tends to decrease. Filtration process When the cake layer is formed, the screening effect is generated by the cake layer, the filter medium loses the screening effect, and only plays the role of supporting the cake layer, which means that the cake layer is filtered.
2. Adsorption filtration (deep bed filtration): The mesh number of the filter medium is larger than the diameter of the solid particles, and the solid particles are adsorbed on the surface of the medium after entering the pores of the filter medium.