Filtering Mechanism and Influencing Factors of Filter

The filter is related to the characteristics of the fluid. For example, the fluid viscosity and chemical / ionic components, the greater the viscosity of the fluid under the same pressure conditions, the slower the flow of fluid and the membrane has more contact between the filter better; another example, the fluid and membrane mixing / The contact time also has a great impact on the filtration effect, the longer the mixing / contact time, the better the filtration effect. In addition, it should be noted that the characteristics of the fluid only affect the film on the fluid adsorption retention effect without affecting the particle size of the exclusion.

Filter particle type and filter effect also has a great relationship, the particles are divided into deformable particles and non-deformable particles 2 species. Under certain pressure, the deformable particles will enter the filter membrane and lead to more filter mesh clogging, thus affecting the filtering effect, such as gel filtration. However, when the immobile particles are filtered, they form a layer of cake-like material on the filter.

The filter is related to the actual operating conditions, such as particle flow rate and filtration pressure. In order to obtain good filtering effect, generally choose a lower flow rate, the lower the flow rate the better the retention effect. Practice has proved that the structure of membrane movement is unfavorable to the filter, once the membrane structure in the filter process has changed, the particles and fibers can be precipitated from the deep filter, affecting the filtering effect. However, the velocity / pressure difference only has a significant effect on the adsorption entrapment, and the effect on size exclusion is rather small.