Selection principles of industrial filter cloth in centrifugal filtration

The centrifuge is a widely used filtration device for industrial filter cloth, extensively applied in various fields such as the chemical industry. Typically, centrifuges utilize industrial filter cloth as the filtration medium. Through my long-term use, I have gained some insights into this:

1. When using industrial filter cloth as the filtration medium for centrifuges, a metal lining mesh is installed in the drum, and the filter cloth is laid on the lining mesh and fixed. Due to the softness and low strength of industrial filter cloth, the mesh size of the lining mesh should be smaller to effectively support the filter cloth and smoothly discharge the filtrate. The filter cloth is required to have sufficient strength, suitable pore size and porosity, corrosion resistance to the processed material, and a certain degree of wear resistance. There are three weaving methods for filter cloth: plain weave, twill weave, and satin weave. The plain weave method is the most compact, followed by the twill weave, while the satin weave method is sparser, and the porosity increases in sequence. The selection of industrial filter cloth should be determined through experiments, and the characteristics of various filter cloths are as follows:

A、 Cotton filter cloth: It has good mechanical strength, wear resistance, and temperature resistance, with small pores and is not affected by cold dilute acid.

B、 Nylon filter cloth: high tensile strength, particularly good wear resistance, smooth surface, easy slag discharge, can resist most alkalis and any concentration of organic acids.

C、 Polyester filter cloth: Good strength and wear resistance, particularly strong acid resistance, and good alkali resistance.

D、 Polypropylene filter cloth: It has good wear resistance and temperature resistance, good corrosion resistance to inorganic acids, strong corrosion resistance to weak bases and strong bases at room temperature, and is not dissolved in sulfuric acid with a concentration below 80%.

E、 Nylon filter cloth: It has corrosion resistance to alkali and inorganic acids at room temperature, is low in price, but has weak fibers and poor strength.     

F、 Polyvinyl chloride filter cloth: It has good corrosion resistance to various concentrations of strong acids and high temperature concentrated alkalis, with a smooth surface and easy slag discharge.

2. The mesh size (model) of industrial filter cloth is determined according to the diameter of the separated material. Generally, when selecting the mesh size of the filter cloth, it should be slightly larger than the diameter of the particles to be intercepted. In the primary stage of filtration, a small number of small particles pass through the filter. When the larger particles intercepted form a filter cake layer, the phenomenon of passing through the filter can be eliminated, which helps to improve the filtration efficiency.

3. It is recommended to use single filament double-layer composite filter cloth for industrial filter cloth, with the filtering surface treated by calendering to reduce the possibility of filter cloth blockage and improve the regeneration performance of industrial filter cloth.