Basic principle of filtering

Filtration is the process of separating a solid material from a liquid. The basic principle is to use an object with many capillary pores to pass liquid through the capillary pores and trap the solids in the suspension on the medium. The tubular vacuum filter is filtered using a filter cloth as a filter medium. The slurry was placed on the filter cloth, and the underside of the filter cloth was evacuated by a vacuum pump, thereby forming a pressure difference on both sides of the filter cloth. Under the action of this pressure difference, the liquid in the slurry permeates the filter cloth into a filtrate, and the solid particles in the slurry are retained on the filter cloth to form a filter cake. As the time elapses, the thickness of the filter cake increases, and finally the scraper is scraped off to complete the dehydration work. In the ore dressing production, the filtration operation is carried out continuously.
The movement of the filtrate through the filter cake and the filter medium can basically be regarded as a laminar flow of the liquid through the capillary under pressure. According to the Pultierer equation of liquid movement through the capillary, it can be expressed as:

Where v - filtration speed, m / s;
F——filtration area, m ² ;
V - filtrate volume, m ³ ;
t - the corresponding filtration time of the volume V filtrate is obtained, seconds;
P——the pressure difference between the ends of the capillary, kg/ ^m2 ;
Μ——liquid viscosity, kg•second/ ^m2 ;
H——the thickness of the filter cake, m;
Ρ0——the resistance of the filter cake per unit volume, 1/ ^m3 ;
R0 - the resistance per unit area of ​​the filter medium, 1 / m ² .
The above formula indicates that the rate at which the filtrate passes through the filter surface is proportional to the pressure difference across the capillary, inversely proportional to the viscosity of the filtrate and the resistance of the filter cake and filter media. The above formula can be used to qualitatively explain the relationship between various factors in the filtration process, thus providing theoretical analysis and guidance for the actual operation of the filter.

Gas Protection Welding Wire

The gas protection Welding wire is a type of copper-plated low alloy steel gas shielded welding wire, using carbon dioxide or argon-rich as the shielding gas for welding. It has excellent welding process performance, stable arc combustion, less spatter, beautiful weld forming, small sensitivity of weld metal porosity, good welding technology in all position, and can be suitable for a wide range of welding current.