Porous ceramic filter element filtration principle

Microporous ceramic filters is a adsorption, surface filtration and depth filtration way a filter combination. Kennedy at the liquid-solid, gas-solid filtration and separation system in terms of its filtering mechanism is mainly inertia collision, diffusion and interception.

Impurity particles, which are captured by inertia into contact with the porous cell walls. Square inertial collision with an impurity particle diameter is directly proportional to flow rate and fluid viscosity.

Diffusion: impurity particles due to the Brownian motion and leave the flow lines and pores of the cell wall in contact so as to be captured. Diffusion is inversely proportional to the flow rate and the capture and fluid viscosity.

Interception: impurity particles due to the large pores than the pores are captured, is a surface filtration. Interception sizes only foreign particles, whereas the flow velocity, the fluid viscosity does not matter.

When the fluid flows through the porous ceramic filter element, the filter element is greater than the pore size of the particles are trapped in the surface of the cake layer is formed smaller than the aperture of the ceramic porous ceramic particles due to inertia and by the influence of Brownian motion and leave the flow lines and microchannel wall contact , still some particles are trapped in the surface or deposited on porous ceramics tunnel. Since the porous ceramic tortuous microporous channels, plus bridging effect and inertial collision fluid medium in the porous ceramic surface and the influence of Brownian motion, so the filtration precision than the aperture itself higher. Such as 10μm pore porous ceramic filter element when the filter medium is a liquid, the filtration accuracy of 1μm when the filter medium is a gas, the filtration accuracy of 0.5 microns.

After the ceramic filter run for a certain period, since the filter element may be blocked through internal fluid medium particulate impurities, the surface of the cake layer thickness, resulting in filter resistance increases, the flow rate decreases by gas cleaning, gas or liquid backwash a liquid shuffled reproduce, leaving a basic recuperative to the initial state level.

Thus the timing cleaning backwash, can greatly extend the life of microporous ceramic filter element.