Porous ceramics and filter main feature

The porous ceramic is a kind of refractory materials as aggregate, binding agent with the ceramic filter material after high-temperature sintering and made its internal structure has fine pores through a lot of inertia of a controlled pore size. In addition it has a high temperature, high pressure, acid and alkali corrosion properties, but also has uniform pore size, permeability characteristics. It can be widely used as filtration, separation, gas distribution and sound deadening material. Foreign Since the 1950s, began to make use of the porous ceramic filter element, the water purification, sterilization of mineral water, oil, gas purification. Up to now, the products have been standardized, serialized. Application of domestic porous ceramic filter in art despite a late start. But the porous ceramics as a filter element consisting of ceramic filters, separators in various sectors in the field of purification have been more comprehensive application. Such as the petrochemical industry, liquid-solid, gas-solid separation, pharmaceuticals, brewing industry sterile purification treatment, environmental protection industry in the high temperature flue gas dust removal. At present, the ceramic filter with its unique features, in the separation, purification has become an irreplaceable product.

The porous ceramic filter element.

Porous ceramic filter material performance.

The porous ceramic material, size and variety. Wherein the foreign production of a porous ceramic material pleases material mainly aluminum silicate, clay, corundum, quartz, silicon carbide and diatomaceous earth quality and the like. Domestic production mainly corundum, quartz and diatomaceous earth quality.

Aperture: show products open pore size, here is the maximum diameter of the opening article. The porous ceramic filter element pore size can be divided into 1,5,10,20,30,50,80,100,120,150,200,250,300Lm series.

Porosity: pore volume of the total article volume percentage opening opening V / V total × 100%.

Permeability K: refers 1mmH2O under pressure, in a unit time lh through the thickness of lcm, the amount of dry gas area of the porous ceramic 1m 2 (m 3).

Acid resistance: Porous ceramic products with a 20% sulfuric acid solution after boiling 1h flexural strength and flexural strength than before corrosion.

Alkaline: Porous ceramic products by 20% N aOH solution boiled fee 1h after the bending of the bending yo percentage strength before corrosion.

Temperature resistance: Porous ceramic products ability to resist changes in temperature without damage.

The main features of porous ceramic filter material.

Compared with other filtration materials, porous ceramic as a filter material having the following characteristics.

1. Porous ceramic filter material porosity, up to 60%. Uniform pore size and easy to control. High filtration precision up to 011Lm, for a variety of precision filter media.

2. Acid and alkali resistance. Suitable strong acid (sulfuric acid, nitric acid, hydrochloric acid), alkali (hydrogen chloride and the like) and various filtering organic solvents.

3. High mechanical strength, working pressure up to 6M Pa, pressure of up to 1M Pa.

4. High temperature, good thermal quench acute performance, operating temperature up to 800 ℃. For a variety of high temperature gas filtration.

5. Clean the filter element itself state, non-toxic, tasteless, no foreign matter off, suitable for aseptic processing operations.

6. Filter element long life, long-term use, a microporous morphology does not change, easy to clean regeneration.

The porous ceramic filter element filtration principle

Porous ceramic filter is set 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.

Inertial collision: the fluid flows through the porous ceramic filter element in the microporous channels of foreign particles, due to inertia in contact with the porous cell wall and is captured. 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 porous ceramic ceramic particles due to inertia and by the influence of Brownian motion and leave the flow lines and microchannel wall contact, still Most particles have been trapped in the surface or deposited on the porous ceramic pores. Since the porous ceramic tortuous microporous channels, plus bridging effect and inertial collision fluid medium formed on the surface of the porous ceramic Brownian motion and impact. So the filter itself much higher precision than the aperture. Such as 10Lm pore porous ceramic filter element when the filter medium is a liquid, the filtration accuracy 1Lm when the filter medium is a gas, the filtration accuracy of 0.5Lm.

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 a porous ceramic filter element life.