Views: 3 Author: Site Editor Publish Time: 2021-03-29 Origin: Site
The research of inorganic ceramic membrane began in the 1940s, and made a breakthrough in the late 1980s. The research of inorganic ceramic membrane and separation technology started late in China, but the development speed is fast. Due to the advantages of high efficiency, high temperature resistance, reliable operation and good chemical stability, the prospect of inorganic ceramic membrane technology is very broad. Compared with polymer organic membrane, inorganic ceramic membrane has the following characteristics.
a. The pore size distribution of inorganic ceramic membrane is narrow, and its distribution is normal, and the pore size within ± 10% accounts for more than 80%, such as 0.05 μ m membrane, and the pore size between 0.049 μ m-0.051 μ m accounts for 80% of the total pore size of all membranes, which ensures the stability of the membrane treatment effect. This is quite different from organic membrane, and the pore size distribution of organic membrane is generally characterized by molecular weight interception Generally, the average distribution is dominant.
b. The porosity of inorganic ceramic membrane is 35% - 40%, which ensures high membrane flux.
c. The structure of inorganic ceramic membrane separation layer is more reasonable. There are four layers of separation layer and support layer, with pore sizes of 5-10 μ m, 1.0 μ m, 0.6 μ m and 0.2 μ m, respectively. The gradient membrane or asymmetric membrane is formed in the true sense, which improves the anti pollution ability of the membrane. The separation layer is thinner, 20 μ m thick, and the membrane cleaning is more simple and convenient, Strict pretreatment is needed for membrane feeding.
d. The strength of the inorganic ceramic membrane is high, the maximum pressure of the membrane can be 16 bar, and the maximum pressure of the support body can be 30 bar, which is not easy to damage, ensuring the effect of membrane treatment and the stability of treatment quality.
e. Inorganic ceramic membrane has high insulation performance.
f. The service life of inorganic ceramic membrane is longer than 5 years, while that of organic membrane is 3 ~ 6 months.
g. The chemical stability (pH range is 0 ~ 14) and thermal stability (up to 400 ℃) of inorganic ceramic membrane are better than those of organic membrane. Strong acid, strong alkali and strong oxidant can be used as cleaning agent, which makes cleaning and regeneration more convenient and easy, and steam sterilization can be carried out directly. However, organic membrane can not operate under the conditions of high temperature, strong alkali, strong acid and strong oxidant.