Home > News > Content
Ceramic Membrane Principle
Apr 13, 2018

Ceramic membrane separation technology is a kind of "cross-flow filtration" forms of fluid separation process: raw materials for high-speed flow of fluid in the membrane tube, the pressure driven by small molecular components of clarifying penetrants outward along the vertical direction through the membrane, intercept, cloudy concentrate capsule containing macromolecular components so that the fluid to achieve the purpose of separation, enrichment and purification.

Ceramic membrane is a ceramic carrier with a porosity of 30%~50%, a pore diameter of 50nm~15 m, and an asymmetric composite film made of sol-gel or other processes. The structure of the ceramic membrane used for separation is usually sandwiched: the supporting layer (also known as the carrier layer), the transition layer (also known as the middle layer), and the film layer (also known as the separation layer). The pore diameter of the supporting layer is 1~20 mm, and the porosity is 30%~65%, which is used to increase the mechanical strength of the film. The pore diameter of the middle layer is smaller than that of the supporting layer.

In the preparation process of the film, the penetration of the particles into the porous support layer is about 20~60, and the porosity is 30%~40%. The film layer has the function of separation. The pore diameter ranges from 0.8nm to 1 mu m, and the thickness is about 3~10 mu m, and the porosity is 40%~55%. The pore diameter distribution of the whole film decreases gradually from the supporting layer to the film layer, forming an asymmetrical structure distribution.

According to the pore diameter, ceramic membrane can be divided into microfiltration (pore diameter > 50nm), ultrafiltration (pore diameter 2~50nm), nanofiltration (diameter less than 2nm), etc. In the process of separation, under the action of external forces, small molecular substances penetrate the membrane, and the macromolecule material is trapped by the membrane, thus achieving the purpose of separation, concentration, purification, removal and sterilization.