What are the common membrane separation technologies and which fields are they suitable for?

Membrane separation technology is a new separation, purification and concentration technology with high efficiency and energy saving without phase change at room temperature. Its basic principle is to use natural or synthetic membranes with selective permeability to separate, classify, purify or enrich binary or multicomponent systems driven by external energy or chemical potential difference, which can be used in liquid and gas phases.

For liquid phase separation, it can be used in aqueous system, non-aqueous system, hydrosol system and aqueous system containing other particles. Separation membranes are mostly solid (most membrane materials are organic polymers at present) or liquid. What they have in common is that they can selectively penetrate the systems separated by them. Next, Deramaix Le Bianxiao introduced the characteristics of common membrane separation technology.

According to the types of membranes, they can be divided into microfiltration, ultrafiltration, reverse osmosis, nanofiltration, dialysis, electrodialysis, pervaporation and gas separation.

Characteristics of common membrane separation technologies;

There is no phase change in the separation process of (1) membrane, and compared with the separation method with phase change and other separation methods, the energy consumption is lower.

(2) The membrane separation process is carried out at normal temperature, so it is especially suitable for the separation, classification, concentration and enrichment of heat-sensitive substances, such as juice, enzyme, medicine, etc.

(3) Membrane separation technology is not only suitable for the extensive separation of organic and inorganic substances, from viruses and bacteria to particles, but also suitable for the separation of many special solution systems, such as the separation of macromolecules and inorganic salts in solutions, and the separation of some substances with boiling point or near boiling point.

(4) Because only pressure is used as the driving force for membrane separation, the separation device is simple and easy to control and maintain.