What is Membrane Separation?

Membrane separation is a new separation technology that appeared in the early 20th century and quickly rose after the 1960s. Membrane separation technology has the functions of separation, concentration, purification, and refining, and has the characteristics of high efficiency, energy saving, environmental protection, simple molecular-level filtration and filtration process, and easy control. Therefore, it has been widely used in food, medicine, biology, Environmental protection, chemical industry, metallurgy, energy, petroleum, water treatment, electronics, bionics and other fields have produced huge economic and social benefits, and have become one of the most important means in separation science today.

Membrane separation

Membrane is a material with selective separation function. The process of separating, purifying, and concentrating different components of a feed liquid using selective membrane separation is called membrane separation.

The difference between membrane separation and traditional filtration is that the membrane can be separated within the molecular range, and this process is a physical process without the need for phase changes and addition of additives.

The pore size of the membrane is generally in the order of micrometers, and the membrane can be divided into microfiltration membrane (MF),

(1) Under normal temperature

Minimal loss of active ingredients, especially suitable for the separation and concentration of heat-sensitive substances, such as antibiotics, medicines, juices, enzymes, and proteins

(2) No phase change

Keep the original flavor

(3) No chemical changes

Typical physical separation process without chemicals and additives, the product is not contaminated

(4) Good selectivity

Separation of substances at the molecular level, with outstanding performance that universal filter media cannot replace

(5) Strong adaptability

The processing scale can be large or small, and can be performed continuously or intermittently. The process is simple, the operation is convenient, and the automation is easy.

(6) Low energy consumption

It only needs electric power to drive, the energy consumption is extremely low, and its cost is about 1 / 3-1 / 8 of evaporation concentration or freeze concentration

Membrane separation technology refers to the

Microfiltration and ultrafiltration have limited molecular weight cut-offs for precision filtration

Membrane separation technology is classified according to the pore size, which are microfiltration, ultrafiltration, nanofiltration and reverse osmosis. Both microfiltration and ultrafiltration belong to precision filtration. Generally, the pore size of nanofiltration membranes ranges from 0.1 to 1 micron, and the pore size of ultrafiltration membranes ranges from 0.05um to 1nm. Characterization: Generally, the molecular weight cut-off range is 1000 ~ 300,000, the removal effect of small molecular organic pollutants is not obvious, and it can not meet the requirements of advanced treatment. At the same time, ultrafiltration equipment occupies less land, and the water flow can double. In today's tight urban land resources, ultrafiltration equipment has a very broad space in the process of water plant reconstruction and expansion. Membrane separation technology

Effective means for biological safety of ultrafiltration water

The first indicator of the water quality standard is the biological indicator (total coliform). Ultrafiltration can effectively remove bacteria and viruses, ensure water quality and biological safety, reduce the amount of disinfectant used in water treatment, and reduce secondary disinfection by-products. pollution problem. The turbidity of the effluent of the water treated by Toray Ultrafiltration Membrane is below 0.1 degree, which guarantees the safety of microorganisms.

The pore size of the nanofiltration membrane is a few nanometers, and the molecular weight of the nanofiltration membrane is in the range of 80-1000, and it has a certain rejection rate for inorganic salts. Reverse osmosis is the most advanced single treatment technology in the field of water treatment. It can block all soluble salts and organic matter with a molecular weight greater than 100. The quality of the effluent water after reverse osmosis treatment is better. Nanofiltration and reverse osmosis are effective means of advanced treatment, which can solve the problems of chemical pollution and organic pollution.

Microfiltration, ultrafiltration, nanofiltration, and reverse osmosis. These four types of membrane separation technologies all play an important role in the water treatment process. They are widely used in various water treatment terminal filtration, industrial water pretreatment and drinking. For the treatment of water, in the past ten years, China has made great progress in membrane modules and corresponding supporting equipment. Although there is a certain gap between the serialization and quality of varieties and advanced foreign technologies, domestic products have Replace the level of imported similar products. Membrane separation technology has been widely used and recognized in the fields of chemical industry, medicine, analysis and detection, and environmental protection, and has also achieved good economic, social and environmental benefits.