Membrane separation technology mainly uses nanofiltration membranes with a molecular weight cut-off of 100 to 1000 Dal in the concentration and purification process. The main feature of nanofiltration membranes is that the retention performance of divalent ions, functional sugars, small molecule pigments, peptides and other substances is higher than 98%, and for some monovalent ions, small molecule acids and bases, alcohols, etc., it has 30-50%. Its permeability is often used in the separation, purification, and concentration processes of solute classification, elution of low-molecular substances in solution, adjustment of ionic components, and concentration of solution systems.

　　Nanofiltration membrane separation technology is often used to replace traditional processes such as freeze-drying, thin-film evaporation, ion exchange desalination, resin process concentration, and neutralization. Source: Guteng Water Network

　　The main membrane modules that can be used in the concentration and purification technology are: roll membrane and tubular membrane.

　　The advantages of concentration and purification using nanofiltration membrane separation technology:

　　1), extremely low energy consumption, saving the cost of the concentration process;

　　 2) There is no chemical reaction, no phase change in the process, no other impurities and no decomposition and denaturation of the product;

　　3), achieve the purpose of concentration and purification at room temperature, without causing damage to the active ingredients, and the process yield is high;

　　4), can completely remove the salt of the product, reduce the ash content of the product, and improve the purity of the product;

　　5) Acid, alkali, alcohol and other substances in the solution can be recovered;

　　6), the equipment structure is simple and compact, and the floor space is small;

　　7) Easy operation, automatic operation, good stability and easy maintenance.

　　 Part Three-Industry Application

　　 1. Pharmaceutical industry

　　● Filtration and sterilization of biological fermentation broth and downstream separation, purification and refinement

　　● Concentration of resin analysis solution and recovery of analysis agent

　　● Production and application of pesticide water and powder

　　● Filtration and concentration of Chinese medicine extract

　　● Production and Application of Chinese Medicine Extract

　　● Desalination and concentration of synthetic drugs, bulk drugs, intermediates, etc.

　　● Recovery of crystallization mother liquor

　　 2. Food industry

　　● Whey wastewater treatment

　　● Dairy production and processing applications

　　● Juice clarification and decolorization

　　● Purification and concentration of food additives

　　● Tea beverage clarification and concentration

　　● Refined processing of beer, wine and rice wine

　　● Removal and concentration of natural pigment extract

　　● Amino acid fermentation broth filtered, clarified and refined

　　3. Dye chemicals and additives

　　 Desalination and concentration of water-soluble dye reaction solution

　　● Dye salting-out mother liquor wastewater recovery

　　 Four, starch candy

　　● Separation, purification and concentration of sugar liquid

　　● Fructose syrup color Pu separation and purification

　　● Separation and purification of sugar alcohol

　　● Separation, purification and concentration of monosaccharides, oligosaccharides and polysaccharides

　　 5. Environmental protection and water treatment

　　● Textile, dyeing and finishing, printing and dyeing wastewater treatment and reuse

　　● Zero discharge of electroplating industrial wastewater and resource recovery

　　● Mine and metallurgical wastewater treatment and recycling

　　● Starch wastewater treatment

　　● Papermaking wastewater lignin recovery and wastewater treatment

　　● Electrophoretic paint wastewater paint recovery

　　● Acid and alkali wastewater treatment and recycling

　　● Treatment and reuse of municipal sewage

　　● Cycle treatment of car wash water, sauna water, swimming pool water, bathing wastewater, etc.

　　● Various types of softened water, pure water, and ultra-pure water used in industrial production

　　 VI. Biotechnology

　　● Filtration, clarification and purification of fermentation liquids such as biological proteins, peptides, and enzyme preparations