1、 Membrane separation method uses the permeability selectivity of some organic polymeric membranes. When air passes through the membrane (0.1um) or hollow fiber membrane, the speed of oxygen passing through the membrane is about 4-6 times that of nitrogen, so as to realize the separation of oxygen and nitrogen.
This method has the advantages of simple device, convenient operation, fast start-up and less investment. However, its oxygen concentration is relatively low, generally 28% - 35%, so it is generally used where the oxygen purity is not high.
2、 The principle of electrolysis method is to apply direct current in dilute sulfuric acid, sodium hydroxide or sodium sulfate aqueous solution to ionize water. Every 1m3 of oxygen is produced and 2m3 of hydrogen is obtained at the same time. However, because the power consumption for preparing 1m3 oxygen is 12-15 degrees, the power consumption is too large, and this method can not be produced in large quantities.
3、 Pressure swing adsorption molecular sieve oxygen generator is a kind of gas separation. Physical method (PSA method) directly extracts oxygen from the air, which is ready to use, fresh and natural. The oxygen generator is filled with molecular sieve, and the surface area of each gram of molecular sieve can reach 800-1000m2 / g. under pressure, nitrogen in the air is adsorbed by physical adsorption and desorption of molecular sieve, and the non adsorbed oxygen will be collected. Through purification treatment, oxygen with high purity can be obtained. Molecular sieve oxygen generator is mature at present. It has standard and standard oxygen generator, which can realize periodic circulating oxygen production. It is a dynamic process without high-pressure explosion and other risks.