Understanding of 3 typical air separation for oxygen
Air separation for oxygen will be the use of particular technical measures the oxygen and nitrogen from the air (a mixture) strategy of separating. Hence, the preparation of oxygen you can find two important categories of physical and chemical solutions, generally known as oxygen in physics and chemical oxygen. Physical oxygen atmosphere of raw materials, mostly utilizes the deep cooling technique, stress swing adsorption, membrane separation, and their combination of techniques.
1, the deep cooling method
Deep cold approach is initially will air compression, and cooling, and makes air liquefied, making use of oxygen, and nitrogen element of boiling point of distinctive (in atmospheric pressure Xia oxygen boiling point for 90 k, nitrogen boiling point for 77 k), in distillation column Board Shang gas, and liquid make contact with, for mass, and hot Exchange, high boiling point of oxygen component consistently from steam gas within the condensation into liquid, low boiling point of nitrogen element consistently to into steam gas amongst, makes rose of steam gas within the containing nitrogen volume continually to enhance, and dirty liquid in the oxygen volume increasingly higher, hence tends to make oxygen, and nitrogen separation, this really is air fine distillation. This method of air liquefaction and distillation, is carried out at temperatures below 120 k, it is also known as cryogenic air separation.
two, PSA
PSA-VPSA strategy, its simple principle is according to molecular sieves for oxygen and nitrogen in the air component of selective adsorption to oxygen-nitrogen separation major to oxygen in the air. When air is compressed, the adsorption of molecular sieve adsorption layer, nitrogen priority is absorption, oxygen molecules inside the gas phase by way of adsorption bed layer becomes oxygen. Dang adsorbent layer within the of nitrogen adsorption reached relative saturated Shi, working with decompression or pumping vacuum of technique will adsorbent molecular surface adsorption of nitrogen molecular solutions sucking out and sent bounds district emptying, tends to make adsorbent get options sucking once more recovery original of adsorption capacity, for Xia a cycle of adsorption made oxygen created ready, two a above (containing two a) adsorption Tower kept to cycle, on accomplished has continuous developed oxygen of purposes.
three, membrane separation method
With the improvement of synthetic polymer membrane, employing higher technology of membrane separation of substances be developed, increasingly wide selection of applications, and applications in food processing and fermentation broth extraction is specifically very valued internationally.
Organic vapor recovery technique applying "reverse" selective composite membrane. Inside the presence of some osmotic driving force, depending around the solution-diffusion of gas molecules in the efficiency variations, condensable organic vapor (like vinyl chloride monomer, ethylene, hydrocarbons, and so forth) and Non-Condensable gases (including hydrogen, nitrogen, methane, and so forth), adsorption and penetration by priority, so as to achieve the objective of separation. In industrial applications, the widespread membrane electrodialysis, micro filtration, ultrafiltration, reverse osmosis and nanofiltration for five.
Source:http://www.rich-china.com.cn/
