Due to environmental problems, the concentration of N2O in the air is increasing. In addition, the electronic and other industries have higher and higher requirements on the purity of oxygen products (99.99% - 99.9999%), so the removal of N2O in the processing air is more important than in the past. A better method is to find a suitable molecular sieve and remove H2O, CO2, C2H2 and N2O in the process air by CO adsorption in the molecular sieve purifier.DEAR Air separation unit.The volume fraction of argon in air is 0.932%, and its boiling point is between oxygen and nitrogen. When it enters the lower column and rises block by block along the tray, because argon and oxygen are relatively nonvolatile components to nitrogen, they condense more into the liquid phase than nitrogen.Compared with gas leakage, liquid leakage is more harmful, because its unit cooling capacity is twice as large as that of gas at the same temperature, and the density of liquid is hundreds of times of that of gas. Taking liquid oxygen as an example, if the leakage occurs at the speed of 1l / min, the increased cooling loss is 27200kj / h = 7.6kw, and the expansion of 600m3 / h is needed to make up for it. In fact, the equipment can not work normally. Therefore, the leakage of liquid pipeline is absolutely not allowed.
The liquid air subcooler is blocked and the liquid air quantity is reduced, which makes the temperature of sewage nitrogen low and causes the air liquefaction at the cold end of the switching heat exchanger. When several expanders are running at the same time during the liquid accumulation stage of the start-up process, the cold capacity of the expander is too large, and the liquefier can not be fully recovered, the cold end of the accumulator (or switching heat exchanger) may also have air liquefaction.If the heat exchange effect of the air compressor end cooler (or nitrogen water precooler) is not good, or the cooling water temperature is high, the air temperature into the device will rise. If the air volume remains unchanged, the cooling capacity required to cool the air to near the liquefaction temperature will increase accordingly.Liquid oxygen is a kind of low temperature and strong combustion supporting material. There is a large amount of liquid oxygen stored in the liquid oxygen tank. In addition to preventing leakage and low temperature burns, we should also be alert to the risk of explosion.
DEAR Air separation unit.The main fault in the valve body is that the sealing surface between the valve top and the valve seat is not tight, which causes the valve not to close. The most common is the O-ring rubber seal off. This is mainly related to the uncleanness of the bonding surface and the poor quality of the adhesive. In addition, there are foreign matters at the valve seat; the concave convex spherical washers at both ends of the valve stem and the valve top are too tight or too loose; the fixed nut is not tightened, resulting in the loosening of the valve top; the bending of the valve stem may cause the valve to close loosely.DEAR Air separation unit.If the compression pressure of liquid oxygen is higher than the critical pressure (for example, the oxygen pressure for chemical industry is 6.0MPa or higher), there is no gasification stage with constant temperature in the gasification process of heat exchanger. This will affect the heat transfer performance of high-pressure heat exchanger, which should be fully considered in the design.
