In the condensing evaporator nitrogen is condensed at the same time, liquid oxygen is evaporated oxygen as the rising gas of the upper tower, and the upper tower of the reflux liquid rich oxygen liquid air, poor liquid air, dirty liquid nitrogen, liquid nitrogen by packing for heat mass exchange, in the condensing evaporator to get high purity liquid oxygen, in the middle of the upper tower to get argon containing argon 8 a 12% of argon fraction, by the argon making system can get high purity liquid argon. The nitrogen at the top of the upper tower is reheated through the cooler, the main heat exchanger (the air is cooled) out of the cold box below the top of the tower to pump out another part of the nitrogen, combined with a part of the nitrogen vaporised in the liquefier, reheated through the main heat exchanger, the raw air is cooled out of the cold box, then into the cold box in the high pressure heat exchanger, cooled to the appropriate temperature and pumped out, to the low pressure nitrogen press.
Dear Air's argon production system obtains a high quality argon product.