After the argon fraction is extracted from the top Tower, it enters into the crude argon tower and conducts the separation of oxygen and argon by the rectification method. Generally, the components of crude argon from the top of the crude argon tower are: argon is more than 98%, nitrogen is less than 0.5%, and oxygen is less than 1.5%. Import Crude argon with purity over 98% into molecular sieve adsorber. There are two adsorbers in each group. One is equipped with 5A Molecular sieve to absorb nitrogen in crude argon; the other is equipped with 4A molecular sieve to absorb oxygen in crude argon. In order to release the adsorbents, two groups of adsorbents need to be set up to switch to use. The adsorber works at the temperature of 90 K. The crude argon enters into 5A Molecular sieve adsorber to remove nitrogen first, and then enters into 4A molecular sieve adsorber to remove oxygen. The process is shown in Figure 18. The gas from a group of molecular sieve adsorbers has a purity of 9...