Air separation technique

Abstract

The invention belongs to the field of air separation and discloses an air separation technique. The problem of low purity of oxygen produced through an existing air separation technique is solved. The technique includes the steps that (1) air is filtered and enters an air compressor to be compressed, and the compressed air is cooled and washed in a cooling tower; (2) part of purified air is cooled to a dew point and then enters the bottom of a lower tower, the other part of purified air flows into a booster compressor to be pressurized, the pressurized air is divided into two ways, one way of air is subjected to expansion cooling and delivered into an upper tower, and the other way of air passes through a heat exchanger and flows into the lower tower; (3) the air is subjected to preliminary rectification in the lower tower, liquid air passes through a supercooler and then enters the upper tower, part of liquid oxygen is delivered into a storage system, and the other part of liquid oxygen is reheated and then enters an oxygen pipe network; and (4) argon distillate is extracted from the middle of the upper tower and delivered into a crude argon column, and pure nitrogen extracted from the top of the upper tower of a rectifying tower passes through the supercooler, then enters the heat exchanger and is delivered into a water-cooling tower and a user pipe network. By means of the air separation technique, the purity of produced oxygen reaches 99.8%.

Description

technical field [0001] The invention belongs to the field of air separation, and in particular relates to an air separation process method with a high oxygen extraction rate. Background technique [0002] The main components in the air are oxygen and nitrogen, which exist in the air in a molecular state. The air separation process is the process of condensing air into liquid by cryogenic rectification, and then separating the components in the air mixture according to the evaporation temperature of each component, so as to obtain high-purity oxygen, high-purity nitrogen and some rare gases. . [0003] The existing industrial air separation mainly includes adsorption method, membrane separation method and low temperature method. Among them, the adsorption method uses the selective adsorption performance of molecular sieves to different molecules to separate the components in the air. The adsorption method has a simple process and is easy to operate. , low operating cost, bu...

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is to provide an air separation process in order to solve the problem that the oxygen purity produced by the existing air separation process is not high.