In the 1950s, due to the popularization and application of oxygen-blowing steelmaking and blast furnace blast technology and the rapid development of the nitrogen fertilizer industry, air separation equipment was developed to large-scale, and modern scientific research results were applied, such as the use of turbo compressors and turbine expansion.
After the equipment, plate-fin heat exchangers, microcomputers and molecular sieve adsorbers, the air separation equipment has been continuously improved and perfected. The air pressure in the equipment has dropped from high pressure (20 MPa) to low pressure (less than 1 MPa), The power consumption per unit product has also gradually decreased (the power consumption per cubic meter of oxygen has dropped from 1.5 to 0.6 kW·h). Modern air separation equipment can produce gaseous or liquid products of various capacities and different purity, and can also produce ultra-high purity oxygen and nitrogen (such as 99.998% oxygen and 99.9995% nitrogen). The air separation equipment can also be based on the needs of users. Through the control of the electronic computer, the number of products can be increased or decreased at any time to achieve the purpose of economic oxygen use. By the 1980s, the oxygen production capacity of large-scale air separation equipment had reached 70,000 meters (/hour; the air pressure dropped to 0.36 MPa; the continuous operation period could reach more than 2 years.
