Process and device for obtaining a compressed product by low temperature separation of air

摘要

The process and device are used to obtain a compressed product by low temperature separation of air in a rectification system which has a pressure column and a low pressure column. A first flow of compressed and purified feedstock air is cooled in a main heat exchanger system and is fed into the pressure column. At least one fraction from the pressure column is expanded and fed into the low pressure column. An oxygen-rich fraction from the low pressure column is liquid-pressurized and delivered to a mixing column. A heat exchange medium is fed into the lower area of the mixing column and is brought into countercurrent contact with the oxygen-rich fraction. A gaseous top product is removed from the upper area of the mixing column. A product fraction is removed from the rectification system, liquid-pressurized, vaporized in indirect heat exchange with the gaseous top product of the mixing column and is withdrawn as the compressed product. Indirect heat exchange is carried out for vaporization of the liquid-pressurized product fraction in the main heat exchanger system.