METHOD AND DEVICE FOR PRODUCING AIR GASES IN A GASEOUS AND LIQUID FORM WITH A HIGH FLEXIBILITY AND BY CRYOGENIC DISTILLATION

摘要

The invention relates to a method for producing at least one air gas by cryogenic distillation in a column system, in which: in a first operation mode, an auxiliary turbine (27) sucks a gaseous fraction of an air flow previously expanded in a first turbine (21), the suction pressure of the auxiliary turbine differing by less than 2 abs bars from the average pressure, the discharge pressure of the auxiliary turbine being higher than or substantially equal to the atmospheric pressure, wherein at least a portion of the air flow expanded in the auxiliary turbine is heated in an exchange line (7) and released into the atmosphere, and a portion (32) of the air components is produced as a final product in a liquid form; and in a second operation mode, the air flow processed in the auxiliary turbine is reduced and the production of liquid as a final product is reduced.