FIELD: technological processes.
SUBSTANCE: device serves for oxygen production by means of low-temperature decomposition of air. It has high-pressure column (1), low-pressure column (2) and main condenser (3). Column (31) for argon output is in hydraulic connection (32, 33) with intermediate place of column (2) of low pressure and is connected to head condenser (17) of column for argon output. Auxiliary column (140) has vat area, into which gas is introduced from head condenser (17) of argon column. Head part of auxiliary column (140) is connected to pipeline (136b) for return liquid for liquid flow input from high-pressure tower or main condenser. Said liquid stream has nitrogen content which is at least equal to that of air nitrogen. At least first part of liquid crude oxygen (16c) from cube of high-pressure column (1) is supplied to first intermediate place. Pressure in head part of auxiliary column is at least 50 mbar higher than pressure in head part of low-pressure column (2).
EFFECT: technical result is higher energy efficiency.
16 cl, 8 dwg
