Process and device for producing a pressurized gaseous product by low-temperature separation of air

An apparatus for producing pressurized gaseous product by low-temperature separation of air in a distillation system, which has at least one high-pressure column (7) and one low-pressure column (8),

• With a main air compressor for compressing a process air stream,
• With means (6) for introducing at least one part of the compressed process air stream (1) into the high-pressure column (7),
• With a recompressor (11, 15, 111) for secondary compression of a first air stream (10, 13, 14, 17, 18), which is formed by at least one part of the process air stream (1), to a high air pressure that is at least 1 bar above the operating pressure of the high-pressure column (7),
• Removed with means for removing a liquid product stream (21, 47) from the distillation system, for increasing pressure (48, 51) in the liquid state, and for evaporating or pseudo-evaporating by indirect heat exchange (4) with the first air stream (17), and with a gas product line (50, 53) for drawing off the evaporated product stream as a gaseous product stream,
• Whereby the means for evaporating or pseudo-evaporating by indirect heat exchange (4) are designed as a means for condensing or pseudo-condensing the first air stream (17),
• With means (20) for evaporating the first air stream (18) downstream from the indirect heat exchange (4) with the product stream (49, 52), which is pressurized in the liquid state, in indirect heat exchange (20) with a gaseous stream (41) from the upper section of the high-pressure column (7),
• And with a return line (23, 26) for recycling the evaporated first air stream (22) into the process air stream (1, 2),
• the improvement comprising a recompressor (24, 124, 524) for compressing the evaporated, first air stream (23) upstream from where it is recycled into the process air stream.