Air separating method, involves operating extracted nitrogen gas from high pressure column at pressure higher than pressure of systems operating at low pressure, and compressing gas till pressure is higher than high pressure of systems

摘要

The method involves compressing, purifying and cooling air in an exchange line (17), and separating the compressed air in a low pressure column (33) and a high pressure column (31) of a system by a cryogenic distillation. Flow of nitrogen gas is extracted from the column (31), and the extracted gas is compressed in a compressor (15). The extracted nitrogen gas from the column is operated at pressure that is higher than the pressure of the column systems operating at the low pressure. The compressed nitrogen gas is compressed till the pressure is higher than the high pressure of the systems. An independent claim is also included for an air separation device.