| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a method for producing nitrogen by cryogenic distillation. <P>SOLUTION: Air containing carbon monoxide is sent to a cryogenic distillation column 5, a flow D of nitrogen is taken out of the top of the distillation column, with a CO content less than fixed value S1. A flow of nitrogen-rich cryogenic liquid coming from an external source 7 is sent to the top of the column. When the CO content in air does not exceed a predetermined threshold (S0), the flow rate of the cryogenic liquid sent to the column is set lower than a value V and, when the CO content in air exceeds the predetermined threshold (S0), the flow rate of the cryogenic liquid sent to the column is set equal to or larger than the value V. <P>COPYRIGHT: (C)2012,JPO&INPIT |
