| 摘要 |
Air is separated in a double rectification column comprising a higher pressure rectification column, a lower pressure rectification column, and a first condenser-reboiler, of which the condensing passages communicate with an upper region of the higher pressure rectification column, and the reboiling passage communicate with a lower region of the lower pressure rectification column. A second condenser-reboiler is operated so as to reboil a liquid fraction obtained in the higher pressure rectification column. A stream of the air to be separated is partially or totally condensed by indirect heat exchange with a stream of nitrogen condensed in the first condenser-reboiler. At least part of the stream of condensed nitrogen is taken as product downstream of its heat exchange with the second stream of compressed air. |
