| 摘要 |
<p>An air separation unit comprises a medium-pressure column (39), a low-pressure column (41), an enclosure (141), a heat exchanger (13), a bottom condenser (25) of the low-pressure column and a condenser (15) placed in the enclosure, a line for sending compressed, purified and cooled air from the heat exchanger to the medium-pressure column, a line for sending a heat-generating gas to the condenser placed in the enclosure, a line for sending a nitrogen-enriched gas from the medium-pressure column to the condenser of the low-pressure column, a line for sending an oxygen-enriched stream from the bottom of the medium-pressure column to the low-pressure column, a line for sending oxygen-rich liquid from the bottom of the low-pressure column to the enclosure, a line for withdrawing from the enclosure a fluid richer in oxygen than that sent to the enclosure, a line for sending a gas from the enclosure to the low-pressure column, and a line for withdrawing an overhead gas from the low-pressure column, characterized in that the unit includes an expansion means (51) for expanding the oxygen-rich liquid downstream of the bottom of the low-pressure column and upstream of the enclosure and a compressor (21) for compressing the gas from the enclosure, said compressor being downstream of the enclosure and upstream of the low-pressure column.</p> |
