| 摘要 |
<p>A stream of permanent gas such as nitrogen at elevated pressure is cooled to below its critical temperature by heat exchange with work-expanded working fluid. The stream 2 is then further cooled in heat exchanger 4 and successfully flashed through at least three expansion valves 6, 12 and 16. Resulting flash gas is separated from liquid gas in separators 10, 14 and 18 respectively. The flash gas is passed through the heat exchanger 4 to provide cooling for such heat exchanger. By performing at three such successive isenthalpic expansions instead of the conventional one or two expansions, greater thermodynamic efficiency can be achieved enabling more favourable conditions to be set for the work expansion of the working fluid. </p> |
