| 摘要 |
<p>PROBLEM TO BE SOLVED: To obtain a cryogenic liquid which is free from fire hazard by a method wherein a nitrogen-rich mixture gas is mixed with compressed natural air cleared of moisture and carbon dioxide to obtain a mixture of gaseous products, which is cooled to a cryogenic temperature and liquefied. SOLUTION: Natural air A and nitrogen N are mixed in a ratio decided by the flow rate of nitrogen flowing through a flow rate control valve VB and flow through stop valves VA, VC. Once having been mixed, the mixture of gaseous products PG flows along a supply pipe 30 having a flow-rate indicator/regulator 32, an oxygen-analyzing regulator 34, a discharge valve VE, and a regulator valve VF. Ordinarily, the mixture of gaseous products PG is made to flow into a cooling machine 12 functioning as a cryogenic heat exchanger where the mixture of gaseous products PG undergoes heat exchange with a cryogenic cooling fluid CF, thus cooled and liquefied. This method enables obtaining a cryogenic liquid which is free from fire hazard.</p> |
