| 摘要 |
<p>Device to liquefy gases from gas mixts. has a separate cooling circuit to cool a refrigerant and also a cooling system through which the gas mixt. to be cooled flows, and a pre-cooler cooled by a refrigerant to precool the gas mixt. The device has a deep cooler to liquefy gases and a heat exchanger before the pre-cooler with cold gas from the cooling system flowing counter currently to the entering gas mixt. There are at least two independently operable deep coolers in the cooling system. Deep coolers can independently have pre-cooled or uncooled feed gas mixt. passed to them. There is a pipe and valve system which permits defrosting of one deep cooler whilst the other is in operation without loss of liquefying gas. Also claimed is a liquefaction process using the above device and the use of trifluoromethane to cool propellants, where it is compressed to 10-20, pref. 10-15 bar. The trifluoromethane is then cooled by indirect heat exchange with a refrigerant at -15 to -25, (-17 to -23) [deg]C. After cooling, the trifluoromethane is cooled by expansion to -55 to -115 [deg]C, pref. -80 [deg]C and used at this temp. to cool the propellants.</p> |
