| 摘要 |
<p>The invention relates to a process for multi-component dual cooling for liquefying pressurized natural gas having a temperature of about -112 C (170 F). According to the invention, the process for multi-component dual cooling, for liquefying natural gas, uses two closed cycles, mixed or multi-component refrigerants, where a high-level refrigerant cools a low-level refrigerant and the low-level refrigerant is cooled and liquefies the natural gas. The natural gas is cooled and liquefied by indirect heat exchange with a multi-component low-level refrigerant, in a first refrigeration cycle. The low-level refrigerant is then heated by heat exchange in countercurrent with another flow of low-level refrigerant and by the heat exchange with a flow of high-level refrigerant. The heated low-level refrigerant is then compressed at a high pressure then cooled with an exterior cooling fluid. The low level cooler is then cooled by the heat exchange with a secondary flow of multi-component high-level refrigerant, and by the heat exchange with a low level cooler. The highe level cooler is heated by heat exchange with a low-level refrigerant. The high-level refrigerant is compressed at a high pressure and then cooled with an external cooling fluid.</p> |
