| 摘要 |
<p>A METHOD AND A SYSTEM FOR LIQUEFYING A GAS, IN PARTICULAR A NATURAL GAS The invention relates to a method of liquefying a gas, in particular a natural gas by cooling it under pressure in stages, of the kind comprising cooling the gas by means of at least two refrigerants, one refrigerant circulating in a closed refrigeration circuit and another refrigerant circulating in another closed refrigeration circuit, wherein the compositions of the various refrigerants differ from each other. According to the invention a compressor in a closed refrigeration circuit is driven by a gas turbine and the refrigerant circulating in the last mentioned closed refrigeration circuit is cooled by ambient air after compression. Furthermore, according to the invention, in addition to the compressor an electricity generator is driven by the gas turbine in such a manner that, when extra gas turbine power is available because of a variation of the ambient air temperature, so much electric power is generated that the gas turbine is caused to operate at, or at about, its design load. Said electric power is passed to an auxiliary electric motor coupled to a compressor with driving means in another closed refrigeration circuit, so as to deliver extra driving power to said compressor. The invention relates moreover to a system for carrying out the method according to the invention (see drawing).</p> |
