METHOD FOR LIQUEFACTING NATURAL GAS AND RECOVERING LIQUID EVENTS OF NATURAL GAS COMPRISING TWO NATURAL GAS SEMI-OPENING REFRIGERANT CYCLES AND A REFRIGERANT GAS REFRIGERANT CYCLE

摘要

The invention relates to a process for liquefying a natural gas comprising a mixture of hydrocarbons, mainly methane, the process comprising a first natural gas semi-open refrigeration cycle in which the natural gas liquids which have been condensed are separated from the natural gas feed stream, the latter then passing through a main cryogenic heat exchanger (4) to contribute by heat exchange to the pre-cooling of a main stream of natural gas (FP) and to the cooling of a stream initial refrigerant gas (G-0), a second semi-open natural gas refrigerant cycle to assist in the pre-cooling of natural gas and refrigerant gas and the liquefaction of natural gas, and a closed gas refrigerant cycle refrigerant to subcool the liquefied natural gas and provide additional refrigeration power to the other two cycles. The invention also relates to a liquefaction plant for natural gas for the implementation of such a method.