METHOD OF NATURAL GAS LIQUEFACTION BY THE CYCLE OF HIGH PRESSURE WITH THE PRECOOLING OF ETHANE AND NITROGEN "ARCTIC CASCADE" AND THE INSTALLATION FOR ITS IMPLEMENTATION Russian patent published in 2018 - IPC F25J1/00 

FIELD: gas production industry.

SUBSTANCE: invention relates to a natural gas liquefaction method. Method for liquefying natural gas consists in pre-cooling the prepared natural gas, separating ethane, supercool the liquefied gas with the use of cooled nitrogen as a coolant, reduce the pressure of the liquefied gas, separate the non-liquefied gas and withdraw the liquefied natural gas. In this case, before the preliminary cooling, the natural gas is compressed, the ethane is separated off in the process of multi-stage pre-cooling of the liquefied gas with simultaneous evaporation of ethane using cooled ethane as a refrigerant. Ethane, obtained by evaporation, is compressed, condensed and used as a coolant upon cooling of the liquefied gas and nitrogen, with nitrogen being compressed, cooled, expanded and fed to a supercooling step of natural gas.

EFFECT: invention is aimed at simplifying of the technological process of liquefying natural gas.

10 cl, 1 dwg