NATURAL GAS LIQUEFACTION PLANT THAT USES MECHANICAL COOLING AND LIQUID NITROGEN COOLING Russian patent published in 2021 - IPC F25J1/00 

FIELD: liquefaction systems.

SUBSTANCE: invention relates to the production of liquefied natural gas. The natural gas liquefaction system comprises a natural gas inlet, a liquid nitrogen inlet, a refrigerant inlet, a gaseous refrigerant outlet located at a lower pressure than the refrigerant inlet, a liquefaction unit communicating through a fluid medium to receive natural gas, liquid nitrogen, and incoming and outgoing refrigerant flows, which also includes at least one turbine, which receives the incoming refrigerant flow and releases the refrigerant flow at a reduced temperature and at a reduced pressure. The incoming flow to at least one turbine can be pre-cooled inside the liquefaction plant to a temperature lower than the ambient temperature. The liquefaction unit accepts a low temperature and pressure refrigerant fluid, which is further heated in the treatment area and discharged from the liquefaction unit as outgoing gaseous refrigerant flow; and has a liquefied natural gas outlet connected to the liquefaction unit.

EFFECT: reduced capital and operating costs.

9 cl, 4 dwg