UNITED MULTIPLE-LOOP COOLING METHOD FOR GAS LIQUEFACTION Russian patent published in 2007 - IPC F25J1/02 

FIELD: refrigeration and cryogenic equipment.

SUBSTANCE: gas liquefaction method involves serially cooling supply gas flow in through heat-exchanging zones working in the first, the second and the third temperature ranges correspondingly. The supply gas flow is cooled in the first temperature range by means of the first evaporative coolant. The supply gas flow is cooled in the second temperature range by means of the second evaporative coolant. The supply gas flow is cooled in the third temperature range by means of the third evaporative coolant in cooling loop. The first, the second and the third coolants have different compositions. Coolant, which provides cooling in the coolest heat-exchanging zone, comprises part of the third coolant, which is cooled by evaporation at temperature higher than the lowest additional coolant temperature in the second heat-exchanging zone, wherein the second coolant is part of the third coolant. Additional coolant may have the same composition as the coolant evaporated in the coolest heat-exchanging zone but under another pressure or may have different composition.

EFFECT: increased output and limited size of compression and heat-exchanging equipment.

13 cl, 5 dwg, 1 ex