Method and apparatus in a cryogenic liquefaction process

摘要

Methods and apparatus for the efficient cooling within air liquefaction processes with integrated use of cold recovery from an adjacent LNG gasification process are disclosed. A cryogenic liquefaction device comprises: a first heat exchanger 100; a phase separator 2; an expansion device 1; a first arrangement of conduits, arranged such that a pressurised stream of gas 31 is directed through the first heat exchanger, the expansion device and the phase separator; a cold recovery circuit including first a heat transfer fluid and a second arrangement of conduits arranged such that the first heat transfer fluid is directed through the first heat exchanger in a counter-flow direction to the pressurised stream of gas; and an refrigerant circuit 140 including a second heat transfer fluid and a third arrangement of conduits arranged such that the second heat transfer fluid is directed through the first heat exchanger in a counter-flow direction to the pressurised stream of gas; wherein: each of the second and third arrangements of conduits forms a closed pressurised circuit. Also disclosed is a method for balancing a liquefaction process using such a device.