NATURAL GAS LIQUEFACTION METHOD Russian patent published in 2005 - IPC

FIELD: cryogenic engineering.

SUBSTANCE: invention relates to process of liquefaction of natural gas for automobile gas-filling compressor. According to proposed method, natural gas from mean pressure mains at pressure of (p≤7.6 MPa) is compressed in high-pressure of p≤25 MPa and then is successively cooled in first and second recuperative heat exchangers, throttled and delivered into service storage where gas is separated into liquid and gaseous phases. Gaseous phase is returned to compressor inlet through second and first heat exchangers. Gas of high pressure, (p≤25 MPa), additionally cooled in first heat exchanger by cold flow from preliminary cooling circuit in which at least one stage is used as additional refrigerating source. Said stage consists of recuperative heat exchanger and vortex tubes operating on high pressure gas,(p≤7.5 MPa)getting from inlet of gas-distributing station. "Cold" flow of first vortex tube is fed to mean pressure line of heat exchanger of preliminary cooling circuit. High pressure gas,(p≤7.5 MPa), cooled in said heat exchanger is supplied to inlet of second vortex tube, its "cold" flow is mixed with reverse flow of gas non-liquefied in cycle from outlet 0f second heat exchanger and is directed to inlet of mean pressure line(p≤1.6 MPa) of first heat exchanger where direct flow of high pressure gas(p≤25 MPa) is cooled to temperature T<245 K) and then gets into second and following recuperative heat exchangers. "Hot" flows of vortex tubes are united and directed into outlet mains of gas-distributing station.

EFFECT: improved reliability and reduced cost of process of liquefaction.

4 cl, 4 dwg