PARTIAL LIQUEFACTION OF NATURAL GAS (VERSIONS) Russian patent published in 2014 - IPC F25J1/00 

FIELD: oil-and-gas industry.

SUBSTANCE: set of invention relates to liquefaction of high-pressure natural gases and mixes thereof. In compliance with this method, cooled straight gas flow is throttled to divide it into production and process flows. Production flow is cooled, throttled and fed to fractionator to get liquid and vapour fractions. Vapour fraction is fed for recondensation with subsequent fed of a portion of recondensed production flow to fractionator as a reflux irrigation. Another portion of recondensed production flow is throttled and divided into liquid phase, a finished product, and vapour phase to be directed as a return flow for cooling of straight flow. Pre-cooled process flow is throttled, evaporated by production flow recondensation and, after repeated throttling, directed to return flow. Invention covers also a version of natural gas partial liquefaction.

EFFECT: low content of high-boiling components including carbon dioxide, enhanced performances, lower costs.

6 cl, 6 dwg