FIELD: gas industry.
SUBSTANCE: invention relates to method and system for extracting helium from natural gas in a high pressure process. Method includes steps of, passing a stream of compressed high pressure natural gas through a cooling chamber for condensation of at least part of stream of compressed natural gas to produce a cooled stream, feeding cooled stream into a cryogenic distillation column, extracting helium raw product from upper part of cryogenic distillation column and extracting a stream of liquid product from lower part of cryogenic distillation column. Temperature in cooling chamber is controlled by flash evaporation of first part of liquid product stream in cooling chamber to form a first stream of throttling gas at first pressure and flash evaporation of second part of liquid product stream into cooling chamber to form a second stream of throttling gas at pressure, that is higher than first pressure, and temperature in cooling chamber is controlled by controlling ratio of first part to second part. Wherein flash evaporation is performed by means of Joule-Thomson valve.
EFFECT: technical result is producing helium with high concentration.
20 cl, 7 dwg, 3 tbl, 3 ex
