FIELD: gas processing industry.
SUBSTANCE: invention relates to additional maximum full extraction of valuable components from natural gas and can be used in gas-processing industry. Method for complex processing of natural hydrocarbon gas with high nitrogen content is carried out in three units: in extraction of ethane and NGL from hydrocarbon gas, where purified and dried natural gas is separated into methane fraction of high and intermediate pressure, ethane fraction, wide fraction of light hydrocarbons and methane-nitrogen mixture; in removal of nitrogen and separation of helium concentrate from methane-nitrogen mixture, where methane-nitrogen mixture is separated into methane fraction of low pressure, nitrogen low and medium pressure discharged into atmosphere, liquid nitrogen is used in fine purification and liquefaction of helium, and helium concentrate, processed with extraction of helium or discharged as a commercial product; in fine purification and liquefaction of helium, where from helium concentrate is released pure helium, during formation of gaseous vent gases containing, mainly, nitrogen and discharged into atmosphere, liquid nitrogen is used as a commercial product.
EFFECT: technical result is maximum heat recovery, reduced power consumption.
17 cl, 1 dwg, 5 tbl
