FIELD: gas industry.
SUBSTANCE: system and method for removing nitrogen and producing a high-pressure methane product stream and NGL product stream from natural gas feed streams are proposed, where at least 90% of ethane and preferably at least 95% of ethane in the feed stream are extracted into NGL product stream. The system and method of the invention are particularly suitable for use with supply flows over 5 million cubic feet/day (0.1 million m3/day) and up to 300 million cubic feet/day (8.5 million m3/day) and containing from about 5% to 80% of nitrogen. The system and method preferably combine the use of strategic heat exchange between various technological flows with a high-pressure distillation column and a capability of diverting all or part of the supply flow to a nitrogen removal plant with an optional bypass of a nitrogen fractionation column to reduce capital costs and operating costs.
EFFECT: removing nitrogen and producing a high-pressure methane product stream and NGL product stream from natural gas feed streams.
63 cl, 5 dwg, 2 tbl
