SYSTEM AND METHOD FOR SEPARATING METHANE AND NITROGEN WITH DIFFERENT VERSIONS Russian patent published in 2019 - IPC F25J3/02 

FIELD: gas industry.

SUBSTANCE: invention relates to gas separation. System for nitrogen removal and production of high pressure methane product stream comprises first divider, in which first supplied flow is divided into second and third supplied flows, First fractioning column, in which second and third supplied streams are separated into first head flow and first still flow, and second fractionating column with condenser and reboiler, in which first head flow is divided into second head flow and second still flow. System also comprises a first heat exchanger for cooling the first feed stream upstream of the first divider and for cooling the second feed stream upstream of the first fractionator by heat exchange with the first still flow and a first head flow and an external reboiler for cooling the third feed stream upstream of the first fractionator via heat exchange with the first still flow. Methane product stream contains the first and second still flows. Condenser load and reboiler load for the second fractionator are independent from each other.

EFFECT: technical result is reduction of power consumption.

18 cl, 14 dwg, 9 tbl