FIELD: technological processes.
SUBSTANCE: invention relates to installations low-temperature dephlegmation with rectification and can be used in gas industry for extraction of hydrocarbons C2+ from main natural gas. Disclosed group of inventions includes installation options LTDR for deethanization of main gas with high and low pressure gas lines. At that, plant LTDR for deethanization of the main gas with high and low pressure gas lines includes a drying unit, a recuperative heat exchanger, expanders connected to the compressor by kinematic or electrical connection, a refluxer with a reflux line connected by a reflux gas feed line equipped with an expander and a low pressure gas supply line with a separator which is equipped with lines for feeding methane-containing gas from the fractionation unit and a wide fraction of light hydrocarbons into a fractionation unit, wherein the separator is a demethanizer connected to the refluxer due a reflux supply line with a reducing device, supply line of wide fraction of light hydrocarbons is connected to the second recuperative heat exchanger arranged on the bypass line of the recuperative heat exchanger after the compression refrigerating machine, wherein the wide hydrocarbon light hydrocarbon feed line is connected to the demethanizer after the second recuperative heat exchanger.
EFFECT: high output of hydrocarbons C2+ due to low temperature of high pressure gas by placing an additional recovery heat exchanger and reducing the carryover of hydrocarbons C2+ during fractionation due to installation of preliminary demethanizer in place of separator.
2 cl, 2 dwg
