METHOD FOR SEPARATING RAW MATERIAL GAS MIXTURE

摘要

PROBLEM TO BE SOLVED: To provide a method for recovering C2 and C3 hydrocarbons, in particular, ethylene and propylene, from a gas mixture containing C2 and C3 hydrocarbons and components lighter than them sent from an oil refinery or a petrochemical plant. SOLUTION: Cold needed by heat exchangers 115, 121 for cooling a raw material and for recovery cooling is supplied through a closed loop gas expander cooling processing cycle which preferably employs nitrogen as recirculating refrigerant. Cooling and separation for recovery can be performed by a dephlegmator 125.