A method for preparing ethylene, including: passing a feed stream containing C1 and C2 hydrocarbon compounds through a first heat exchanger and feeding the feed stream passed through the first heat exchanger to a second gas-liquid separator; feeding a part of a bottom discharge stream of the second gas-liquid separator to a demethanizer, passing an overhead discharge stream of the second gas-liquid separator through a second heat exchanger, feeding the overhead discharge stream of the second gas-liquid separator passed through the second heat exchanger to a third gas-liquid separator; feeding a bottom discharge stream of the third gas-liquid separator to the demethanizer; feeding a bottom discharge stream of the demethanizer to a C2 separator; feeding an overhead discharge stream of the C2 separator to a second compressor; passing a part of a compressed discharge stream of the second compressor through the first heat exchanger and feeding the part of the compressed discharge stream of the second compressor passed through the first heat exchanger to the second compressor as a first circulation flow; passing a part of the compressed discharge stream of the second compressor through the second heat exchanger and feeding the part of the compressed discharge stream of the second compressor passed through the second heat exchanger to a first compressor as a second circulation flow; and feeding a compressed discharge stream of the first compressor to the second compressor, and an apparatus for preparing ethylene for implementing the same.

A method for preparing ethylene, including: passing a feed stream containing C1 and C2 hydrocarbon compounds through a first heat exchanger and feeding the feed stream passed through the first heat exchanger to a second gas-liquid separator; feeding a part of a bottom discharge stream of the second gas-liquid separator to a demethanizer, passing an overhead discharge stream of the second gas-liquid separator through a second heat exchanger, feeding the overhead discharge stream of the second gas-liquid separator passed through the second heat exchanger to a third gas-liquid separator; feeding a bottom discharge stream of the third gas-liquid separator to the demethanizer; feeding a bottom discharge stream of the demethanizer to a C2 separator; feeding an overhead discharge stream of the C2 separator to a second compressor; passing a part of a compressed discharge stream of the second compressor through the first heat exchanger and feeding the part of the compressed discharge stream of the second compressor passed through the first heat exchanger to the second compressor as a first circulation flow; passing a part of the compressed discharge stream of the second compressor through the second heat exchanger and feeding the part of the compressed discharge stream of the second compressor passed through the second heat exchanger to a first compressor as a second circulation flow; and feeding a compressed discharge stream of the first compressor to the second compressor, and an apparatus for preparing ethylene for implementing the same.

A method for preparing ethylene, including: passing a feed stream containing C1 and C2 hydrocarbon compounds through a first heat exchanger and feeding the feed stream passed through the first heat exchanger to a second gas-liquid separator; feeding a part of a bottom discharge stream of the second gas-liquid separator to a demethanizer, passing an overhead discharge stream of the second gas-liquid separator through a second heat exchanger, feeding the overhead discharge stream of the second gas-liquid separator passed through the second heat exchanger to a third gas-liquid separator; feeding a bottom discharge stream of the third gas-liquid separator to the demethanizer; feeding a bottom discharge stream of the demethanizer to a C2 separator; feeding an overhead discharge stream of the C2 separator to a second compressor; passing a part of a compressed discharge stream of the second compressor through the first heat exchanger and feeding the part of the compressed discharge stream of the second compressor passed through the first heat exchanger to the second compressor as a first circulation flow; passing a part of the compressed discharge stream of the second compressor through the second heat exchanger and feeding the part of the compressed discharge stream of the second compressor passed through the second heat exchanger to a first compressor as a second circulation flow; and feeding a compressed discharge stream of the first compressor to the second compressor, and an apparatus for preparing ethylene for implementing the same.

A C3 hydrocarbon fractionation system includes: a) a unit for providing a feed containing mainly propane and propylene, b) a C3 fractionation column for separating the feed to provide a top product richer in propylene than the feed and a bottom product leaner in propylene than the feed, wherein the bottom product comprises at least 50 wt % of propylene and c) a cumene production unit comprising an alkylation reactor for producing cumene from a propylene feed and a benzene feed, wherein the propylene feed comprises the bottom product of the C3 fractionation column.

A C3 hydrocarbon fractionation system includes: a) a unit for providing a feed containing mainly propane and propylene, b) a C3 fractionation column for separating the feed to provide a top product richer in propylene than the feed and a bottom product leaner in propylene than the feed, wherein the bottom product comprises at least 50 wt % of propylene and c) a cumene production unit comprising an alkylation reactor for producing cumene from a propylene feed and a benzene feed, wherein the propylene feed comprises the bottom product of the C3 fractionation column.

A process for separating a component mixture comprising essentially hydrocarbons having two or two or more carbon atoms, methane and hydrogen using a distillation apparatus (10) is proposed. Fluid (a, c, e, g, i) from the component mixture is cooled stepwise to a first pressure level, with separation of first condensates (b, d, f, h, j) out of the fluid (a, c, e, g, i) in each case. Fluid (k) from the component mixture that remains in gaseous form thereafter is expanded to a second pressure level in an expander, giving a second condensate (l). Fluid from the first condensates (b, d, f, h, j) is expanded from the first pressure level to the second pressure level and fed together with the fluid from the second condensates into the distillation apparatus (10) which is being operated at the second pressure level. The present invention likewise provides a corresponding separation apparatus.

A process for separating a component mixture comprising essentially hydrocarbons having two or two or more carbon atoms, methane and hydrogen using a distillation apparatus (10) is proposed. Fluid (a, c, e, g, i) from the component mixture is cooled stepwise to a first pressure level, with separation of first condensates (b, d, f, h, j) out of the fluid (a, c, e, g, i) in each case. Fluid (k) from the component mixture that remains in gaseous form thereafter is expanded to a second pressure level in an expander, giving a second condensate (l). Fluid from the first condensates (b, d, f, h, j) is expanded from the first pressure level to the second pressure level and fed together with the fluid from the second condensates into the distillation apparatus (10) which is being operated at the second pressure level. The present invention likewise provides a corresponding separation apparatus.

A method of recovery of rich gas where the rich gas is a hydrocarbon gas comprising less than 50 mole % methane is disclosed. The method comprises the steps of gathering the low pressure gas, compressing the gathered gas, cooling the compressed gas in a condenser so that a portion of the compressed gas condenses to form a liquefied gas and liquefied gas vapour in the condenser, and discharging the liquefied gas and liquefied gas vapour from the condenser, in which the cooling of the compressed gas is performed using at least one heat exchanger (40).

A method of recovery of rich gas where the rich gas is a hydrocarbon gas comprising less than 50 mole % methane is disclosed. The method comprises the steps of gathering the low pressure gas, compressing the gathered gas, cooling the compressed gas in a condenser so that a portion of the compressed gas condenses to form a liquefied gas and liquefied gas vapour in the condenser, and discharging the liquefied gas and liquefied gas vapour from the condenser, in which the cooling of the compressed gas is performed using at least one heat exchanger (40).

Disclosed is a method for producing hydrogen, carbon, and ethylene from a methane-containing feedstock even without recycling of unreacted methane by providing a single process or system in which a methane-containing feedstock is subjected to two methane conversion steps. The method includes a first conversion step of producing hydrogen and carbonaceous materials and a second conversion step of producing acetylene from unreacted methane and hydrogen discharged from the first conversion step while maintaining a good methane conversion and suppressing coke formation, followed by separating and recovering ethylene and hydrogen produced through selective hydrogenation of acetylene.