A system used to recycle exhaust gas during olefin polymer production, comprising: a compression cooling mechanism (101); a hydrocarbon membrane separation mechanism (102) and a hydrogen membrane separation mechanism (103), both connected to a first outlet (202) of the compression cooling mechanism; and a deep cooling mechanism (104) connected to a first outlet (208) of the hydrogen membrane separation mechanism. A method used to recycle exhaust gas during olefin polymer production, comprising a compression cooling step, a hydrocarbon membrane separation step, a hydrogen membrane separation step and a deep cooling step.

A raw material gas vaporization system includes: a storage tank for storing raw material gas and a transfer line for transferring the raw material gas; a reforming system including a reformer for producing hydrogen by reacting the raw material gas with water, a burner for applying heat to the reformer, and Pressure Swing Adsorption (PSA) for separating the hydrogen in the mixed gas generated from the reformer; a CO.sub.2 separation device for receiving off-gas in which the hydrogen has been removed in the mixed gas from the PSA to remove by liquefying CO.sub.2 by exchanging heat with the transfer line of the raw material gas vaporization system; and a gas supply line for supplying the remaining gas in which the CO.sub.2 has been removed in the CO.sub.2 separation device to a burner as fuel.

One or more specific embodiments disclosed herein includes a method for separating hydrogen from an olefin hydrocarbon rich compressed effluent vapor stream, employing a single heat exchanger, multiple gas-liquid separators, multiple expander/compressor sets, and a rectifier attached to a liquid product drum.

One or more specific embodiments disclosed herein includes a method for separating hydrogen from an olefin hydrocarbon rich compressed effluent vapor stream, employing a single heat exchanger, multiple gas-liquid separators, multiple expander/compressor sets, and a rectifier attached to a liquid product drum.

One or more specific embodiments disclosed herein includes a method for separating hydrogen from an olefin hydrocarbon rich compressed effluent vapor stream, employing a single heat exchanger, multiple gas-liquid separators, multiple expander/compressor sets, and a rectifier attached to a liquid product drum.

This method includes introducing a downstream stream (140) of cracked gas from a downstream heat exchanger (58) in a downstream separator (60) and recovering, at the head of the downstream separator (60), a high-pressure fuel gas stream (144). The method includes the passage of the stream (144) of fuel through the downstream exchanger (58) and an intermediate exchanger (50, 54) to form a reheated high-pressure fuel stream (146), the expansion of the reheated high-pressure fuel stream (146) in at least a first dynamic expander (68) and the passage of the partially expanded fuel stream (148) from the intermediate exchanger (50, 54) in a second dynamic expander (70) to form an expanded fuel stream (152). The expanded fuel stream (152) from the second dynamic expander (70) is reheated in the downstream heat exchanger (58) and in the intermediate heat exchanger (50, 54).

One or more specific embodiments disclosed herein includes a method for separating hydrogen from an olefin hydrocarbon rich compressed effluent vapor stream, employing a single heat exchanger, multiple gas-liquid separators, multiple expander/compressor sets, and a rectifier attached to a liquid product drum.

A cryogenic technology for the cost-efficient capture of each known component of emissions, such as carbon dioxide, sulfur oxides, nitrogen oxides, carbon monoxide, any other acid vapor, mercury, steam, in a liquefied or frozen/solidified form, and unreacted nitrogen (gas) from industrial plants, such that each of the components is captured separately with minimum use of energy and is industrially useful.

One or more specific embodiments disclosed herein includes a method for separating hydrogen from an olefin hydrocarbon rich compressed effluent vapor stream, employing a single heat exchanger, multiple gas-liquid separators, multiple expander/compressor sets, and a rectifier attached to a liquid product drum.

A system for separating olefinic hydrocarbon and hydrogen in an effluent fluid stream from a dehydrogenation reactor includes a heat exchanger that receives and partially condenses the effluent fluid stream so that a mixed phase effluent stream is formed. A primary separation device receives and separates the mixed phase effluent stream into a primary vapor stream and a primary liquid product stream. A heat exchanger receives and partially condenses the primary vapor stream so that a mixed phase primary stream is formed. A secondary separation device receives and separates the mixed phase primary stream into a secondary vapor stream and a secondary liquid product stream. A heat exchanger receives and warms the secondary vapor stream to provide refrigeration for partially condensing the effluent fluid stream and a heat exchanger receives and warms the secondary vapor stream to provide refrigeration for partially condensing the primary vapor stream. A mixed refrigerant compression system provides refrigerant to a heat exchanger to provide refrigeration.