Butadiene extraction process

A system for recovering 1,3-butadiene from a C4 fraction, comprising:

• a vaporization system for receiving a hydrocarbon fraction containing butanes, butenes, 1,2-butadiene, 1,3-butadiene, C4 acetylenes, C3 acetylenes, and C5+ hydrocarbons and producing a vapor fraction and a liquid fraction;
• a butadiene unit for receiving the vapor fraction and recovering a 1,3-butadiene fraction, a C3 acetylene fraction, a C4 acetylene fraction, one or more fractions comprising the butanes and butenes, and a fraction comprising the 1,2-butadiene and the C5+ hydrocarbons;
• a reactor for receiving and selectively hydrogenating at least one of the C3 acetylene fraction and the C4 acetylene fraction to produce a hydrogenated effluent comprising olefins, dienes, and oligomer byproducts;
• a separator for receiving the hydrogenated effluent and the fraction comprising the 1,2-butadiene and the C5+ hydrocarbons and to recover a heavies fraction comprising the C5+ hydrocarbons and the oligomer byproducts and a lights fraction comprising the olefins, dienes, and 1,2-butadiene;
• a flow line for feeding the liquid fraction to the separator as a reflux;
• and
• a flow line for feeding the lights fraction to the butadiene extraction unit.

A system for recovering 1,3-butadiene from a C4 fraction, comprising:

• a feed line for providing a hydrocarbon fraction containing butanes, butenes, 1,2-butadiene, 1,3-butadiene, C4 acetylenes, C3 acetylenes, and C5+ hydrocarbons;
• a butadiene extraction unit for receiving a portion of the hydrocarbon fraction and separating the hydrocarbon fraction into a 1,3-butadiene fraction, a C3 acetylene fraction, a C4 acetylene fraction, one or more fractions comprising the butanes and butenes, and a fraction comprising 1,2-butadiene and the C5+ hydrocarbons;
• a reactor for selectively hydrogenating at least one of the C3 acetylene fraction and the C4 acetylene fraction to produce a hydrogenated effluent comprising olefins, dienes, and oligomer byproducts;
• a separator for receiving the hydrogenated effluent and the fraction comprising the 1,2-butadiene and the C5+ hydrocarbons and to recover a heavies fraction comprising the C5+ hydrocarbons and the oligomer byproducts and a lights fraction comprising the olefins, dienes, and 1,2-butadiene, wherein the separator is configured to receive a remaining portion of the hydrocarbon fraction as a reflux;
• and
• a flow line for feeding the light fraction to the butadiene extraction unit.

A system for recovering 1,3-butadiene from a C4 fraction, comprising:

• a feed line for providing a hydrocarbon fraction containing butanes, butenes, 1,2-butadiene, 1,3-butadiene, C4 acetylenes, C3 acetylenes, and C5+ hydrocarbons;
• a butadiene extraction unit for receiving at least a portion of the hydrocarbon fraction and separating the hydrocarbon fraction into a 1,3-butadiene fraction, a C3 acetylene fraction, a C4 acetylene fraction, one or more fractions comprising the butanes and butenes, a vinylcyclohexene fraction, and a fraction comprising 1,2-butadiene and the C5+ hydrocarbons;
• a reactor for selectively hydrogenating at least one of the C3 acetylene fraction and the C4 acetylene fraction to produce a hydrogenated effluent comprising olefins, dienes, and oligomer byproducts;
• a separator for receiving the hydrogenated effluent, the vinylcyclohexene fraction, and the fraction comprising the 1,2-butadiene and the C5+ hydrocarbons and to recover a heavies fraction, comprising the C5+ hydrocarbons, the vinylcyclohexene, and the oligomer byproducts, and a lights fraction, comprising the olefins, dienes, and 1,2-butadiene;
• and
• a flow line for feeding the lights fraction to the butadiene extraction unit.

A system for recovering 1,3-butadiene from a C4 fraction, comprising:

• a feed line for providing a hydrocarbon fraction containing butanes, butenes, 1,2-butadiene, 1,3-butadiene, C4 acetylenes, C3 acetylenes, and C5+ hydrocarbons;
• a butadiene extraction unit for receiving at least a portion of the hydrocarbon fraction and separating the hydrocarbon fraction into a 1,3-butadiene fraction, a C3 acetylene fraction, a C4 acetylene fraction, one or more fractions comprising the butanes and butenes, and a fraction comprising 1,2-butadiene and the C5+ hydrocarbons;
• a reactor for selectively hydrogenating at least one of the C3 acetylene fraction and the C4 acetylene fraction to produce a hydrogenated effluent comprising olefins, dienes, and oligomer byproducts;
• a separator for receiving the hydrogenated effluent and the fraction comprising the 1,2-butadiene and the C5+ hydrocarbons and to recover a heavies fraction comprising the C5+ hydrocarbons and the oligomer byproducts and a lights fraction comprising the olefins, dienes, and 1,2-butadiene;
• a flow line for feeding the lights fraction to the butadiene extraction unit;
• and
• a flow line for feeding at least a portion of the hydrocarbon fraction to the separator as a reflux.

A system for recovering 1,3-butadiene from a C4 fraction, comprising:

• a feed line for providing a hydrocarbon fraction containing butanes, butenes, 1,2-butadiene, 1,3-butadiene, C4 acetylenes, C3 acetylenes, and C5+ hydrocarbons;
• a butadiene extraction unit for receiving at least a portion of the hydrocarbon fraction and separating the hydrocarbon fraction into a 1,3-butadiene fraction, a C3 acetylene fraction, a C4 acetylene fraction, one or more fractions comprising the butanes and butenes, and a fraction comprising 1,2-butadiene and the C5+ hydrocarbons;
• a reactor for selectively hydrogenating at least one of the C3 acetylene fraction and the C4 acetylene fraction to produce a hydrogenated effluent comprising olefins, dienes, and oligomer byproducts;
• a separator for receiving the hydrogenated effluent and the fraction comprising the 1,2-butadiene and the C5+ hydrocarbons and to recover a heavies fraction comprising the C5+ hydrocarbons and the oligomer byproducts and a lights fraction comprising the olefins, dienes, and 1,2-butadiene;
• a flow line for feeding the lights fraction to the butadiene extraction unit;
• a vaporization system for vaporizing a portion of the hydrocarbon fraction to produce a vapor fraction and a liquid fraction;
• and
• a flow line for feeding the liquid fraction to the separator as a reflux.

A system for recovering 1,3-butadiene from a C4 fraction, comprising:

• a vaporization system for receiving a hydrocarbon fraction containing butanes, butenes, 1,2-butadiene, 1,3-butadiene, C4 acetylenes, C3 acetylenes, and C5+ hydrocarbons and producing a vapor fraction and a liquid fraction;
• a butadiene unit for receiving the vapor fraction and recovering a 1,3-butadiene fraction, a C3 acetylene fraction, a C4 acetylene fraction, a vinylcyclohexene fraction, one or more fractions comprising the butanes and butenes, and a fraction comprising the 1,2-butadiene and the C5+ hydrocarbons;
• a reactor for selectively hydrogenating at least one of the C3 acetylene fraction and the C4 acetylene fraction to produce a hydrogenated effluent comprising olefins, dienes, and oligomer byproducts;
• a separator for receiving the hydrogenated effluent, the vinylcyclohexene fraction, and the fraction comprising the 1,2-butadiene and the C5+ hydrocarbons and to recover a heavies fraction, comprising the C5+ hydrocarbons, the vinylcyclohexene, and the oligomer byproducts, and a lights fraction, comprising the olefins, dienes, and 1,2-butadiene;
• a flow line for feeding the liquid fraction to the separator as a reflux;
• and
• a flow line for feeding the lights fraction to the butadiene extraction unit.