Butadiene extraction process

Patent metadata

Field	Value
Publication number	US-10118876-B2
Application number	US-201615230817-A
Country	US
Kind code	B2
Filing date	Aug 8, 2016
Priority date	Oct 4, 2012
Publication date	Nov 6, 2018
Grant date	Nov 6, 2018

Abstract

A process for recovering butadiene from a C 4 fraction is disclosed. The process may include: contacting a mixed C 4 stream comprising butane, butene, and butadiene, with a solvent comprising an organic solvent and water in a butadiene pre-absorber column to recover an overheads fraction comprising at least a portion of the butane, butene, and water, and a first bottoms fraction comprising the organic solvent, butadiene, and at least a portion of the butene; and feeding the first bottoms fraction to a butadiene extraction unit to recover a butene fraction, a crude butadiene fraction, and a solvent fraction.

First claim

What is claimed:

1. A system for recovering 1,3-butadiene from a C 4 fraction, comprising:
a feed line for providing a hydrocarbon fraction containing butanes, butenes, 1,2-butadiene, 1,3-butadiene, C 4 acetylenes, C 3 acetylenes, and C 5+ 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 C 3 acetylene fraction, a C 4 acetylene fraction, one or more fractions comprising the butanes and butenes, and a fraction comprising 1,2-butadiene and the C 5+ hydrocarbons;
a reactor for receiving and selectively hydrogenating at least one of the C 3 acetylene fraction and the C 4 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 C 5+ hydrocarbons and to recover a heavies fraction comprising the C 5+ hydrocarbons 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.

2. The system of claim 1 , wherein the C 4 acetylene fraction comprises C 4 acetylenes and 1,2-butadiene.

3. The system of claim 2 , further comprising a flow line for feeding the C 4 acetylene fraction to the reactor for selectively hydrogenating.

4. The system of claim 1 , wherein the butadiene extraction unit is further configured to recover a vinylcyclohexene fraction.

5. The system of claim 1 , further comprising a vaporization system for vaporizing a portion of the hydrocarbon fraction to produce a vapor fraction a liquid fraction.

6. The system of claim 1 , wherein the butadiene extraction unit comprises one or more of the following:
a pre-absorber;
a pre-fractionation column;
a feed scrubber/stripper system
a main wash column;
a rectifier;
an afterwash column;
an acetylene fractionator;
a butadiene fractionator;
an acetylene washer;
a solvent purification system; or
a degasser and cooling column.

7. A system for recovering 1,3-butadiene from a C 4 fraction, comprising:
a vaporization system for receiving a hydrocarbon fraction containing butanes, butenes, 1,2-butadiene, 1,3-butadiene, C 4 acetylenes, C 3 acetylenes, and C 5+ 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 C 3 acetylene fraction, a C 4 acetylene fraction, one or more fractions comprising the butanes and butenes, and a fraction comprising the 1,2-butadiene and the C 5+ hydrocarbons;
a reactor for receiving and selectively hydrogenating at least one of the C 3 acetylene fraction and the C 4 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 C 5+ hydrocarbons and to recover a heavies fraction comprising the C 5+ 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.

8. The system of claim 7 , wherein the butadiene extraction unit is further configured to recover a vinylcyclohexene fraction.

9. A system for recovering 1,3-butadiene from a C 4 fraction, comprising:
a feed line for providing a hydrocarbon fraction containing butanes, butenes, 1,2-butadiene, 1,3-butadiene, C 4 acetylenes, C 3 acetylenes, and C 5+ 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 C 3 acetylene fraction, a C 4 acetylene fraction, one or more fractions comprising the butanes and butenes, and a fraction comprising 1,2-butadiene and the C 5+ hydrocarbons;
a reactor for selectively hydrogenating at least one of the C 3 acetylene fraction and the C 4 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 C 5+ hydrocarbons and to recover a heavies fraction comprising the C 5+ 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.

10. The system of claim 9 , wherein the C 4 acetylene fraction comprises C 4 acetylenes and 1,2-butadiene, the system further comprising a flow line for feeding the C 4 acetylene fraction to the reactor for selectively hydrogenating.

11. The system of claim 9 , wherein the butadiene extraction unit is further configured to recover a vinylcyclohexene fraction, the system further comprising a flow line for feeding the vinylcyclohexene fraction to the separator, configured to recover the vinylcyclohexene in the heavies fraction.

12. A system for recovering 1,3-butadiene from a C 4 fraction, comprising:
a feed line for providing a hydrocarbon fraction containing butanes, butenes, 1,2-butadiene, 1,3-butadiene, C 4 acetylenes, C 3 acetylenes, and C 5+ 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 C 3 acetylene fraction, a C 4 acetylene fraction, one or more fractions comprising the butanes and butenes, a vinylcyclohexene fraction, and a fraction comprising 1,2-butadiene and the C 5+ hydrocarbons;
a reactor for selectively hydrogenating at least one of the C 3 acetylene fraction and the C 4 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 C 5+ hydrocarbons and to recover a heavies fraction, comprising the C 5+ 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.

13. A system for recovering 1,3-butadiene from a C 4 fraction, comprising:
a feed line for providing a hydrocarbon fraction containing butanes, butenes, 1,2-butadiene, 1,3-butadiene, C 4 acetylenes, C 3 acetylenes, and C 5+ 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 C 3 acetylene fraction, a C 4 acetylene fraction, one or more fractions comprising the butanes and butenes, and a fraction comprising 1,2-butadiene and the C 5+ hydrocarbons;
a reactor for selectively hydrogenating at least one of the C 3 acetylene fraction and the C 4 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 C 5+ hydrocarbons and to recover a heavies fraction comprising the C 5+ 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

Assignees

• Lummus Technology Inc

Inventors

• Brummer Robert John
• Schwint Kevin John
• Dwyer Thomas Alexander

Classifications

• B01D11/0492

  Applications, solvents used · CPC title

• C07C7/005 Primary

  Processes comprising at least two steps in series · CPC title

• B01D1/30

  Accessories for evaporators {; Constructional details thereof} · CPC title

• C07C7/167

  for removal of compounds containing a triple carbon-to-carbon bond · CPC title

• C07C5/09

  to carbon-to-carbon double bonds · CPC title