Oxidative coupling of methane for olefin production

Patent metadata

Field	Value
Publication number	US-9944573-B2
Application number	US-201715487181-A
Country	US
Kind code	B2
Filing date	Apr 13, 2017
Priority date	Apr 13, 2016
Publication date	Apr 17, 2018
Grant date	Apr 17, 2018

Abstract

The present disclosure provides natural gas and petrochemical processing systems, including oxidative coupling of methane reactor systems that may integrate process inputs and outputs to cooperatively utilize different inputs and outputs in the production of higher hydrocarbons from natural gas and other hydrocarbon feedstocks. The present disclosure also provides apparatuses and methods for heat exchange, such as an apparatus that can perform boiling and steam super-heating in separate chambers in order to reach a target outlet temperature that is relatively constant as the apparatus becomes fouled. A system of the present disclosure may include an oxidative coupling of methane (OCM) subsystem that generates a product stream comprising compounds with two or more carbon atoms, and a dual compartment heat exchanger downstream of, and fluidically coupled to, the OCM subsystem.

First claim

What is claimed is:

1. A method for producing propylene, comprising:
(a) directing methane (CH 4 ) and oxygen (O 2 ) into an oxidative coupling of methane (OCM) reactor that permits the CH 4 and the O 2 to react to yield an OCM product stream comprising hydrocarbon compounds with two or more carbon atoms (C 2+ compounds), including ethylene;
(b) directing at least a portion of the OCM product stream into a separations unit that yields an ethylene stream comprising the ethylene from the OCM product stream;
(c) directing at least a portion of the ethylene stream from the separations unit into a dimerization reactor that permits at least a portion of the ethylene to react in a dimerization reaction to yield a butene stream comprising one or more butene compounds;
(d) directing at least a portion of the butene stream into a C 4 separations unit that yields a butene-2 stream comprising butene-2 from the at least a portion of the butene stream; and
(e) directing at least a portion of the butene-2 stream and at least another portion of the ethylene stream into a metathesis reactor that permits at least a portion of the butene-2 and the ethylene to react to yield a metathesis product stream comprising higher hydrocarbon compounds, including the propylene.

2. The method of claim 1 , further comprising directing at least a portion of the metathesis product stream into a C 2 separations unit that separates the at least a portion of the metathesis product stream to at least a C 2 stream comprising hydrocarbon compounds with two carbon atoms (C 2 compounds) and a C 3+ stream comprising hydrocarbon compounds with three or more carbon atoms (C 3+ compounds), including at least a portion of the propylene.

3. The method of claim 2 , further comprising directing the C 2 stream into the separations unit.

4. The method of claim 2 , further comprising directing the C 3+ stream into a C 3 separations unit that separates the C 3+ stream to at least a C 3 stream comprising propylene and a C 4+ stream comprising hydrocarbon compounds with four or more carbon atoms (C 4+ compounds).

5. The method of claim 4 , further comprising directing the C 4+ stream into the C 4 separations unit.

6. The method of claim 1 , further comprising directing the propylene from the metathesis product stream into a polypropylene unit that permits the propylene to react to yield a polypropylene product stream comprising polypropylene.

7. The method of claim 6 , further comprising directing at least a portion of the ethylene from the separations unit to the polypropylene unit, wherein the polypropylene unit reacts the at least the portion of the ethylene as a co-monomer with the propylene.

8. The method of claim 7 , wherein a molar ratio of ethylene co-monomer to total monomer and co-monomer is from about 0.01:0.99 to about 0.15:0.85.

9. The method of claim 8 , wherein the molar ratio of ethylene co-monomer to total monomer and co-monomer is from about 0.08:0.92 to about 0.15:0.85.

10. The method of claim 1 , wherein (a) further comprises directing ethane (C 2 H 6 ) into the OCM reactor.

11. The method of claim 1 , further comprising injecting olefins with five or more carbon atoms (C 5+ olefin) into one or more of the separations unit, the dimerization reactor, the C 4 separations unit, and the metathesis reactor.

12. The method of claim 1 , wherein the at least another portion of the ethylene stream is a remainder of the ethylene stream.

13. A method for producing butene-1, comprising:
(a) directing methane (CH 4 ) and oxygen (O 2 ) into an oxidative coupling of methane (OCM) reactor that permits the CH 4 and the O 2 to react to yield an OCM product stream comprising hydrocarbon compounds with two or more carbon atoms (C 2+ compounds), including ethylene;
(b) directing at least a portion of the OCM product stream into a dimerization reactor that permits at least a portion of the ethylene to react to produce a dimerization product stream comprising the butene-1; and
(c) directing the dimerization product stream into a separations unit that produces a first stream containing un-reacted ethylene and a second stream containing the butene-1.

14. A method for producing butene-2, comprising:
(a) directing methane (CH 4 ) and oxygen (O 2 ) into an oxidative coupling of methane (OCM) reactor that permits the CH 4 and the O 2 to react to yield an OCM product stream comprising hydrocarbon compounds with two or more carbon atoms (C 2+ compounds), including ethylene;
(b) directing at least a portion of the OCM product steam into a dimerization reactor that permits at least a portion of the ethylene to react to produce a dimerization product stream comprising butene-1; and
(c) directing the dimerization product stream into a hydroisomerization reactor that converts the butene-1 to the butene-2.

15. A method for performing an oxidative coupling of methane (OCM) reaction, comprising:
(a) directing a first portion of methane (CH 4 ) and a first portion of oxygen (O 2 ) into a first OCM reactor, wherein the first OCM reactor is an adiabatic reactor;
(b) in the first OCM reactor, producing a first product stream comprising hydrocarbon compounds with two or more carbon atoms (C 2+ compounds) and liberating a first portion of heat, which first portion of heat increases a temperature of the first product stream;
(c) directing a second portion of CH 4 and a second portion of oxygen O 2 into a second OCM reactor, wherein the second OCM reactor is an isothermal reactor;
(d) in the second OCM reactor, producing a second product stream comprising hydrocarbon compounds with two or more carbon atoms (C 2+ compounds) and liberating a second portion of heat, which second portion of heat is removed from the second OCM reactor; and
(e) combining the second product stream with the first product stream, wherein the first portion of heat aids in converting ethane (C 2 H 6 ) in the first and/or second product streams into ethylene (C 2 H 4 ).

16. The method of claim 13 , further comprising recycling the un-reacted ethylene to the dimerization reactor.

17. The method of claim 13 , further comprising reacting the butene-1 with the ethylene to produce low linear density polyethylene (LLDPE).

18. The method of claim 13 , wherein the dimerization reactor contains a catalyst containing titanium.

19. The method of claim 14 , further comprising directing the butene-2 and at least a portion of the ethylene to a metathesis reactor to produce propylene.

20. The method of claim 14 , further comprising recycling un-reacted ethylene to the dimerization reactor.

21. The method of claim 15 , further comprising (i) adding C 2 H 6 to the first product stream, and (ii) converting the C 2 H 6 added in (i) into C 2 H 4 .

22. The method of claim 15 , further comprising (i) adding C 2 H 6 to the combined stream in (e), and (ii) converting the C 2 H 6 added in (i) into C 2 H 4 .

23. The method of claim 15 , wherein the second OCM reactor is a tubular reactor.

24. The method of claim 15 , wherein the second OCM reactor is a fluidized bed reactor.

25. The method of claim 15 , wherein the first portion of heat increases the temperature of the first product stream to at least about 800° C.

26. The method of claim 15 , wherein the second portion of heat is removed from the second OCM reactor such that a temperature of the second product stream is less than about 800

Assignees

• Siluria Technologies Inc

Inventors

• Radaelli Guido
• Duggal Suchia
• Cizeron Joel
• Schammel Wayne
• Martens Franciscus J A

Classifications

• F28D7/16

  the conduits being arranged in parallel spaced relation ({F28D7/0008 - F28D7/0058 take precedence}; F28D7/02 - F28D7/10 take precedence) · CPC title

• C07C2/84 Primary

  catalytic · CPC title

• C08F10/02

  Ethene · CPC title

• Y02P20/52

  using catalysts, e.g. selective catalysts · CPC title

• C07C6/04

  at a carbon-to-carbon double bond · CPC title