Production of dihydrogen by conversion of overhead gases resulting from a synthesis

Patent metadata

Field	Value
Publication number	US-9982352-B2
Application number	US-201314394023-A
Country	US
Kind code	B2
Filing date	Mar 7, 2013
Priority date	Apr 13, 2012
Publication date	May 29, 2018
Grant date	May 29, 2018

Abstract

A chemical conversion process includes a synthesis step ( 10 ) that takes, as input, reactants that include at least dihydrogen and carbon monoxide and that gives, as output, a synthetic compound such as an engine fuel, water and overhead gases, a step of recovering all or some of the overhead gases resulting from the synthesis step and a step of producing dihydrogen, in particular electrochemically ( 14 ), by a conversion of the overhead gases recovered in the recovering step.

First claim

The invention claimed is:

1. Chemical conversion process comprising:
a synthesis step that takes, as input, reactants that include at least dihydrogen and carbon monoxide and that gives, as output, a synthetic compound, water and overhead gases,
a step of recovering all or some of the overhead gases resulting from the synthesis step, and
a step of electrochemically producing dihydrogen by an assisted electrolysis which comprises electricity consumption, the assisted electrolysis including a conversion of C c H h O o compounds satisfying C+h/4−o/2>0 contained in the overhead gases recovered in the recovering step, electrochemically and in a manner that creates said dihydrogen.

2. Conversion process according to claim 1 , comprising a step of transferring the dihydrogen formed in the dihydrogen producing step to an inlet of a synthesis reactor that carries out the synthesis step.

3. Conversion process according to claim 2 , comprising a step of cracking the overhead gases resulting from the synthesis step.

4. Conversion process according to claim 2 , wherein the assisted electrolysis is on the anode side of an electrochemical device, by the overhead gases recovered in the recovering step.

5. Conversion process according to claim 1 , comprising a step of cracking the overhead gases resulting from the synthesis step.

6. Conversion process according to claim 1 , wherein the assisted electrolysis is on the anode side of an electrochemical device, by the overhead gases recovered in the recovering step.

7. Conversion process according to claim 6 , comprising a step of receiving all or some of the water resulting from the synthesis step, the assisted electrolysis step using water recovered in the receiving step.

8. Conversion process according to claim 7 , wherein fuel products are converted so as to form, at the end of the synthesis step, at least one synthetic compound consisting of a liquid engine fuel, and wherein the process comprises a step of electrolysis of water, using the fraction of water resulting from the synthesis step and not recovered during the water receiving step.

9. Conversion process according to claim 8 , comprising a step of transferring dihydrogen produced during the water electrolysis step to an inlet of the synthesis reactor that carries out the synthesis step and/or a step of transferring dioxygen produced during the water electrolysis step to an inlet of the gasification reactor that carries out the gasification step to form an oxidizing compound during the gasification step.

10. Conversion process according to claim 6 , wherein the electrolysis carried out in the assisted electrolysis is of anionic type and carries out:
a reduction reaction from water, on the cathode side of the electrochemical device, producing on the one hand some dihydrogen that constitutes the dihydrogen formed in the dihydrogen producing step, and on the other hand oxygen,
a combustion reaction on the anode side, between the oxygen resulting from the reduction reaction and the overhead gases recovered in the recovering step, in order to produce water and carbon dioxide.

11. Conversion process according to claim 10 , wherein the cracking step is applied to the gases recovered in the recovering step using steam formed from the water recovered in the receiving step and/or a reused fraction of the total amount of water resulting from the assisted electrolysis.

12. Conversion process according to claim 10 , comprising a step of collecting carbon dioxide produced during the combustion reaction at the anode.

13. Conversion process according to claim 6 , wherein the electrolysis carried out in the assisted electrolysis is of protonic type and carries out:
an oxidation reaction on the anode side, from water and gases recovered during the recovering step, producing carbon dioxide,
a reduction reaction on the cathode side of the electrochemical device, in order to create some dihydrogen that constitutes the dihydrogen formed in the dihydrogen producing step.

14. Conversion process according to claim 1 , comprising a step of heat exchange between fluids selected from the following list: overhead gases recovered during the recovering step, dihydrogen and/or water and/or carbon dioxide and/or dinitrogen resulting from the assisted electrolysis, gases resulting from the cracking step, water recovered during the receiving step and carbon dioxide recovered during the collection step.

15. Conversion process according to claim 1 , in which fuel products are converted so as to form, at the end of the synthesis step, at least one synthetic compound consisting of a liquid engine fuel.

16. Conversion process according to claim 15 , comprising a gasification step, in a gasification reactor, that takes, as input, at least said fuel products and that gives, as output, reactants that include at least one portion of the dihydrogen and of the carbon monoxide used during the synthesis step.

17. Conversion process according to claim 16 , comprising a step of transferring the carbon dioxide recovered during the carbon dioxide collection step to an inlet of the gasification reactor in order to form a carrier gas during the gasification step.

18. Conversion process according to claim 15 , comprising a step of recycling the fraction of overhead gas resulting from the synthesis step and not recovered during the overhead gas recovering step.

19. Non-transitory computer readable medium carrying a computer program comprising a computer program code suitable for the implementation of the steps of a process, when the program is executed by a computer,
wherein the implemented process is a conversion process comprising:
a synthesis step that takes, as input, reactants that include at least dihydrogen and carbon monoxide and that gives, as output, a synthetic compound, water and overhead gases,
a step of recovering all or some of the overhead gases resulting from the synthesis step, and
a step of electrochemically producing dihydrogen by an assisted electrolysis which comprises electricity consumption, the assisted electrolysis including a conversion of C c H h O o compounds satisfying C+h/4−o/2>0 contained in the overhead gases recovered in the recovering step, electrochemically and in a manner that creates said dihydrogen.

20. Chemical conversion plant comprising the computer readable medium according to claim 19 , a computer, and chemical conversion equipment, wherein the chemical conversion equipment is configured to implement the conversion process when the program carried by the computer readable medium is executed by the computer.

Assignees

• Commissariat Energie Atomique

Inventors

• Bernical Quentin

Classifications

• C25B1/02 Primary

  Hydrogen or oxygen · CPC title

• C01B3/32

  by reaction of gaseous or liquid organic compounds with gasifying agents, e.g. water, carbon dioxide or air · CPC title

• C01B2203/025

  containing a partial oxidation step · CPC title

• C01B3/36

  using oxygen; using mixtures containing oxygen as gasifying agents · CPC title

• C01B2203/0205

  containing a reforming step · CPC title