Method and device for generating an alkene

Patent metadata

Field	Value
Publication number	US-9643901-B2
Application number	US-201414334146-A
Country	US
Kind code	B2
Filing date	Jul 17, 2014
Priority date	Jul 18, 2013
Publication date	May 9, 2017
Grant date	May 9, 2017

Abstract

The invention relates to a method for generating an alkene, in which a hydrocarbon-comprising feed material is subjected to a dehydrogenation and a product material comprising at least one alkene is generated. A gas stream coming from an adsorber is cooled by a gas stream which comprises the feed material, and the gas stream coming from the adsorber is cooled by a condensed component of the gas stream coming from the adsorber in a first cooling phase. Feed material is cooled in a second cooling phase by a condensed component of the gas stream coming from the adsorber. The flow of the condensed component of the gas stream coming from the adsorber, fed to the first and/or second cooling phase, is varied depending on the temperature of the gas stream leaving the first cooling phase which comprises the feed material and which is fed to the dehydrogenation.

First claim

The invention claimed is:

1. A method for generating an alkene comprising:
cooling a hydrocarbon-comprising feed stream in a cooling appliance, and then heating said hydrocarbon-comprising feed stream in a further cooling appliance,
thereafter subjecting said hydrocarbon-comprising feed stream to dehydrogenation to generate at least one alkene,
removing a gas stream from said dehydrogenation and sending said gas stream from said dehydrogenation to an adsorber,
removing a gas stream from said adsorber and sending said gas stream from said adsorber to said further cooling appliance wherein said gas stream from said adsorber is cooled by said hydrocarbon-comprising feed stream,
removing a cooled gas stream from said further cooling appliance, sending said cooled gas stream to a separator, and removing from said separator a stream of condensed component of said gas stream coming from said adsorber,
splitting said stream of condensed component into a first stream of condensed component and a second stream of condensed component, sending said first stream of condensed component to said cooling appliance to cool said hydrocarbon-comprising feed stream, and sending said second stream of condensed component to said further cooling appliance to cool said gas stream from said adsorber,
wherein the volumetric flows of said first and second streams of condensed component that are fed to said cooling appliance and said further cooling appliance, respectively, are varied in dependence on the temperature of said hydrocarbon-comprising feed stream leaving said further cooling appliance.

2. The method for generating an alkene according to claim 1 , wherein said feed material ( 1 ) is present as a feed material stream and is mixed with a recycled gas stream ( 4 ) to form a combined gas stream ( 13 ) which is used as the gas stream comprising feed material in said first cooling phase.

3. The method for generating an alkene according to claim 2 , wherein, in the second cooling phase, the feed material ( 1 ) is cooled by transfer of cold from the condensed component ( 12 ) of the gas stream coming from the adsorber ( 40 ) to a feed material stream.

4. The method for generating an alkene according to claim 3 , wherein transfer of cold from the gas stream ( 5 ), which comprises the feed material, to the gas stream ( 11 ) coming from the adsorber and transfer of cold from the condensed component ( 12 ) of the gas stream coming from the adsorber ( 40 ) to the gas stream ( 11 ) coming from the adsorber ( 40 ) proceeds in a first heat exchanger, and the transfer of cold from the condensed component ( 12 ) of the gas stream coming from the adsorber ( 40 ) to the feed material stream proceeds in a second heat exchanger.

5. The method for generating an alkene according to claim 1 , wherein, during the operation of said method, the first cooling phase and the second cooling phase, at least partially, are run simultaneously.

6. The method for generating an alkene according to claim 1 , wherein, downstream of the adsorber ( 40 ), at least one parameter of the material or of the volumetric stream of the gas stream ( 11 ) coming from the adsorber ( 40 ) is determined, and the at least one determined parameter is compared with a permissible limiting value range and, in the event of deviation of the at least one determined parameter from the limiting value range, at least one parameter of the material and/or of the volumetric stream of the condensed component ( 12 ) of the gas stream coming from the adsorber is varied.

7. The method for generating an alkene according to claim 1 , wherein the condensed component ( 12 ) of the gas stream coming from the adsorber ( 40 ) is stored in a storage appliance ( 20 ) and from there is fed to the first and/or second cooling phase according to refrigeration performance requirement.

8. The method for generating an alkene according to claim 1 , wherein the second cooling phase is carried out upstream of the first cooling phase.

9. The method for generating an alkene according to claim 1 , wherein hydrogen is obtained as a further product material ( 3 ) and the hydrogen generated is at least partially led into a dehydrogenation reactor ( 30 ) for stabilization of the dehydrogenation process.

10. The method for generating an alkene according to claim 1 , wherein said gas stream ( 11 ) coming from said adsorber ( 40 ) is compressed before being cooled in said first cooling phase.

11. The method for generating an alkene according to claim 10 , wherein, after being cooled in said first cooling phase, said gas stream ( 11 ) coming from said adsorber ( 40 ) is sent to a separator ( 22 ) wherein it is separated into said condensed component ( 12 ) of the gas stream coming from the adsorber ( 40 ) and an uncondensed component ( 2 ) of the gas stream coming from the adsorber ( 40 ).

12. The method for generating an alkene according to claim 11 , wherein the condensed component ( 12 ) of the gas stream coming from the adsorber ( 40 ) is stored in a storage appliance ( 20 ) and from there is fed to the first and/or second cooling phase according to refrigeration performance requirement.

13. The method for generating an alkene according to claim 12 , wherein the condensed component ( 12 ) of the gas stream coming from the adsorber ( 40 ) is fed from said storage appliance ( 20 ) to said first and second cooling phase as said first stream of a condensed component ( 12 ) and said second stream of a condensed component ( 12 ), respectively, via a pump.

14. The method for generating an alkene according to claim 13 , wherein the volumetric flow of said first stream of a condensed component ( 12 ) in said first cooling phase and the volumetric flow of said second stream of a condensed component ( 12 ) in said first cooling phase is, in each case, regulated by a control valve.

15. The method for generating an alkene according to claim 14 , wherein an open-loop and/or closed-loop control appliance ( 60 ) is used to vary the volumetric of said first and second streams of condensed component ( 12 ) in an automated manner in dependence on the temperature of the gas stream ( 5 ) comprising the feed material leaving said first cooling phase.

16. The method for generating an alkene according to claim 1 , wherein said feed material ( 1 ) is present as a feed material stream which is first cooled in said second cooling phase, and then divided into a first partial stream and a second partial stream,
said second partial stream of said feed stream is combined with a recycle stream to form a combined stream, and then cooled in a third cooling phase by an uncondensed component of the gas stream coming from the adsorber ( 40 ),
said combined stream is mixed with said first partial stream of said feed stream and the resultant mixed stream is used as the gas stream comprising feed material in said first cooling phase.

Assignees

• Linde Ag

Inventors

• Klein Bernd
• Trott Thomas

Classifications

• C07C5/333 Primary

  Catalytic processes · CPC title

• C07C5/327 Primary

  Formation of non-aromatic carbon-to-carbon double bonds only · CPC title

• B01D2256/24

  Hydrocarbons · CPC title

• B01D53/261

  by adsorption · CPC title

• C07C11/06

  Propene · CPC title