Method and system for obtaining one or more olefins

Patent metadata

Field	Value
Publication number	US-11066346-B2
Application number	US-201816603480-A
Country	US
Kind code	B2
Filing date	Apr 6, 2018
Priority date	Apr 7, 2017
Publication date	Jul 20, 2021
Grant date	Jul 20, 2021

Abstract

The invention relates to a method ( 100, 200 ) of obtaining one or more olefins, in which, using an oxidative coupling of methane ( 10 ), a gas mixture comprising hydrogen, methane, carbon monoxide and higher-boiling hydrocarbons than methane is formed and is subjected to a low-temperature separation ( 1 - 5 ), characterized in that the low-temperature separation ( 1 - 5 ) is conducted using a rectification column ( 2 ) having a first separation region ( 21 ), a second separation region ( 22 ) arranged above the first separation region ( 21 ), and a condenser-evaporator ( 23 ), wherein the gas mixture is cooled, fed at least partly as first separation feed into the first separation region ( 21 ) and subjected to a first rectification in the first separation region ( 21 ) to form a first tops gas and a first bottoms liquid, wherein, using a first proportion of the first tops gas in the condenser-evaporator ( 23 ), a condensate which is recycled to the first separation region and, using a second proportion of the tops gas, a second separation feed which is fed into the second separation region ( 22 ) are formed, and wherein the second separation feed is subjected to a second rectification in the second separation region to form a second tops gas and a second bottoms liquid.

First claim

The invention claimed is:

1. Method ( 100 , 200 ) of obtaining one or more olefins, in which, using an oxidative coupling of methane ( 10 ), a gas mixture comprising hydrogen, methane, carbon monoxide and higher-boiling hydrocarbons than methane is formed and is subjected to a low-temperature separation ( 1 - 5 ), characterized in that the low-temperature separation ( 1 - 5 ) is conducted using a rectification column ( 2 ) having a first separation region ( 21 ), a second separation region ( 22 ) arranged above the first separation region ( 21 ), and a condenser-evaporator ( 23 ), wherein the gas mixture is cooled, fed at least partly as first separation feed into the first separation region ( 21 ) and subjected to a first rectification in the first separation region ( 21 ) to form a first tops gas and a first bottoms liquid, wherein, using a first proportion of the first tops gas in the condenser-evaporator ( 23 ), a condensate which is recycled to the first separation region and, using a second proportion of the tops gas, a second separation feed which is fed into the second separation region ( 22 ) are formed, and wherein the second separation feed is subjected to a second rectification in the second separation region ( 22 ) to form a second tops gas and a second bottoms liquid.

2. Method ( 100 , 200 ) according to claim 1 , in which the cooling of the gas mixture prior to the at least partial feeding as first separation feed into the first separation region ( 21 ) is effected to a temperature level of −70 to −95° C.

3. Method ( 100 , 200 ) according to claim 1 , in which one pressure level at which the rectification column ( 2 ) is operated is 24 to 36 bar.

4. Method ( 100 , 200 ) according to claim 1 , in which, using a first proportion of the second tops gas, a condensate which is recycled to the first separation region is formed, wherein a second proportion of the second tops gas is expanded to a lower pressure level and subjected to a heat exchange with the first proportion of the second tops gas.

5. Method ( 100 , 200 ) according to claim 4 , in which the second proportion of the second tops gas, after the expansion to the lower pressure level and the heat exchange with the first proportion of the second tops gas, is compressed from the lower pressure level to a higher pressure level.

6. Method ( 100 , 200 ) according to claim 5 , in which a turboexpander ( 4 ) is used for expansion of the second proportion of the second tops gas to the lower pressure level, and a turbocompressor ( 5 ) driven by the turboexpander ( 4 ) is used for compression of the second tops gas from the lower pressure level to the higher pressure level.

7. Method according to claim 5 , in which the lower pressure level is 6 to 11 bar and the higher pressure level is 10 to 15 bar.

8. Method according to claim 5 , in which the second proportion of the second tops gas, after the expansion to the lower pressure level, after the heat exchange with the first proportion of the second tops gas, and before the compression from the lower pressure level to the higher pressure level, is subjected to heat exchange with the gas mixture which is at least partly fed into the first separation region ( 21 ) as first separation feed in order to cool it.

9. Method according to claim 1 , in which the condenser-evaporator ( 23 ) is cooled by means of ethylene coolant.

10. Method according to claim 1 , in which the condenser-evaporator ( 23 ) is cooled using at least a portion of the first bottoms liquid.

11. Plant for obtaining one or more olefins, having means set up, using an oxidative coupling of methane ( 10 ), for forming a gas mixture comprising hydrogen, methane, carbon monoxide and higher-boiling hydrocarbons than methane and subjecting it to a low-temperature separation ( 1 - 5 ), characterized in that a rectification column ( 2 ) having a first separation region ( 21 ), a second separation region ( 22 ) arranged above the first separation region ( 21 ), and a condenser-evaporator ( 23 ) is provided for the low-temperature separation ( 1 - 5 ), wherein means set up for cooling the gas mixture, for feeding it at least partly as first separation feed into the first separation region ( 21 ) and for subjecting it to a first rectification in the first separation region ( 21 ) to form a first tops gas and a first bottoms liquid, for forming a condensate using a first proportion of the first tops gas in the condenser-evaporator ( 23 ) and for recycling it to the first separation region, for forming a second separation feed using a second proportion of the first tops gas and for feeding it into the second separation region ( 22 ), and for subjecting the second separation feed to a second rectification in the second separation region to form a second tops gas and a second bottoms liquid are provided.

12. Plant according to claim 11 , in which the first separation region ( 21 ), the second separation region ( 22 ) and the condenser-evaporator ( 23 ) are disposed in a common outer shell.

13. Plant according to claim 11 , set up to conduct a method of obtaining one or more olefins, in which, using an oxidative coupling of methane ( 10 ), a gas mixture comprising hydrogen, methane, carbon monoxide and higher-boiling hydrocarbons than methane is formed and is subjected to a low-temperature separation ( 1 - 5 ), characterized in that the low-temperature separation ( 1 - 5 ) is conducted using a rectification column ( 2 ) having a first separation region ( 21 ), a second separation region ( 22 ) arranged above the first separation region ( 21 ), and a condenser-evaporator ( 23 ), wherein the gas mixture is cooled, fed at least partly as first separation feed into the first separation region ( 21 ) and subjected to a first rectification in the first separation region ( 21 ) to form a first tops gas and a first bottoms liquid, wherein, using a first proportion of the first tops gas in the condenser-evaporator ( 23 ), a condensate which is recycled to the first separation region and, using a second proportion of the tops gas, a second separation feed which is fed into the second separation region ( 22 ) are formed, and wherein the second separation feed is subjected to a second rectification in the second separation region ( 22 ) to form a second tops gas and a second bottoms liquid.

14. Method ( 100 , 200 ) according to claim 2 , in which one pressure level at which the rectification column ( 2 ) is operated is 24 to 36 bar.

15. Method ( 100 , 200 ) according to claim 2 , in which, using a first proportion of the second tops gas, a condensate which is recycled to the first separation region is formed, wherein a second proportion of the second tops gas is expanded to a lower pressure level and subjected to a heat exchange with the first proportion of the second tops gas.

16. Method ( 100 , 200 ) according to claim 3 , in which, using a first proportion of the second tops gas, a condensate which is recycled to the first separation region is formed, wherein a second proportion of the second tops gas is expanded to a lower pressure level and subjected to a heat exchange with the first proportion of the second tops gas.

17. Method according to claim 6 , in which the lower pressure level is 6 to 11 bar and the higher pressure level is 10 to 15 bar.

18. Method according to claim 6 , in which the second proportion of the second tops gas, after the expansion to the lower pressure level, after the heat exchange with the first proportion of the second tops gas, and before the compression from the lower pressure level to the higher pressur

Assignees

• Linde Ag

Inventors

• Fritz Helmut
• Ernst Christian
• Sinn Tobias

Classifications

• F25J2200/72

  Refluxing the column with at least a part of the totally condensed overhead gas · CPC title

• F25J2290/40

  Vertical layout or arrangement of cold equipments within in the cold box, e.g. columns, condensers, heat exchangers etc. · CPC title

• F25J3/0233

  separation of CnHm with 1 carbon atom or more · CPC title

• B01D3/007 Primary

  Energy recuperation; Heat pumps · CPC title

• C07C7/005 Primary

  Processes comprising at least two steps in series · CPC title