Processes for regenerating sorbents, and associated systems

Patent metadata

Field	Value
Publication number	US-11577223-B2
Application number	US-202017090146-A
Country	US
Kind code	B2
Filing date	Nov 5, 2020
Priority date	Nov 7, 2019
Publication date	Feb 14, 2023
Grant date	Feb 14, 2023

Abstract

Processes for regenerating sorbents at high temperatures, and associated systems, are generally described.

First claim

What is claimed is:

1. A method, comprising:
regenerating a sorbent that has been exposed to an acid gas comprising carbon dioxide (CO 2 ), sulfur trioxide (SO 3 ), sulfur dioxide (SO 2 ), nitrogen dioxide (NO 2 ), and/or nitric oxide (NO) via exposure to steam such that at least part of the carbon dioxide (CO 2 ), sulfur trioxide (SO 3 ), sulfur dioxide (SO 2 ), nitrogen dioxide (NO 2 ), and/or nitric oxide (NO) is separated from the sorbent, wherein the steam is chemically inert with the sorbent and wherein the sorbent is in molten and/or solid form.

2. The method of claim 1 , wherein the sorbent is in molten form.

3. The method of claim 1 , wherein regenerating the sorbent comprises removing at least two of carbon dioxide (CO 2 ), sulfur trioxide (SO 3 ), sulfur dioxide (SO 2 ), nitrogen dioxide (NO 2 ), and nitric oxide (NO) present in the sorbent.

4. The method of claim 1 , wherein at least 1 wt % of the sorbent is regenerated.

5. The method of claim 1 , wherein at least 1 mol % of the carbon dioxide (CO 2 ), sulfur trioxide (SO 3 ), sulfur dioxide (SO 2 ), nitrogen dioxide (NO 2 ), and/or nitric oxide (NO) is released from the sorbent during regeneration.

6. The method of claim 1 , wherein an environment in which the sorbent was exposed to the acid gas is at the same temperature as the environment in which the sorbent is regenerated.

7. The method of claim 1 , wherein an environment in which the sorbent is exposed to the steam is at a temperature of above 200° C.

8. The method of claim 1 , wherein the pressure in an environment in which the sorbent is exposed to the steam is at least 1 bar.

9. The method of claim 1 , wherein the pressure in an environment in which the sorbent is exposed to the steam is at least 1.1 bar.

10. The method of claim 1 , wherein a molar ratio of steam to sorbent is at least 0.1.

11. The method of claim 1 , wherein a molar ratio of steam to acid gas in the sorbent is at least 1.

12. The method of claim 1 , wherein an environment in which the sorbent is exposed to the steam is part of an industrial process.

13. The method of claim 1 , wherein the regenerating forms a mixture of the steam and the carbon dioxide (CO 2 ), sulfur trioxide (SO 3 ), sulfur dioxide (SO 2 ), nitrogen dioxide (NO 2 ), and/or nitric oxide (NO), and further comprising subsequently cooling the mixture such that condensed steam is separated from the carbon dioxide (CO 2 ), sulfur trioxide (SO 3 ), sulfur dioxide (SO 2 ), nitrogen dioxide (NO 2 ), and/or nitric oxide (NO).

14. The method of claim 1 , wherein the carbon dioxide (CO 2 ), sulfur trioxide (SO 3 ), sulfur dioxide (SO 2 ), nitrogen dioxide (NO 2 ), and/or nitric oxide (NO) is recovered at a purity of greater than 50 wt %.

15. The method of claim 13 , wherein the steam and the carbon dioxide (CO 2 ), sulfur trioxide (SO 3 ), sulfur dioxide (SO 2 ), nitrogen dioxide (NO 2 ), and/or nitric oxide (NO) is cooled in a heat exchanger to generate energy, prior to the condensation of the steam.

16. The method of claim 13 , wherein the condensed steam is heated and recycled back into an environment in which the regeneration is performed.

17. The method of claim 1 , wherein steam quality is maintained, at least in part, by an energy source internal to a process that generates the carbon dioxide (CO 2 ), sulfur trioxide (SO 3 ), sulfur dioxide (SO 2 ), nitrogen dioxide (NO 2 ), and/or nitric oxide (NO).

18. The method of claim 1 , wherein steam quality is maintained, at least in part, by the energy content of fuel within a process that generates the carbon dioxide (CO 2 ), sulfur trioxide (SO 3 ), sulfur dioxide (SO 2 ), nitrogen dioxide (NO 2 ), and/or nitric oxide (NO).

19. The method of claim 1 , wherein steam quality is maintained, at least in part, by an energy source external to a process that generates the carbon dioxide (CO 2 ), sulfur trioxide (SO 3 ), sulfur dioxide (SO 2 ), nitrogen dioxide (NO 2 ), and/or nitric oxide (NO).

20. The method of claim 1 , wherein steam quality is maintained, at least in part, by a steam cycle powered by a process separate from a process that generates the carbon dioxide (CO 2 ), sulfur trioxide (803), sulfur dioxide (SO 2 ), nitrogen dioxide (NO 2 ), and/or nitric oxide (NO).

21. The method of claim 1 , wherein the regenerating further comprises reducing a partial pressure of the carbon dioxide (CO 2 ), sulfur trioxide (SO 3 ), sulfur dioxide (SO 2 ), nitrogen dioxide (NO 2 ), and/or nitric oxide (NO) in an environment around the sorbent.

22. The method of claim 1 , wherein a temperature of an environment in which the sorbent is exposed to the acid gas is within 200° C. of a temperature of an environment in which the sorbent is regenerated.

23. The method of claim 1 , wherein the acid gas comprises carbon dioxide.

24. The method of claim 1 , wherein the sorbent comprises an alkali metal borate.

25. A method, comprising:
regenerating a sorbent comprising an alkali metal borate in molten and/or solid form that has been exposed to an acid gas comprising carbon dioxide (CO 2 ), sulfur trioxide (SO 3 ), sulfur dioxide (SO 2 ), nitrogen dioxide (NO 2 ), and/or nitric oxide (NO) via exposure to steam such that at least part of the carbon dioxide (CO 2 ), sulfur trioxide (SO 3 ), sulfur dioxide (SO 2 ), nitrogen dioxide (NO 2 ), and/or nitric oxide (NO) is separated from the sorbent.

Assignees

• Massachusetts Inst Technology

Inventors

• Hatton Trevor Alan
• Harada Takuya
• Halliday Cameron G

Classifications

• B01J20/3491 Primary

  by pressure treatment · CPC title

• B01D2251/304

  of sodium · CPC title

• B01J20/3433

  of sorbents or filter aids other than those covered by B01J20/3408 - B01J20/3425 · CPC title

• B01D2257/504

  Carbon dioxide · CPC title

• B01J20/3483

  by thermal treatment not covered by groups B01J20/3441 - B01J20/3475, e.g. by heating or cooling · CPC title