Heat recovery gas absorption process

• US 20070221065A1
• Filed: 03/23/2006
• Published: 09/27/2007
• Est. Priority Date: 03/23/2006
• Status: Abandoned Application

• Current Assignee: University of Regina
• Original Assignee: University of Regina
• Inventors: Veawab, Amornvadee, Aroonwilas, Adisorn
• Application Number:
  US11/386,824
• Publication Number:
  US 20070221065A1
• Time in Patent Office: Days
• US Class Current: 96/243
• CPC Class Codes: B01D 53/14 by absorption
• CPC Class Codes: B01D 53/1456 Removing acid components
• CPC Class Codes: B01D 53/18 Absorbing units; Liquid distributors therefor B01D3/16, B01D3/26, B01D3/30 take precedence; packing elements B01J19/30, B01J19/32
• CPC Class Codes: Y10S 423/06 Temperature control
• CPC Class Codes: Y10S 423/08 Corrosion or deposition inhibiting

Abstract

Apparatus comprising an absorber device provided with a plurality of sequentially adjacent sections for flowing a gas stream therethrough. A conduit infrastructure comprising a section configured to ingress, communicate with and egress from each section of the absorber device, and a recovery and regeneration section, is configured with a plurality of heat exchange and cooling equipment. A process wherein a liquid solvent provided with at least one chemical compound selected for reacting with the selected gaseous component, is counter-flowed against and commingled with the gas stream. The liquid solvent temperature is controllably manipulated between each section of the column to provide: (a) thermodynamic-driven mass transfer at the front end of the absorber device, and (b) kinetic-driven mass transfer at the back end of the absorber device. The heat generated during the recovery of the gaseous component from the absorption liquid solvent system is recovered for use in regenerating solvent system.

Claims

1. An apparatus for removing and recovering at least one selected gaseous component from a gas stream, the apparatus comprising:

an absorber device configured with a plurality of sequentially adjacent sections for flowing a gas stream therethrough, said absorber device provided with an inlet at one end and an outlet at the opposing end for said gas stream;

a conduit infrastructure for conveying an absorption liquid solvent system configured to remove, assimilate and accumulate therein a selected gaseous component from the gas stream, said conduit infrastructure configured to communicate with each section of said absorber device to counterflow said solvent system therethrough against said gas stream, a section of said conduit infrastructure egressing from a bottom portion of each section of said absorber and ingressing into a top portion of the adjacent section of said absorber device;

a first plurality of equipment interposed each section of conduit infrastructure egressing from a bottom portion of each section and ingressing into a top portion of the adjacent section of said absorber device, said plurality of equipment configured to controllably manipulate and adjust the temperature of said absorption liquid solvent system conveyed therein said section of the conduit infrastructure; and

a second plurality of equipment configured to communicate and cooperate with the conduit infrastructure to;

(a) remove and recover the absorbed and accumulated gaseous component from the liquid solvent system, (b) regenerate the absorption liquid solvent system, (c) recycle said regenerated absorption liquid solvent system back to the absorber device, and (d) controllably manipulate and adjust the temperature of said liquid solvent system during recycling back to the absorber device.

2. The apparatus of claim 1, wherein said outlet of the absorber device communicates with a condenser for flowing the gas stream therethrough.

3. The apparatus of claim 1, wherein a phase separator is interposed said first and second pluralities of equipment.

4. The apparatus of claim 1, wherein a phase separator is provided for flowing therethrough said gaseous component recovered by said second plurality of equipment.

5. The apparatus of claim 1, wherein said conduit infrastructure is a piping infrastructure.

6. The apparatus of claim 1, wherein the absorber device comprises a multi-sectioned oriented absorption column provided with a gas inlet near the bottom of the column for receiving therethrough a gas stream, a gas outlet at the top of the column for releasing therethrough said gas stream, said column provided with a plurality of sequentially adjacent sections interposed said inlet and said outlet wherein a first section is adjacent to the gas outlet at the top of said column and a last section communicates with the gas inlet near the bottom of said column;

7. The apparatus of claim 1, wherein the first plurality of equipment is configured to controllably increase the temperature of said solvent system during conveyance therein the conduit infrastructure between the first section and a second section of the absorber device.

8. The apparatus of claim 1, wherein the first plurality of equipment is configured to controllably decrease the temperature of said solvent system during conveyance therein the conduit infrastructure between subsequent sections of the absorber device.

9. The apparatus of claim 1, wherein the first plurality of equipment comprises a heat exchange unit interposed each section of said conduit infrastructure egressing from a bottom portion of each section of said absorber and ingressing into a top portion of the adjacent section of said absorber device.

10. The apparatus of claim 8, wherein the first plurality of equipment is provided with at least one cooling unit configured to cooperate with each heat exchange unit interposed a second section and subsequent sections of said absorber device.

11. The apparatus of claim 10, wherein said cooling unit is a pinched cooling unit.

12. The apparatus of claim 1, wherein the second plurality of equipment is provided with at least one heat exchange unit configured to cooperate with the conduit infrastructure egressing from the bottom portion of a section of the absorber device and ingressing into the top portion of an adjacent section of said absorber device.

13. The apparatus of claim 1, wherein the second plurality of equipment comprises:

at least one regenerator for separating the absorption liquid solvent system containing therein said absorbed and assimilated gaseous component, into a steam stream comprising the gaseous component and a stream of partially regenerated liquid solvent system;

a reboiler unit for heating and regenerating therein said liquid solvent system;

at least one heat exchange unit for flowing therethrough said steam stream, said heat exchange unit communicating with said reboiler unit;

at least one heat exchange unit configured to controllably decrease the temperature of the regenerated solvent system; and

at least one cooling unit configured to controllably decrease the temperature of the regenerated solvent system before ingressing the absorption liquid solvent into the first section of absorber

14. A process for removing and recovering a selected gaseous component from a gas stream, the process comprising:

flowing the gas stream through an absorber device provided with a plurality of sequentially adjacent sections, said gas stream flowing from a front end to a back end of the absorber device;

commingling and contacting the gas stream therein each section of said absorber device with a counter-flowing absorption liquid solvent system thereby enriching said absorption liquid solvent system;

providing conditions;

(a) at the front end of said absorber device for thermodynamic-driven mass transfer of the selected gaseous component into the absorption liquid solvent system, and (b) at the back end of said absorber device for kinetic-driven mass transfer of the selected gaseous component into the absorption liquid solvent system;

providing an inverse temperature profile in the absorber device wherein a higher temperature is provided in a section adjacent to said back end of said absorber device relative to a temperature provided in a section at said front end of said absorber device;

recovering said gaseous component from the absorption liquid solvent system;

regenerating said absorption liquid solvent system; and

recycling said absorption liquid solvent system to the absorber device.

15. The process of claim 14, wherein said gas stream is a combustion exhaust gas stream.

16. The process of claim 14, wherein said gas stream is a process gas stream.

17. The process of claim 14, wherein said gas stream flowing from said back end of the absorber device is provided with a two-stage water balance control wherein the first step comprises commingling and contacting the gas stream with a cooled absorption liquid solvent system at the back end of the absorber device, and the second step comprises flowing said gas stream through a condenser interconnected with and communicating with said absorber device.

18. The process of claim 14, wherein said gaseous component is selected from the group comprising CO₂, H₂S, SO₂ and NO_x.

19. The process of claim 14, wherein said kinetic-driven mass transfer is provided by:

(a) controllably cooling said absorption liquid solvent system before it is ingressed into the first section at the back end of the absorber device, and (b) by egressing said solvent system from the first section and controllably heating said solvent system before it is ingressed into the second section of the absorber device.

20. The process of claim 14, wherein the counter-flowing absorption liquid solvent system is progressively enriched with said selected gaseous component as said solvent system progressively sequentially flows through the sections of the absorber device from the back end to the front end of said absorber device.

21. The process of claim 14, wherein said thermodynamic-driven mass transfer is provided by egressing said solvent system from the second section of the absorber device, and controllably cooling said solvent system before it is ingressed into an adjacent section of the absorber device.

22. The process of claim 21, wherein said thermodynamic-driven mass transfer is provided by successively egressing said solvent system from the each of plurality of sections adjacent the second section of the absorber device and controllably cooling said solvent system before it is ingressed into an adjacent section.

23. The process of claim 14, wherein at least a portion of the conditions providing said kinetic-driven mass transfer is derived from heat recovered and transferred from the regenerated absorption liquid solvent system.

24. The process of claim 14, wherein at least a portion of the heat recovered during said thermodynamic-driven mass transfer is transferred to said enriched liquid solvent.

25. The process of claim 14, wherein heat generated during the recovery of the gaseous component from the absorption liquid solvent system is recovered for use in regenerating said solvent system.

26. The process of claim 14, wherein the absorption liquid solvent system comprises at least one chemical compound selected to react with and remove said gaseous component from the gas stream.

27. The process of claim 14, wherein said absorption liquid solvent system comprises at least one first chemical compound selected to react with and remove said gaseous component from the gas stream, and at least one second chemical compound selected from the group comprising kinetic enhancers, corrosion inhibitors, anti-foam chemicals, oxygen scavengers, salt neutralizers, and anti-degradation chemicals.

28. The process of claim 26, wherein said at least one chemical compound is selected from the group comprising monoethanolamine, diglycolamine, diethanolamine, methyldiethanolamine, 2-amino-2-methyl-1-propanol, and piperazine.

29. The process of claim 27, wherein said at least one first chemical compound is selected from the group comprising monoethanolamine, diglycolamine, diethanolamine, methyldiethanolamine, 2-amino-2-methyl-1-propanol, and piperazine.

30. A process for removing and recovering a selected gaseous component from a gas stream, the process comprising:

flowing the gas stream through an absorber device provided with a plurality of sequentially adjacent sections;

delivering a controllably cooled lean absorption liquid solvent to the top section of said absorber device, counterflowing and commingling said cooled lean absorption liquid solvent with the gas stream thereby removing a portion of said gaseous component from the gas stream into said liquid solvent, egressing said liquid solvent from a bottom portion of said top section, and controllably heating the temperature of said egressed liquid solvent;

ingressing the heated liquid solvent into a top portion of a section of the absorber device adjacent to the top section, counterflowing and commingling said heated liquid solvent with said gas stream thereby removing an additional portion of said gaseous component from the gas stream thereby enriching the liquid solvent system with said gaseous component, egressing said liquid solvent from a bottom portion of said the section adjacent to the top section, and controllably cooling the temperature of said egressed liquid solvent;

recovering said gaseous component from the enriched liquid solvent system;

regenerating said liquid solvent into a lean absorption liquid solvent system; and

controllably cooling and delivering said absorption liquid solvent system to the top section of the absorber device.

31. The process of claim 30, wherein the counter-flowing absorption liquid solvent system is progressively enriched with said selected gaseous component as said solvent system progressively flows through the sequentially adjacent sections of the absorber device.

32. The process of claim 30, wherein heat is recovered during said thermodynamic-driven mass transfer within said absorber device, to facilitate recovery of the gaseous component from the absorption liquid solvent system.

33. The process of claim 30, wherein heat generated during the recovery of the gaseous component from the gas stream is recovered for use in regenerating said enriched absorption liquid solvent system.

34. The process of claim 30, wherein heat recovered from the lean absorption liquid solvent is communicated to the absorption liquid solvent egressing from the bottom portion of the top section of said absorber device.

35. The process of claim 30, wherein said gaseous component is selected from the group comprising CO₂, H₂S, SO₂ and NO_x, and said gas stream is selected from the group comprising a combustion exhaust gas stream and a process gas stream.

36. The process of claim 35, wherein the absorption liquid solvent comprises at least one chemical compound selected from group comprising monoethanolamine, diglycolamine, diethanolamine, methyldiethanolamine, 2-amino-2-methyl-1-propanol, and piperazine.

37. The process of claim 36, wherein the absorption liquid solvent additionally comprises at least one chemical compound selected from the group comprising kinetic enhancers, corrosion inhibitors, anti-foam chemicals, oxygen scavengers, salt neutralizers, and anti-degradation chemicals.