CARBON DIOXIDE CAPTURE PROCESS WITH CATALYTICALLY-ENHANCED SOLVENT AND PHASE SEPARATION

• US 20130260442A1
• Filed: 03/29/2012
• Published: 10/03/2013
• Est. Priority Date: 03/29/2012
• Status: Abandoned Application

• Current Assignee: Alstom Technology Ltd. (Alstom SA)
• Original Assignee: Alstom Technology Ltd. (Alstom SA)
• Inventors: Vitse, Frederic
• Application Number:
  US13/433,694
• Publication Number:
  US 20130260442A1
• Time in Patent Office: Days
• US Class Current: 435/266
• CPC Class Codes: B01D 2252/20431 Tertiary amines
• CPC Class Codes: B01D 2252/20494 Amino acids, their salts or derivatives
• CPC Class Codes: B01D 2252/602 Activators, promoting agents, catalytic agents or enzymes
• CPC Class Codes: B01D 2257/504 Carbon dioxide
• CPC Class Codes: B01D 2258/0283 Flue gases
• CPC Class Codes: B01D 53/1425 Regeneration of liquid absorbents
• CPC Class Codes: B01D 53/1475 Removing carbon dioxide
• CPC Class Codes: B01D 53/1493 Selection of liquid materials for use as absorbents
• CPC Class Codes: B01D 53/62 Carbon oxides
• CPC Class Codes: Y02A 50/20 Air quality improvement or preservation, e.g. vehicle emission control or emission reduction by using catalytic converters
• CPC Class Codes: Y02C 20/40 of CO2

Abstract

A system for the regeneration of carbon dioxide from a flue gas comprises an absorption vessel configured to receive a catalytically-enhanced solvent stream and a flue gas stream having CO₂, the catalytically-enhanced solvent stream and the flue gas stream being contacted in the absorption vessel to provide a catalytically-enhanced CO₂-rich outlet stream; a crystallizer configured to receive the catalytically-enhanced CO₂-rich outlet stream from the absorption vessel and produce a two-phase outlet solvent stream having crystals; a separator configured to receive the outlet solvent stream having crystals and separate the outlet solvent stream having crystals into a catalyst solvent stream and a CO₂-rich non-catalyst solvent stream; and a regenerator vessel configured to receive the CO₂-rich non-catalyst solvent stream from the separator and produce a CO₂ stream and a regenerator outlet solvent stream, the regenerator outlet solvent stream combined with catalyst for return to the absorption vessel as the catalytically-enhanced solvent stream.

Claims

1. A system for the regeneration of carbon dioxide from a flue gas, the system comprising:

A CO₂ capture system configured to receive a catalytically-enhanced solvent stream and a flue gas stream having CO₂, the catalytically-enhanced solvent stream and the flue gas stream being contacted in the CO₂ capture system to provide a catalytically-enhanced CO₂-rich outlet stream;

a catalyst treatment system configured to receive the catalytically-enhanced CO₂-rich outlet stream from the CO₂ capture system and produce a two-phase outlet solvent stream having crystals;

a separation apparatus configured to receive the outlet solvent stream having crystals and separate the outlet solvent stream having crystals into a catalyst solvent stream and a CO₂-rich non-catalyst solvent stream; and

a CO₂ regeneration apparatus configured to receive the CO₂-rich non-catalyst solvent stream from the separation apparatus and produce a CO₂ stream and a regenerator outlet solvent stream, the regenerator outlet solvent stream being combined with catalyst for return to the CO₂ capture system as the catalytically-enhanced solvent stream.

2. The system of claim 1, wherein the catalytically-enhanced solvent stream received into the CO₂ capture system comprises a CO₂-lean stream having catalyst and a CO₂-semi-lean stream having catalyst.

3. The system of claim 1, wherein the separation apparatus is a cyclone separator.

4. The system of claim 1, further comprising a heat exchanger positioned between the CO₂ regeneration apparatus and the separation apparatus and configured to exchange heat between the regenerator outlet solvent stream and the CO₂-rich non-catalyst solvent stream from the separation apparatus.

5. The system of claim 1, wherein the CO₂ regeneration apparatus is a stripping column.

6. The system of claim 5, further comprising a reboiler in fluid communication with the stripping column.

7. The system of claim 1, further comprising a sequestration apparatus in communication with the CO₂ regeneration apparatus and configured to receive the CO₂ stream therefrom.

8. The system of claim 1, wherein the catalytically-enhanced solvent stream comprises an amine-based solvent selected from the group consisting of tertiary amines and amino acids.

9. The system of claim 1, wherein a catalyst in the catalytically-enhanced solvent stream comprises an enzyme.

10. A system for the capture, regeneration, and sequestration of CO₂, the system comprising:

a packed column comprising a vessel and a packing material therein, the packed column configured to receive a catalytically-enhanced amine-based solvent stream and a flue gas stream having CO₂, the catalytically-enhanced amine-based solvent stream and the flue gas stream being contacted in the packed column in a counter-current arrangement to provide a catalytically-enhanced CO₂-rich outlet stream;

a crystallizer configured to receive the catalytically-enhanced CO₂-rich outlet stream from the absorption vessel and produce a two-phase outlet solvent stream having crystals;

a cyclone separator configured to receive the outlet solvent stream having crystals and separate the outlet solvent stream having crystals into a catalyst solvent stream and a CO₂-rich non-catalyst solvent stream;

a stripping column configured to receive the CO₂-rich non-catalyst solvent stream from the cyclone separator and produce a CO₂ stream and an outlet solvent stream, the outlet solvent stream being combined with catalyst for return to the packed column as the catalytically-enhanced amine-based solvent stream; and

a sequestration apparatus in communication with the stripping column and configured to receive the CO₂ stream therefrom.

11. The system of claim 10, further comprising a heat exchanger positioned between the cyclone separator and the stripping column and configured to exchange heat between the outlet solvent stream and the CO₂-rich non-catalyst solvent stream from the cyclone separator.

12. The system of claim 10, further comprising a reboiler in communication with the stripping column.

13. The system of claim 10, further comprising a reflux drum in fluid communication with the stripping column.

14. The system of claim 10, wherein the catalytically-enhanced amine-based solvent stream comprises at least one of a tertiary amine and an amino acid.

15. The system of claim 10, wherein a catalyst in the catalytically-enhanced amine-based solvent stream comprises an enzyme.

16. A method for removing CO₂ from a flue gas, the method comprising:

contacting a catalytically-enhanced amine-based solvent stream and a flue gas stream having CO₂ in an absorption vessel, the catalytically-enhanced amine-based solvent stream and the flue gas stream being contacted in the absorption vessel in a counter-current arrangement;

directing a catalytically-enhanced CO₂-rich outlet stream from the absorption vessel to a crystallizer;

forming the catalytically-enhanced CO₂-rich outlet stream in the crystallizer into a first phase having catalyst and solvent and a second phase having solvent and CO₂;

directing the first phase back to the absorption vessel;

directing the second phase to a stripping column;

stripping the second phase having solvent and CO₂ to separate the solvent from the CO₂;

sequestering the CO₂ from the second phase; and

returning the solvent from the second phase back to the absorption vessel.

17. The method of claim 16, further comprising transferring heat from the solvent being returned from the stripping column to the absorption vessel to the second phase directed to the stripping column.

18. The method of claim 16, further comprising water-washing the solvent in the absorption vessel.

19. The method of claim 16, wherein the step of forming the catalytically-enhanced CO₂-rich outlet stream in the crystallizer into a first phase having catalyst and solvent comprises precipitating the catalyst using potassium carbonate.

20. The method of claim 16, wherein the step of forming the catalytically-enhanced CO₂-rich outlet stream in the crystallizer into a first phase having catalyst and solvent and a second phase having solvent and CO₂ comprises cooling the amine-based solvent into a thermodynamic region such that the solubility limit of the CO₂ in the amine-based solvent is exceeded.