Process gas treatment system

• US 8,623,307 B2
• Filed: 09/14/2010
• Issued: 01/07/2014
• Est. Priority Date: 09/14/2010
• Status: Active Grant

• Current Assignee: General Electric Technology GmbH (GE Vernova, Inc.)
• Original Assignee: Alstom Technology Ltd. (Alstom SA)
• Inventors: Koss, Peter Ulrich, Koch, Michael, Naumovitz, Joseph P.
• Primary Examiner(s): Hendrickson, Stuart
• Assistant Examiner(s): BERNS, DANIEL J
• Application Number:
  US12/881,485
• Publication Number:
  US 20120063975A1
• Time in Patent Office: 1,211 Days
• Field of Search: 423/220, 423/234
• US Class Current: 423/234
• CPC Class Codes: B01D 2252/102 Ammonia
• CPC Class Codes: B01D 2257/504 Carbon dioxide
• CPC Class Codes: B01D 53/1425 Regeneration of liquid absorbents
• CPC Class Codes: B01D 53/1475 Removing carbon dioxide
• CPC Class Codes: B01D 53/62 Carbon oxides
• CPC Class Codes: B01D 53/96 Regeneration, reactivation or recycling of reactants
• 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 is arranged to remove carbon dioxide (CO2) from a gas stream by bringing the gas stream into contact with a circulating ammoniated solution stream such that CO2 is removed from the gas stream by the ammoniated solution stream. A method of removing non-volatile compounds from the circulating ammoniated solution stream includes: introducing a portion of the circulating ammoniated solution stream into a gas-liquid separating device; and separating the introduced ammoniated solution into an ammonia rich gas phase and a liquid phase comprising the non-volatile compounds; and reintroducing the ammonia rich gas phase into the circulating ammoniated solution stream.

Claims

1. A method of removing non-volatile compounds from a circulating ammoniated solution stream of a CO2 removal system, the system being arranged to remove carbon dioxide (CO2) from a gas stream by bringing the gas stream into contact with the circulating ammoniated solution stream such that CO2 is removed from the gas stream by the circulating ammoniated solution stream, wherein the CO2 removal system includes:

a CO2 capture arrangement comprising a CO2 absorber configured to receive the gas stream containing CO2 and contacting the gas stream with the ammoniated solution stream such that CO2 is removed from the gas stream by the circulating ammoniated solution stream to form a CO2 rich ammoniated solution stream; and

a regeneration arrangement comprising a regenerator configured to receive the CO2 rich ammoniated solution stream from the CO2 capture arrangement, and to separate CO2 from the ammoniated solution to form a CO2 lean ammoniated solution stream, and to return said CO2 lean ammoniated solution stream to the CO2 capture arrangement;

said method comprising;

providing a portion of the circulating ammoniated solution stream having non-volatile compounds into a gas-liquid separating device;

separating the portion of the circulating ammoniated solution stream into an ammonia rich gas phase and a liquid phase comprising the non-volatile compounds; and

providing the ammonia rich gas phase into the circulating ammoniated solution stream provided to the regenerator.

2. The method of claim 1, wherein the portion of the circulating ammoniated solution stream has a pressure in the range of 1 to 10 bar when it is introduced into the gas-liquid separating device.

3. The method of claim 1, wherein the portion of the circulating ammoniated solution stream has a pressure in the range of 10 to 30 bar when it is introduced into the gas-liquid separating device.

4. The method of claim 1, wherein the portion of the circulating ammoniated solution stream is a portion of the CO2 lean ammoniated solution stream from the regeneration arrangement.

5. The method of claim 1, wherein the non-volatile compounds comprise salts and metals.

6. The method of claim 1, wherein the providing of the portion of the circulating ammoniated solution stream to the gas-liquid separating device comprises:

providing the portion of the circulating ammoniated solution stream to the gas-liquid separating device above a mass transfer device disposed in the gas-liquid separating device.

7. The method of claim 1, further comprising:

transferring heat from the liquid phase to the providing of the portion of the circulating ammoniated solution stream provided to the gas-liquid separating device.

8. The method of claim 1, wherein the portion of the circulating ammoniated solution stream is a portion of the CO2 rich ammoniated solution stream from the CO2 capture arrangement.

9. The method of claim 8, further comprising:

providing a portion of the CO2 lean ammoniated solution stream from the regeneration arrangement to the gas-liquid separating device.

10. The method of claim 8, further comprising;

providing a second gas stream having ammonia from a second gas-liquid separating device to the gas-liquid separating device.

11. The method of claim 10, wherein the providing the second gas stream is provided to the gas-liquid separating device at a point intermediate to a pair of vertically spaced mass transfer devices disposed in the gas-liquid separating device.

12. The method of claim 11, wherein the providing of the portion of the circulating ammoniated solution stream to the gas-liquid separating device comprises:

providing the portion of the circulating ammoniated solution stream to the gas-liquid separating device above the pair of mass transfer devices.

13. The method of claim 1, wherein the gas-liquid separating device comprises a stripper.

14. The method of claim 13, wherein the stripper is heated by steam having a pressure of less than 10 bar.

15. The method of claim 13, wherein the stripper is heated by CO2 lean ammoniated solution from the regenerator.

16. A method of removing non-volatile compounds from a circulating ammoniated solution stream of a CO2 removal system, the system being arranged to remove carbon dioxide (CO2) from a gas stream by bringing the gas stream into contact with the circulating ammoniated solution stream such that CO2 is removed from the gas stream by the circulating ammoniated solution stream, said method comprising:

introducing a portion of the circulating ammoniated solution stream having non-volatile compounds into a gas-liquid separating device, wherein the portion of the circulating ammoniated solution stream is aqueous;

separating the portion of the circulating ammoniated solution stream into an ammonia rich gas phase and a liquid phase comprising the non-volatile compounds, wherein a major portion of the water of the portion of the circulating ammoniated solution stream is separated into the ammonia rich gas phase and a minor portion of the water of the ammoniated solution is separated into the liquid phase comprising the non-volatile compounds; and

reintroducing the ammonia rich gas phase into the circulating ammoniated solution stream.

17. A method of removing non-volatile compounds from a circulating ammoniated solution stream of a CO2 removal system, the system being arranged to remove carbon dioxide (CO2) from a gas stream by bringing the gas stream into contact with the circulating ammoniated solution stream such that CO2 is removed from the gas stream by the circulating ammoniated solution stream, said method comprising:

introducing a portion of the circulating ammoniated solution stream having non-volatile compounds into a gas-liquid separating device, wherein the portion of the circulating ammoniated solution stream introduced into the gas-liquid separating device has a flow rate which is less than 25% by volume of the flow rate of the circulating ammoniated solution stream;

separating the portion of the circulating ammoniated solution stream into an ammonia rich gas phase and a liquid phase comprising the non-volatile compounds; and

reintroducing the ammonia rich gas phase into the circulating ammoniated solution stream.