Systems and methods for removing combustion products from a power generation cycle

Patent metadata

Field	Value
Publication number	US-9919268-B2
Application number	US-201615298975-A
Country	US
Kind code	B2
Filing date	Oct 20, 2016
Priority date	Oct 21, 2015
Publication date	Mar 20, 2018
Grant date	Mar 20, 2018

Abstract

The present disclosure relates to a system for removing a pollutant from a power generation cycle that utilizes a high pressure circulating fluid. The system includes a first direct contact cooling tower configured to cool the high pressure circulating fluid and condense a fluid stream that removes SO 2 from the circulating fluid. A first recirculating pump fluidly communicates with the first direct contact cooling tower. The first tower includes an outlet configured to circulate a cooled CO 2 product stream, and a second direct contact cooling tower is configured to receive at least a portion of the cooled CO 2 product stream from the outlet. The second direct contact cooling tower is configured to cool the CO 2 product stream and condense a fluid stream that removes NO x from the CO 2 product stream. A second recirculating pump fluidly communicates with the second tower. An associated method is provided.

First claim

That which is claimed:

1. A method for removing an acid gas from a power cycle product stream, the method comprising:
carrying out a power production cycle;
directing a product stream containing CO 2 , SO x , and NO x from the power production cycle into a first direct contact cooling tower;
contacting the product stream containing CO 2 , SO x , and NO x in the first direct contact cooling tower with a first counter-current circulating aqueous liquid stream;
removing at least a portion of SO 2 present in the product stream in the first direct contact cooling tower via reaction between the SO 2 and NO 2 in the product stream in the presence of the aqueous liquid stream;
withdrawing from the first direct contact cooling tower a recycle stream containing CO 2 and NO x ; and
delivering at least a portion of the recycle stream containing CO 2 and NO x back into the power production cycle.

2. The method according to claim 1 , wherein the first counter-current circulating aqueous liquid stream comprises H 2 SO 4 .

3. The method according to claim 1 , wherein the product stream containing CO 2 , SO x , and NO x contains at least 10 ppm NO x based on the total mass of the product stream containing CO 2 , SO x , and NO x .

4. The method according to claim 1 , wherein the NOx concentration in the product stream containing CO 2 , SO x , and NO x is controlled within a range such that less than 50% by mass of the NO x in the product stream containing CO 2 , SO x , and NO x is converted to HNO 3 in the first direct contact cooling tower.

5. The method according to claim 1 , wherein the recycle stream containing CO 2 and NO x that is withdrawn from the first direct contact cooling tower includes at least 90% by mass of the NOx present in the product stream containing CO 2 , SO x , and NO x that is introduced into the first direct contact cooling tower.

6. The method according to claim 1 , wherein the recycle stream containing CO 2 and NO x that is withdrawn from the first direct contact cooling tower includes substantially no SO 2 or contains SO 2 in an amount of less than 50 ppm based on the total mass of the recycle stream containing CO 2 and NO x .

7. The method according to claim 1 , wherein the concentration of NO x in the product stream containing CO 2 , SO x , and NO x is adjusted by adding NOx upstream from the first direct contact cooling tower.

8. The method according to claim 7 , wherein NO x is added upstream from the first direct contact cooling tower by combining a nitrogen source with a fuel and an oxidant in a combustor upstream from the first direct contact cooling tower.

9. The method according to claim 7 , wherein NO x is added directly to the product stream containing CO 2 , SO x , and NO x upstream from the first direct contact cooling tower.

10. The method according to claim 9 , wherein the NO x that is added directly to the product stream containing CO 2 , SO x , and NO x upstream from the first direct contact cooling tower is generated from ammonia.

11. The method according to claim 1 , wherein the concentration of NO x in the product stream containing CO 2 , SO x , and NO x is adjusted by increasing or decreasing a discharge flow from a first recirculating pump that is configured to receive a liquid product stream from the first direct contact cooling tower and recirculate the liquid product stream into the first direct contact cooling tower.

12. The method according to claim 1 , wherein at least a portion of the NO x in the recycle stream containing CO 2 and NO x is directed back into the power production cycle.

13. The method according to claim 1 , wherein the recycle stream containing CO 2 and NO x is divided into a recirculating working fluid stream that is directed back into the power production cycle and a net CO 2 product stream.

14. The method according to claim 1 , further comprising:
directing at least a portion of the recycle stream containing CO 2 and NO x into a second direct contact cooling tower;
contacting the recycle stream containing CO 2 and NO x in the second direct contact cooling tower with a second counter-current circulating aqueous liquid stream;
removing at least a portion of NO 2 from the recycle stream containing CO 2 and NO x in the second direct contact cooling tower via reaction between the NO 2 and water; and
withdrawing from the second direct contacting cooling tower a stream containing CO 2 .

15. The method according to claim 14 , wherein the second counter-current circulating aqueous liquid stream comprises HNO 3 .

16. The method according to claim 14 , further comprising adding O 2 to the recycle stream containing CO 2 and NO x prior to directing the recycle stream containing CO 2 and NO x into the second direct contact cooling tower.

17. The method according to claim 14 , wherein prior to directing at least a portion of the recycle stream containing CO 2 and NO x into the second direct contact cooling tower, the recycle stream containing CO 2 and NO x is compressed utilizing a compressor in the power production cycle.

18. The method according to claim 14 , wherein the recycle stream containing CO 2 and NO x is divided into a recirculating portion that is directed back into the power production cycle and a net production portion that is directed to the second direct contact cooling tower.

19. A system for removing an acid gas from a power cycle product stream, the system comprising:
a transfer element configured to deliver a power cycle product stream containing CO 2 , SO x , and NO x from a component of a power cycle;
a first direct contact cooling tower configured to receive the power cycle product stream containing CO 2 , SO x , and NO x from the component of the power cycle under reaction conditions such that at least a portion of SO 2 is removed therefrom and a recycle stream containing CO 2 and NO x is output from the first direct contact cooling tower;
a first recirculating pump in fluid communication with the first direct contact cooling tower configured to receive a liquid stream from the first direct contact cooling tower and recirculate at least a portion of the liquid stream to the first direct contact cooling tower; and
a transfer element configured to deliver at least a portion of the recycle stream containing CO 2 and NO x to a component of the power cycle.

20. The system according to claim 19 , further comprising:
a second direct contact cooling tower configured to receive at least a portion of the recycle stream containing CO 2 and NO x from the first direct contact cooling tower under reaction conditions such that at least a portion of NO 2 in the recycle stream containing CO 2 and NO x is removed therefrom and a stream containing CO 2 is output from the second direct contact cooling tower; and
a second recirculating pump in fluid communication with the second direct contact cooling tower configured to receive a liquid stream from the second direct contact cooling tower and recirculate at least a portion of the liquid stream to the second direct contact cooling tower.

21. The system according to claim 19 , further comprising an O 2 input positioned upstream from the second direct contact cooling tower and downstream from the first direct contact cooling tower.

22. The system according to claim 19 , further comprising a compressor positioned upstream from the second direct contact cooling tower and downstream from the first direct contac

Assignees

• 8 Rivers Capital Llc

Inventors

• Allam Rodney John
• Lu Xijia
• Martin Scott Thomas

Classifications

• C01B32/50

  Carbon dioxide · CPC title

• B01D2257/404

  Nitrogen oxides other than dinitrogen oxide · CPC title

• B01D53/56

  Nitrogen oxides (B01D53/60 takes precedence) · CPC title

• F23J2219/40

  Sorption with wet devices, e.g. scrubbers · CPC title

• B01D2257/602

  Mercury or mercury compounds · CPC title