Systems and methods for carbon capture
The present disclosure provides systems for carbon capture in combination with production of one or more industrially useful materials. The disclosure also provides methods for carrying out carbon capture in combination with an industrial process. In particular, carbon capture can include carrying out calcination in a reactor, separation of carbon dioxide rich flue gases from industrially useful products, and capture of at least a portion of the carbon dioxide for sequestration of other use, such as enhanced oil recovery.
1. A method for calcination with carbon capture, the method comprising:
processing a carbonate-containing raw material in a heated reactor to provide a decomposition stream comprising at least solids and carbon dioxide gas, the reactor being heated through combustion of a fuel in the reactor with an oxidant, wherein the oxidant comprises a flue gas;
separating the decomposition stream in a separation unit into a gas stream including the carbon dioxide and a solids stream;
cooling one or both of the gas stream including the carbon dioxide and the solids stream in a heat exchanger;
one or both of providing at least a portion of the solids stream as a product for export and delivering at least a portion of the solids stream to a further reactor for forming a secondary product; and
purifying the gas stream including the carbon dioxide to provide a substantially pure stream of carbon dioxide for export.
2. The method of claim 1 , wherein the reactor is operated at a pressure of about 1.5 bar to about 8 bar.
3. The method of claim 1 , wherein the reactor is operated at a temperature of about 850° C. to about 1100° C.
4. The method of claim 1 , wherein the heated reactor and the separation unit are an integral unit.
5. The method of claim 1 , wherein the heat exchanger is one or more of a heat recovery steam generator (HRSG), a gas heated reformer (GHR), or a recuperative heat exchanger.
6. The method of claim 1 , wherein the gas stream including the carbon dioxide is cooled in the heat exchanger to a temperature of about 20° C. to about 150° C.
7. The method of claim 6 , further comprising passing the gas stream including the carbon dioxide exiting the heat exchanger through one or more water removal units to provide a dried gas stream including the carbon dioxide.
8. The method of claim 7 , wherein purifying the gas stream including the carbon dioxide comprises passing the gas stream including the carbon dioxide through at least one membrane separation stage configured to separate the gas stream including the carbon dioxide into a CO 2 lean stream and a CO 2 rich stream.
9. The method of claim 8 , further comprising passing at least the CO 2 rich stream through a low temperature CO 2 purification unit.
10. The method of claim 8 , further comprising compressing the gas stream including the carbon dioxide upstream from the at least one membrane separation stage.
11. The method of claim 10 , further comprising expanding at least the CO 2 rich stream downstream from the at least membrane separation stage.
12. The method of claim 8 , wherein the at least membrane separation stage is configured to provide at least 50% bulk recovery of CO 2 from the gas stream including the carbon dioxide in the CO 2 rich stream.
13. The method of claim 12 , wherein the CO 2 rich stream has a CO 2 concentration no lower than 50%.
14. The method of claim 1 , further comprising carrying out a power production cycle that is integrated with the heat exchanger.
15. The method of claim 14 , wherein the power production cycle comprises compressing a working fluid in a compression unit to provide a compressed working fluid, heating the compressed working in the heat exchanger, passing the compressed working fluid exiting the heat exchanger through a turbine to generate power and form an expanded working fluid, and passing the expanded working fluid back to the compression unit.
16. The method of claim 1 , further comprising processing a portion of the solids stream exiting the separator in a carbonator.
17. The method of claim 16 , wherein the carbonator is configured to provide a regenerated raw material, and wherein at least a portion of the regenerated raw material is recycled back to the reactor.
18. The method of claim 16 , wherein the raw material is limestone (CaCO 3 ), and wherein the solids steam exiting the reactor comprises quicklime (CaO).
19. The method of claim 18 , further comprising process a flue gas including carbon dioxide through the carbonator such that at least a portion of the carbon dioxide from the flue gas is reacted with the quicklime to form CaCO 3 .
20. The method of claim 1 , further comprising processing a portion of the solids stream exiting the separator in a clinker unit.
21. The method of claim 20 , further comprising adding one or more raw materials effective for cement production into the clinker unit such that solids from the solids stream react with the one or more raw materials effective for cement production to form cement clinker.
22. The method of claim 21 , further comprising passing the cement clinker through a clinker cooler unit so as to cool the cement clinker using a cooled portion of the gas stream including the carbon dioxide.
23. The method of claim 22 , further comprising recycling at least a portion of a flue gas from the clinker unit back to the reactor.
24. The method of claim 1 , further comprising integrating the method for calcination with carbon capture into a steel-making process.
25. The method of claim 1 , further comprising injecting coal ash into one or both of the reactor and a separate burner.
26. The method of claim 25 , further comprising recovering thermally treated coal ash from one or both of the reactor and the separate burner.
27. The method of claim 26 , further comprising mixing at a least a portion of the thermally treated coal ash with quicklime.
28. The method of claim 1 , wherein the heated reactor is heated by combustion of a fuel that comprises sour gas.
29. The method of claim 28 , comprising reacting the sour gas in the reactor with CaCO 3 to form gypsum.
30. The method of claim 1 , wherein the flue gas is from a different process.
31. The method of claim 1 , wherein the flue gas is from a power production plant.
32. The method of claim 1 , wherein the flue gas is from a separate industrial process that is optionally operated in combination with the calcination with carbon capture.