Method for flue-gas reduction of pollutants in combustion processes
View Patent ↗Systems and methods for reduction of pollutants in combustion processes using combined rotating opposed fired air (ROFA) and fuel injection sorbents (FSI) for increased chemical reactivity.
1. A method of reducing SO 2 flue gas concentration in a combustion process utilizing a sulfurous fuel, comprising the steps of:
providing a staged combustion system for application in a reactor, the staged combustion system having asymmetrical injection devices for introducing at least one sorbent to the reactor by asymmetrical injection at predetermined, spaced apart locations;
injecting the fuel with a primary air through a first stage prior to injection of a secondary air;
injecting the secondary air and at least one sorbent through the injection devices; and
controlling the asymmetrical injection of the secondary air to produce a turbulence resulting in dispersion of the sorbent into the reaction system, thereby providing increased reaction and reactor efficiency and reduced SO 2 .
2. The method of claim 1 , wherein the staged combustion system includes at least two stages.
3. The method of claim 1 , wherein the staged combustion system includes at least three stages.
4. The method of claim 1 , wherein the staged combustion system includes at least one ROFA stage, and at least one FSI stage.
5. The method of claim 4 , wherein the staged combustion system includes a primary stage, at least one ROFA stage, and at least one FSI stage.
6. The method of claim 4 , wherein the FSI stage and the ROFA stage are co-injected.
7. The method of claim 4 , wherein the FSI stage and the ROFA stage are separate.
8. The method of claim 4 , wherein the ROFA stage is upstream from the FSI stage.
9. The method of claim 6 , wherein the FSI stage and the ROFA stage are injected co-axially.
10. A method for reducing pollutant formation, comprising the steps of:
providing a staged combustion system including at least one FSI stage, and a furnace with asymmetrical injection ports introducing at least one sorbent to the furnace by asymmetrical injection at predetermined, spaced apart locations;
injecting the fuel with a primary air through a first stage prior to injection of a secondary air;
injecting secondary air and at least one sorbent through the injection ducts; and
controlling the asymmetrical injection of secondary air to produce a turbulence resulting in dispersion of the sorbent into the furnace, thereby providing increased reaction and reactor efficiency and reduced NOx formation.
11. The method of claim 10 , wherein lime is injected to reduce NOx.
12. The method of claim 10 , wherein lime is injected to reduce Hg.
13. The method of claim 10 , wherein the staged combustion system includes at least two stages.
14. The method of claim 10 , wherein the staged combustion system includes at least three stages.
15. The method of claim 10 , wherein the staged combustion system includes at least one ROFA stage, and at least one FSI stage.
16. The method of claim 15 , wherein the staged combustion system includes a primary stage, at least one ROFA stage, and at least one FSI stage.
17. The method of claim 15 , wherein the FSI stage and the ROFA stage are co-injected.
18. The method of claim 15 , wherein the FSI stage and the ROFA stage are separate.
19. The method of claim 15 , wherein the ROFA stage is upstream from the FSI stage.
20. The method of claim 15 , wherein the FSI stage and the ROFA stage are injected co-axially.
21. A method of reducing pollutant flue gas concentration in a combustion process utilizing a sulfurous fuel, comprising the steps of:
providing a staged combustion system for application in a reactor, the staged combustion system having asymmetrical injection devices for introducing at least one sorbent to the reactor by asymmetrical injection at predetermined, spaced apart locations;
injecting the fuel with a primary air through a first stage prior to injection of a secondary air;
injecting the secondary air and at least one sorbent through the injection devices; and
controlling the asymmetrical injection of the secondary air to produce a turbulence resulting in dispersion of the sorbent into the reaction system, thereby providing increased reaction and reactor efficiency and reduced SO 2 ;
wherein the staged combustion system includes ROFA and FSI in combination for providing increased reactivity within a predetermined zone of the reactor, thereby producing more complete, more effective, and more efficient reduction of pollutants therein.
22. The method of claim 21 , wherein the FSI stage and the ROFA stage are co-injected.
23. The method of claim 21 , wherein the FSI stage and the ROFA stage are separate.
24. The method of claim 21 , wherein the ROFA stage is upstream from the FSI stage.
25. The method of claim 21 , wherein the FSI stage and the ROFA stage are provided co-axially.