Methods of manufacturing mercury sorbents and removing mercury from a gas stream
Sorbents for removal of mercury and other pollutants from gas streams, such as a flue gas stream from coal-fired utility plants, and methods for their manufacture and use are disclosed. The methods include injecting fluid cracking catalyst particles into a flue gas stream.
1. A method of removing mercury and other pollutants from a flue gas stream comprising injecting a sorbent comprising recovered and separated particles from an intermediate stage of a fluid cracking catalyst (FCC) particle manufacturing process into the flue gas stream.
2. The method of claim 1 , wherein the particles are fine particles.
3. The method of claim 2 , wherein the particles contain essentially no added metal sulfides on the surface of the particles.
4. The method of claim 2 , wherein the particles have an average particle diameter of less than about 40 microns.
5. The method of claim 4 , wherein the particles have an average particle diameter of between about 20 microns and 40 microns.
6. The method of claim 4 , wherein the particles have an average particle diameter of less than about 20 microns.
7. The method of claim 1 , wherein the particles contain at least one of zeolite, hydrous kaolin, metakaolin, sodium silicate, silica, and alumina.
8. The method of claim 7 , wherein the content of each component is in the range from zero to 100% by weight.
9. The method of claim 7 , wherein the zeolite is a y-type zeolite.
10. The method of claim 7 , wherein the particles are obtained from an intermediate stage of a FCC manufacturing process are separated by one or more of a centrifuge, settling and filtration.
11. The method of claim 10 , wherein the zeolite particles are obtained prior to ion exchange.
12. The method of claim 10 , wherein the particles are obtained after ion exchange.
13. The method of claim 10 , wherein the particles are obtained after calcination.
14. A method of absorbing mercury from a mercury-containing gas stream comprising recovering FCC fine particles from an intermediate stage of a FCC particle manufacturing process; and providing the FCC fine particles as a sorbent in the gas stream to remove mercury.
15. The method of claim 14 , wherein the FCC particles are recovered prior to ion exchange.
16. The method of claim 14 , wherein the FCC particles comprise Y-type zeolite.