Steam mill system useful for mercury control
View Patent ↗A steam mill system for transport of powdered activated carbon (PAC) from a storage silo to a steam powered jet mill to produce milled sorbent for use in a coal-fired power plant flue gas for mercury control. More specifically, the present disclosure relates to a cyclone separator arranged in a PAC transport line prior to a steam powered jet mill for separation of PAC according to particle size for the purpose of achieving reductions in associated compressed air usage, operating costs and capital costs.
1. A system for processing carbonaceous sorbent comprising:
a sorbent silo;
a cyclone separator supplied sorbent from the sorbent silo for separating the sorbent supplied into larger sorbent particulates and smaller sorbent particles;
a steam powered jet mill for milling larger sorbent particulates to produce milled sorbent;
an air line for transport of smaller sorbent particles for injection of the smaller sorbent particles into a boiler flue gas containing mercury for mercury adsorption by the smaller sorbent particles; and
a steam line for transport of milled sorbent for injection of milled sorbent into a boiler flue gas containing mercury for mercury adsorption by the milled sorbent.
2. The system according to claim 1 , wherein the smaller sorbent particles are transported in an air line.
3. The system according to claim 1 , wherein the milled sorbent is transported in a steam line.
4. The system according to claim 1 , wherein the smaller sorbent particles are about 3 to about 18 microns in size.
5. The system according to claim 1 , wherein the larger sorbent particulates are about 9 to about 30 microns in size.
6. The system according to claim 1 , wherein the milled sorbent particulates are about 3 to about 18 microns in size.
7. The system according to claim 1 , wherein the cyclone separator releases pressure into a transport line upon an obstruction in the transport of smaller sorbent particles or milled sorbent.
8. The system according to claim 1 , wherein an injector for injection of milled sorbent is operated at an operation rate the same as an operation rate of the cyclone separator.
9. A method for processing carbonaceous sorbent comprising:
providing a sorbent silo for supply of a carbonaceous sorbent to a cyclone separator for separating the carbonaceous sorbent into larger sorbent particulates and smaller sorbent particles;
using a steam powered jet mill for milling larger sorbent particulates to produce milled sorbent;
transporting smaller sorbent particles to injection into a boiler flue gas containing mercury for mercury adsorption by the smaller sorbent particles; and
transporting milled sorbent to injection into a boiler flue gas containing mercury for mercury adsorption by the milled sorbent.
10. The method according to claim 9 , wherein the smaller sorbent particles are transported in an air line.
11. The method according to claim 9 , wherein the milled sorbent is transported in a steam line.
12. The method according to claim 9 , wherein the smaller sorbent particles are about 3 to about 18 microns in size.
13. The method according to claim 9 , wherein the larger sorbent particulates are about 9 to about 30 microns in size.
14. The method according to claim 9 , wherein the milled sorbent particulates are about 3 to about 18 microns in size.
15. The method according to claim 9 , wherein the cyclone separator releases pressure into a transport line upon obstruction in transporting smaller sorbent particles or milled sorbent.