Inventors:
Terry G. Hunt - Aurora CO
George R. Offen - Woodside CA
Assignee:
Public Service Company of Colorado - Denver CO
International Classification:
B01J 800, C01B 1700, C01B 2100
Abstract:
A method and apparatus for reducing SO. sub. x and NO. sub. x levels in flue gases generated by the combustion of coal in a boiler in which low NO. sub. x burners and air staging ports are utilized to inhibit the amount of NO. sub. x initially produced in the combustion of the coal, a selected concentration of urea is introduced downstream of the combustion zone after the temperature has been reduced to the range of 1300. degree. F. to 2000. degree. F. , and a sodium-based reagent is introduced into the flue gas stream after further reducing the temperature of the stream to the range of 200. degree. F. to 900. degree. F. Under certain conditions, calcium injection may be employed along with humidification of the flue gas stream for selective reduction of the pollutants.