Integrated process and apparatus for control of pollutants in coal-fired boilers

Patent · Wed Jan 01 04:00:00 EST 1992

OSTI ID:868552

Hunt, Terry G ^[1]; Offen, George R ^[2]

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1. Aurora, CO
2. Woodside, CA

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.

• Research Organization: Public Service Co. of Colorado, Denver, CO (United States)
• DOE Contract Number: FC22-91PC90550
• Assignee: Public Service Company of Colorado (Denver, CO)
• Patent Number(s): US 5165903
• OSTI ID: 868552
• Country of Publication: United States
• Language: English

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