Evaluation of Gas/Coal Cofiring and Gas/Gas Reburning for Emissions Control on a Tangentially-Fired Boiler. Final Report, September 1991-September 1992

摘要

Field tests on a 71 MWe tangentially-fired boiler showed that gas/coal cofiring and gas/gas reburning are effective in reducing pollutant emissions. For 34 percent gas cofiring, NOx, SO2, and CO2 emissions were reduced by 35-45, 34, and 12 percent, respectively, compared to 100 percent coal firing. The use of overfire air combined with gas cofiring resulted in NOx reductions of up to 65 percent. Carbon in ash was reduced by 20-30 percent. Heat efficiency was reduced by 1.72 percent due to the increased moisture content of the combined flue gas. There was no change in boiler exit gas temperature, main steam and reheat steam temperatures. Changes in attemperation flow rates were minor.