Study on the NOx Emission during the Combustion of Low-Quality Anthracite Coal in Supercritical Pressure W-Shaped Flame Boiler

Abstract

The combustion of pulverized coal in supercritical pressure W-shaped flame boiler is efficient.To decrease the formation of NOx in the furnace some reasonable measures are supposed to be taken to obtain low NOx combustion. In light of a 600MW supercritical pressure W-flame boiler, the combustion of low-quality anthracite coal and the formation of NO in the furnace are numerical simulated. The influence of concentration of pulverized coal, velocity of the primary air and the air distribution on the front and rear wall to the formation of NO is studied. The results indicate that NO emission at furnace exit can be effectively decreased by increasing the concentration of pulverized coal. Compared with the conventional concentration, NO emission can be decreased by 42%. The NO formation in the furnace can be controlled by selecting a reasonable primary air velocity on the front and rear arch, and there is a best primary air velocity. The study of supercritical W-flame boiler has great reference significance for the combustion adjustment and operation of large capacity W-shape flame boiler.