Parametric study of reburning of nitrogen oxide for superfine pulverized coal

An experimental investigation of process parameters design by superfine pulverized coal reburning on NOx reduction is carried out in a one-dimensional bench-scale combustion system. Reburning effectiveness for initial levels ranging from 600 to 650 ppm is evaluated. It is found that for Shenhua bituminous coal, NOx reduction performance of superfine pulverized coal owns its unique advantage, 50% higher than conventional particle size. Medium reburning fuel fraction (RF20 similar to RF25) and low oxygen concentration are recommended to be ensured in this experiment. The yield of HCN and CH4 along the furnace axis does not seem to be decisive on the effect of particle size, but is closely related to the effect of reburning fuel fraction. Both exhaust and in-flame measurements are reported in this paper to provide valuable experimental data for practical engineering applications. (C) 2014 Elsevier Ltd. All rights reserved.