Effect of Micronized Coal Reburning on NOX Reduction

Micronized coal reburning is one of the most effective de-NO_X technologies for its high NO_X reduction efficiency and low operating cost. By numerical simulation and experimental study, NO_X reduction efficiency influenced by the temperature and stoichiometric ratio in rich zone, the velocity and the particle size of reburning fuel during the coal reburning process in a one dimension furnace has been investigated. The results indicate that the optimum temperature and stoichiometric ratio in rich zone is about 1200°C and 0.9 respectively. NO_X reduction efficiency will increase with the velocity of reburning fuel increased and particle size decreased. The optimum particle size of reburning fuel is 20μm. Compared with conventional coal reburning, micronized coal reburning is superior not only because it has less influence on combustion efficiency but also for its higher NO_X reduction efficiency.