Emission Control of NO and SO2 for the High-Temperature and Low O2 Concentration Combustion of Coke by Urea and NH4HCO3

Urea and NH4HCO3 were used to control the emission of NO and SO2 from the combustion of coke at high-temperature and low oxygen concentration. Urea and NH4HCO3 could control NO emission only under 1100°C. Their effects disappeared above 1100°C even though the increase of urea and NH4HCO3 content from 10  to  50  wt  %. However, they showed good desulfurization effect on the emission of SO2 at all combustion temperatures and their effects showed remarkable results even at 1500°C. Only 10  wt  % of urea or NH4HCO3 could control the emission of SO2 effectively at 1400 and 1500°C. This effect was caused by ·NH and ·NH2 from the thermal decomposition of reducing agents at high temperature. Low O2 concentration showed little effect on the removal of SO2. Ammonia slip from the thermal decomposition of reducing chemical was not a considerable level.