Effect of CO₂ concentration on the release of NO from char combustion in cement precalciner

 The release of NO from coal char combustion under the atmosphere of different CO₂ concentrations was investigated in a high temperature gas-solid reactor with suspension and spray. The effects of temperature and cement raw meal on the release of NO under different CO₂ concentrations were discussed. The results indicate that with the increase of CO₂ concentration, the rate of NO release, the peak value of NO concentration and the percent conversion of char-N to NO decrease. The percent conversion of char-N to NO greatly rises due to the catalysis of cement raw meal, while the catalysis of the cement raw meal becomes weakening with the increase of CO₂ concentration. It is also found that the conversion of char-N to NO increases with the rise of temperature. However, the effect of temperature on the NO release reduces with the increase of CO₂ concentration.