Investigation on Nitrogen Chemistry Modeling in Coal Combustion Process with CPD Calculation

This paper presents a model that combines the CPD model to predict coal pyrolysis and a nitrogen chemistry model to calculate NOx emissions from coal combustion process. The model saves the need to obtain the pyrolysis components of coal by experimental means while ensuring the accuracy of the calculation results to a certain extent. The model is validated by comparison with experimental results from the literature on coal pyrolysis cases and coal combustion cases with non-staging, fuel staging, as well as air staging. In general, the modeling results for the three combustion cases are satisfactory, except for the deviation of the results for NO in the case of some small air ratios at air staging combustion, which leads to some limitations of the model. While according to the reported studies, in the actual process, the small air ratio values are not in the optimal conditions for air staging combustion, making the model of some practical significance. In the future, more work is needed in solving the calculations of coal combustion processes at low air ratios to further refine the model.