Modeling Nitrogen Release during Devolatilization on the Basis of Chemical Structure of Coal

A model that predicts the amount and distribution between tar and light gas of nitrogen released during devolatilization has been developed and incorporated into the chemical percolation devolatilization (CPD) model. This work represents the first volatile nitrogen release model developed on the basis of 13 C NMR measurements of coal structure. This work also represents the first volatile nitrogen release model evaluated by comparing model predictions with chemical structural features of the char (determined by 13 C NMR spectral analyses). The model is limited to nitrogen release during primary pyrolysis, and assumes that all light-gas nitrogen is HCN. Model predictions of nitrogen release compare well with measured values for most coals and devolatilization conditions tested.