Development and validation of a gas-phase reduced mechanism for pulverized coal ignition and combustion

A gas-phase reduced reaction mechanism has been developed for pulverized coal combustion. The reduction process was performed in flue gas environments of 1200–1800 K and 5 %–40 % O₂, using Reaction Workbench and CHEMKIN-Pro. The resulting reduced mechanism, consisting of 27 species and 58 reactions (27S58R), incorporates key C₂ species while preserving the primary reaction pathways from GRI-Mech 3.0 mechanism. The predictive performance of the 27S58R mechanism, in terms of ignition delay time, temperature, and species concentrations, was initially validated against GRI-Mech 3.0 data using CHEMKIN-Pro. Subsequently, a pulverized coal ignition and combustion model incorporating the 27S58R mechanism was verified against online experimental results from a flat-flame entrained-flow coal reactor. This numerical model successfully predicted the experimental data and their trends. The 27S58R mechanism accurately predicted the heterogeneous ignition mode for anthracite, and the homo-heterogeneous ignition mode for bituminous coal and lignite at 1800 K and 20 % O₂. Moreover, the prediction accuracy surpasses that of the 12S10R mechanism (Yuan et al., 2024). Overall, the 27S58R mechanism effectively balances the predictive accuracy and computational cost, making it well-suited for the simulating practical pulverized coal combustion scenarios. It is expected to provide reference value in pulverized coal numerical simulations.