Study on the preparation and physicochemical property evolution of waste wood chips/bituminous coal-based composite fuel

In response to the "carbon peak and carbon neutrality" demands of the steel industry, this study employs the co-micro carbonization of waste wood chips and bituminous coal to prepare carbon-based composite fuels. By regulating the mixing ratios (from 9:1 to 5:5) and carbonization temperatures (300–500 °C), the pyrolysis behavior, combustion characteristics, and physicochemical evolution are systematically analyzed. The results indicate that mixing waste wood chips with bituminous coal significantly improves the pyrolysis synergy. When the proportion of bituminous coal increases to 60 %, the activation energy of rapid pyrolysis decreases from 130.07 kJ mol⁻¹ to 46.94 kJ mol⁻¹. The solid yield increases from 28.81 % to 45.47 % as the proportion of bituminous coal increases, but when the carbonization temperature rises to 500 °C, the yield decreases to 41.03 % due to intensified volatile release. Carbonization at 500 °C promotes the formation of a porous structure in the composite fuel and enhances the condensation degree of the aromatic carbon network. The Raman spectroscopy I_D/I_G value increases to 2.793, indicating that the increase in defect sites is beneficial for the combustion reaction.