The effect of biomass addition on pyrolysis characteristics and gas emission of coal gangue by multi-component reaction model and TG-FTIR-MS

Abstract The pyrolysis experiment of biomass added to coal gangue was studied by thermogravimetric-Fourier transform infrared spectroscopy-mass spectrometry (TG-FTIR-MS) method. The multi-component reaction model was used to simulate the pyrolysis reaction of coal gangue and biomass. The most suitable model was obtained, and the pyrolysis mechanism was analyzed. According to the two-component reaction model of CG pyrolysis, the decomposition temperature range of components in CG is 340–800 °C and 400–620 °C. The five-component reaction model can well simulate the pyrolysis process of coal gangue and biomass. Meanwhile, the effects of different proportions of biomass in the mixture on the gas products of coal gangue pyrolysis were analyzed. It was found that the addition of biomass to coal gangue could promote the release of gaseous organic matter during pyrolysis. CG75PS25 only has a synergistic effect in the high temperature zone greater than 600 °C. CG25PS75 only has a synergistic effect in a small range of 230–300 °C, and there is an inhibitory effect in other temperature ranges. In general, there is an inhibitory effect between coal gangue and biomass on CO2 formation, which is of positive significance for greenhouse gas emission reduction.