Synergetic effects during co-pyrolysis of woody biomass and Zhundong coal

Co-pyrolysis of biomass and coal is a promising way to produce liquid and char products while contributing to reduce CO2 emission. The co-pyrolysis behaviors and characteristics of poplar sawdust (PS) with Zhundong coal (ZD) in the different blending ratios were investigated using a thermogravimetry analyzer in this work. The results indicated that compared with ZD, PS had a lower characteristic temperature of volatile matter release and a stronger pyrolysis reactivity. There were synergistic promoting and inhibiting effects in the whole co-pyrolysis process of PS and ZD, which were related to the blending ratio. The PS addition percentage of 20%, 40%, and 80% into ZD presented the obvious positive synergistic interactions in the co-pyrolysis process, enhancing the thermal decomposition rate of volatile compounds. The important kinetic parameters were obtained using the first-order reaction model. Adding PS into ZD in the pyrolysis process changed the porous structure and surface morphology of ZD char particles. The results obtained are expected to be helpful in the equipment design and practical application of biomass and ZD co-pyrolysis.