Co-Gasification of Cow Manure and Bituminous Coal: A Study on Reactivity, Synergistic Effect, and Char Structure Evolution

As special waste biomass, cow manure (CM) is also the main pollutant in agricultural production. The combination of cow manure and coal is conducive to the sustainable development of energy and the solution to pollution problems. This work aims to investigate the co-gasification reactivity and synergy of cow manure and Meihuajing (MHJ) bituminous coal blends at 800-1100 °C using a thermogravimetric analyzer, and the correlation between char gasification reactivity and its structural characteristics is performed. The results indicate that the sensitivity of gasification reactivity to temperature is gradually weakened with the proportion of CM increasing. The synergistic effect on reactivity was observed in the co-gasification process of CM/MHJ. The addition of CM promoted the synergistic effect obviously at the low carbon conversion level, and the inhibitory effect with the CM addition on the order degree of char carbon structure was enhanced during the co-gasification process according to Raman spectroscopy analysis. The addition of CM promoted the porous structure evolutions, which make the pore size distribution and the specific surface developed remarkable. The changes in carbon and pore structures can be well related to the gasification reactivity. The findings in this study would be helpful in the understanding of the co-gasification synergy mechanism of cow manure and coal blends.