Abstract: Effect of biochemical sludge （BS） from a coal chemical enterprise in Xinjiang on CO₂ gasification performance of Heishan coal （HSC） was systematically investigated. The chemical composition and structure characteristics of BS and HSC were analyzed by proximate analysis, ultimate analysis and infrared analysis. Thermogravimetric behavior, CO₂ gasification reactivity and gasification kinetics of BS, HSC and their mixture （BS∶HSC=0.2∶1） were analyzed by TG–DTG and Coats-Redfern model. Results showed that BS contains high volatile （54.31%） and ash （36.31%）, and the surface functional group is dominated by —OH stretching vibration of alcohols or phenols, indicating that BS is rich in organic components, which can provide carbon source for gasification process. By CO₂ gasification performance test, at 970~1000 ℃, the carbon conversion rate of the mixed sample is always higher than that of HSC alone. The weight loss of co-gasification is 54.85%, which is 26.38% higher than that of HSC （43.40%）. During the gasification reaction, the co-gasification conversion rate of the mixed sample is always higher than that of Heishan coal, and the activation energy of the gasification reaction is reduced from 1 027.20 kJ/mol to 650.34 kJ/mol by kinetic analysis. Compared with HSC gasification alone, the activation energy is reduced by 36.69%. It shows that the blending of BS can significantly improve carbon conversion and gasification rate, reduce activation energy, and shows a well synergistic effect, which provides a theoretical basis for the resource utilization of biochemical sludge.