Study of Combustion Characteristics and Matching Between the Blends of Gasification Fine Slag and Coal with Varied Ranks

Gasification fine slag (GS) is a kind of solid waste produced in the process of coal gasification. Due to its high annual production and large accumulation, it is potentially harmful to air quality and groundwater, and has certain impact on human health, so resource utilization of coal gasification slag is an urgent problem at present. Combustion is considered as a cost-effective way for GS utilization. In this paper, the combustion characteristics and fuel matching of GS mixed with different coalification degree coal (lignite, bituminous coal, anthracite) were studied. The combustion of three kinds of mixed fuels was analyzed by thermogravimetric data, conventional combustion characteristic parameters, activation energy and statistical principal component analysis (PCA). The kinetic analysis shows that the co-combustion with coal effectively reduces the activation energy of GS, and the activation energy increases with the increase of coalification degree. The results of PCA analysis show that with the increase of coalification degree, the matching of mixed fuel is improved, and the low rank coal is mainly affected by the addition ratio, while the influence of the heating rate of high rank coal is more significant. The results of this study can provide some guidance for the co-combustion of GS.