Abstract: Ashing method and temperature have significant influences on the ash compositions of solid fuel. However，there are few studies on the ash characteristics of residual carbon and its blends with bituminous coal affected by ashing method. In the exploration on the influence of different ashing methods and temperatures on the ash physicochemical characteristics of coal-based solid fuel blends，the focus laid on the impact of the traditional ash preparation method（815 ℃）and the lowtemperature plasma ashing method（＜200 ℃）on physicochemical characteristics and reaction mechanisms of the ash generated from coal-based solid-fuel blends. The experimental results show that low-temperature ash of all samples，except residual carbon of coal − water − slurry gasification，has a large weight loss peak in 400-600 ℃ ，which is due to the combustion process of the incomplete oxidized organic matter in the low-temperature ash. The main difference between high-temperature ash and low-temperature ash is their formations of Ca element . The Ca in high-temperature ash mainly exists in the form of CaSO4，while that in low-temperature ash is of various forms，such as CaS and CaCO3. Iron element exists as FeS2 in low-temperature ash，while mainly exists in the form of Fe2O3 in high-temperature ash. The interaction of minerals in different fuels should be taken into account when ash samples characteristics of the blends after co-combustion are evaluated. The research is conductive to deepen the understanding of the ashing behaviors in the blending and burning process of solid fuels，and promote the large-scale，efficient and secure utilization of gasification residual carbon.

Key words: blending and burning, ashing method, element distribution, crystal phase, low-temperature plasma ashing, Zaoquan bituminous coal, residual carbon