The Effect Of Coal Ash Melting Regulation On Mineral Transformation

The coal resource will still play a dominant role in domestic energy industry in the future. In terms of utilization of coal, it is indispensable to study the coal ash fusion characters. In general, pow plants’boilers to avoid slagging demand the coal transported into furnace with higher ash fusion temperature. While the entrained-flow coal gasifier in order to discharge the slag have a strict requirement on ash fusion. Traditionally, the coal with lower ash fusion temperatures (AFTs) is better. Therefore, it is necessary to adopt diverse methods to regulate AFTs to cater to different industrial requirements.This thesis chose the Zhungeer coal and Zhundong coal as the experimental resource, which both have a large reserve in China and are used widely. Blend the two kind of coals getting five synthetic coals in order of different blending ratio. The AFTs have been measured respectively. The blended ash AFTs pattern illustrated the figures were in a downward trend, then in a upward trend. The X-ray diffraction (XRD) technology and FactSage calculating soft package were used to research the ash mineral transformation occurred in heating progress, to reveal the cause leading the trend. The analysis result found several important eutectic melting (EM). It’s the EM appearing and disappearing progress increases the liquid phase in ash slag causing the ash melting. The quantity of mines constructing the EM is responsible for the mineral melting degree, and have a series of effects on other mines.Current regulations of AFTs are all according to the element compositions. While the predicting based on element compositions normally is not too precise and widely adapted. By blending and adding additive, the article studied several ash samples with a similar element compositions to investigate the internal reason. Although these ash samples’element compositions are same, their AFTs still exist big difference. The XRD and scanning electron microscope combined with Energy Dispersive X-ray Detector (SEM-EDX) were used to undertake the further study. The experimental consequence indicate that there are two factors determining the AFTs. Not only the primary chemical elements, but also the the occurrence in minerals of chemical elements play the important role in coal ash ATFs.