Relationship between chemical components and coal ash deposition through the DTF experiments using real-time weight measurement system

The chemical components of ash in coal are important factors affecting the ash deposition in the entrained-flow gasification process. Most previous research aimed at investigating pertinent chemical components affecting ash deposition has focused on the deposited sample after experiments without consideration of the time frame to verify the relationship between ash chemical components and deposition. However, this study examined the relation of the chemical components to the ash deposition by using the drop tube furnace (DTF), in which a real-time weight measurement (RWM) system had been installed. The RWM system, capable of recording the amount of deposited ash per second, was specifically developed for this work. Three pulverized coal samples, in the range of bituminous and sub-bituminous coal, were employed in the DTF experiments to compare the relationship between the ash chemical components and deposition. It was found that the ash deposition behavior in a real-time was related to the presence of Fe and Ca components, and high concentrations of these components tended to increase the deposition rate. The ash deposition could be diverse by maintaining or decreasing the Fe and Ca components, which are responsible for fouling growth.