Melting Characteristics of Coal Ash and Properties of Fly Ash to Understand the Slag Formation in the Shell Gasifier
Hui Wang, Lihua Cheng, Jianglong Pu, Jigang Zhao
Abstract
under high temperatures, inhibit the formation of mullite, and thus decrease the ash FT. The coal ash FT was found to have a good linear relation with the ash compositions, which can sever as a reference to the coal blending. According to the model parameters, it is shown that Mg has the most significant promoting effect on the decrease in FT of the coal ash. The caking tendency of fly ash increases with the rising Ca content and an excessive Ca-based fluxing agent used in the coal blending will lead to the aggregation of the Ca-rich clasts around the fly ash particle, resulting in the plugging of the waste heat boiler in the gasifier. Therefore, the Mg-based fluxing agent is more promising to improve the ash fusion performance and reduce the caking tendency of the coal fly ash.