Size distributions of major elements in residual ash particles from coal combustion

作     者：YU DunXi XU MingHou YAO Hong LIU XiaoWei 

作者机构：State Key Laboratory of Coal Combustion Huazhong University of Science and Technology Wuhan 430074 China 

出 版 物：《Chinese Science Bulletin》 (中国科学通报)

年 卷 期：2009年第54卷第6期

页      面：958-964页

核心收录：

学科分类：081702[工学-化学工艺] 07[理学] 08[工学] 0817[工学-化学工程与技术] 0703[理学-化学] 

基　　金：Supported by the National Natural Science Foundation of China (Grant Nos. 50706013  50721005 & 50720145604) 

主　　题：煤燃烧过程 粉煤灰颗粒 粒度分布 剩余 燃烧实验 微量元素 沉积模式 大小分布 

摘      要：Combustion experiments for three coals of different ranks were conducted in an electrically-heated drop tube furnace. The size distributions of major elements in the residual ash particles (0.4μm) such as Al, Si, S, P, Na, Mg, K, Ca and Fe were investigated. The experimental results showed that the con-centrations of Al and Si in the residual ash particles decreased with decreasing particle size, while the concentrations of S and P increased with decreasing particle size. No consistent size distributions were obtained for Na, Mg, K, Ca and Fe. The established deposition model accounting for trace element dis-tributions was demonstrated to be applicable to some major elements as well. The modeling results indicated that the size distributions of the refractory elements, Al and Si, were mainly influenced by the deposition of vaporized elements on particle surfaces. A dominant fraction of S and P vaporized during coal combustion. Their size distributions were determined by surface condensation, reaction or adsorption. The partitioning mechanisms of Na, Mg, K, Ca and Fe were more complex.