燃煤过程中元素Na和Fe在可吸入颗粒物中的形态与分布  

Research on Morphology and Distribution of Na and Fe in Inhalable Particles, Formed During Combustion of Coal

作　　者：刘小伟[1] 徐明厚[1] 于敦喜[1] 郝炜[1] 隋建才[1] 俞云[1] 

机构地区：[1]华中科技大学煤燃烧国家重点实验室,武汉430074

出　　处：《动力工程》2005年第5期719-723,共5页Power Engineering

基　　金：国家重点基础研究(2002CB211602);国家自然科学基金(50325621)

摘　　要：通过对平顶山烟煤在沉降炉内的燃烧试验，结合热力学平衡计算分析，研究了两种选定的矿物质成灰元素Na和Fe在可吸入颗粒物中的形态与分布。燃烧试验条件为：煤粉粒径小于63Mm，燃烧温度在1400℃，炉内燃烧气氛为空气气氛。试验采用低压撞击器（LPI）按不同粒径大小从0．03～10μm共分为13级，分别采集燃烧后的可吸入颗粒物。并采用热力学平衡计算分析方法研究了氧化性气氛中元素Na和Fe的化学形态和物理相。试验和计算结果显示：钠元素主要以Na单质的形式气化，大部分以NaO、Na2SO4、NaCl、Na3PO4的形式存在于亚微米颗粒中，极少量以NaAlSi3O8相存在于PM1.0-10中；Fe元素主要以FeO的形式气化，部分以Fe2O3的形式存在于亚微米颗粒中，部分以Fe3O4和Fe2O3的形式存在于PM1.0-10中。The morphology and distribution of two particularly chosen elements, Na and Fe, contained in inhalable dust particles, were studied with the help of thermodynamic analysis of combustion experiments performed with Pingdingshan bituminous coal in a drop-tube furnace. The conditions of the experiments were： coal particle of sizes below 63μm, combustion temperature 1 400℃, combustion atmosphere in the furnace being air. Inhalable particles within the range of 0.03 - 10μm were collected, in 13 sizings after combustion, with a low pressure impactor （LPI）. The chemical morphology and physical phase of the Na and Fe in an oxidizing atmosphere were studied by thermodynamic equilibrum analysis methods. Test results show that： Na mainly vaporizes in the elemental state; in sub-micro particles it exists mainly in the form of NaO, Na2SO4, NaCI and Na3 PO, with but a tiny amount existing as NaAISi30s phase in PM1.0-1.0 The element Fe evaporates mainly in the form of FeO; part of it existing in sub-micro particles in the form of Fe2O3, while another part in PM1.0-1.0 in the form of Fe3O, and Fe2O3 . Fig 1, tables 2 and refs 6.

关 键 词：环境工程学 燃煤 颗粒物 钠 铁 形态与分布 

分 类 号：X5[环境科学与工程—环境工程]