摘要
煤灰分中主要矿物质之间的反应对灰分特性有着重要影响。本文在具有温控的小型高温反应器中对粉煤灰和复合添加剂所组成的混合灰样进行了静态煅烧试验 ,并对煅烧后的灰样进行了X射线衍射分析 (XRD) ,着重讨论了温度和时间以及复合添加剂量对灰分矿相组成特性的影响。试验结果表明 :当温度低于 1 2 0 0℃时 ,灰分中主要是游离态的氧化物和部分新生成的矿物如钙黄长石、硅酸二钙 ;当温度在 1 2 0 0℃～ 1 30 0℃时 ,灰分中的主要矿物是钙黄长石 ,当温度在 1 32 0℃～ 1 350℃时 ,灰分主要矿物是硅酸二钙 ,同时存在一定量的硅酸三钙、铝酸三钙、铁铝酸四钙以及硫铝酸钙。随着灰分中氧化钙的含量增加 ,高碱性矿物含量逐渐增大 ,同时高温下加热持续时间过长 ,部分新生成的矿物将发生分解。
Mineral reactions in the inorganic compositions of coal ash have important effect on the ash characteristic In this paper, a small scale high temperature reactor was used to calcine coal ash blended with compound additives, and the burnt ash was analyzed by X ray powder diffraction (XRD) Moreover, The influences of temperature, residence time, and additives quantity on mineral characteristics have been discussed The result indicated that the ash contained some free oxides and newly forming minerals such as gehlenite and dicalcium silicate below 1?200?℃; when the firing temperature ranged from 1?200?℃ to 1?300?℃, the major mineral was gehlenite; as the temperature reached between 1?320?℃ and 1?350?℃,the minerals were principally composed of dicalcium silicate and other minerals such as tricalcium silicate, tricalcium aluminate, calcium aluminoferrite and calcium aluminosulfate As the content of CaO in the ash increases, the high alkalinity minerals increase gradually; also it is found that some newly formed minerals may decompose in long heat up time at high temperature
出处
《燃料化学学报》
EI
CAS
CSCD
北大核心
2002年第4期306-310,共5页
Journal of Fuel Chemistry and Technology
基金
国家自然科学基金 ( 50 176 0 15)
教育部骨干教师计划 ( 2 2 0 2 )~~
