煤燃烧过程中CaO-HF固氟反应动力学机理  

Kinetic mechanics of thereaction between CaO and HF during coal combustion

作　　者：王宏伟[1] 齐庆杰[1] 王继仁[1] 刘建忠[2] 周俊虎[2] 岑可法[2] 

机构地区：[1]辽宁工程技术大学安全科学与工程学院,辽宁阜新123000 [2]浙江大学热能工程研究所,浙江杭州310027

出　　处：《煤炭学报》2014年第1期161-165,共5页Journal of China Coal Society

基　　金：国家自然科学基金资助项目(50474032);辽宁省高等学校计划资助项目(L201104)

摘　　要：为了揭示钙基吸收剂燃烧固氟机理，提高固氟效率，建立了CaO-HF固氟反应的未反应收缩核动力学模型，通过模型计算，分析了反应温度、HF气体浓度、CaO粒径及添加量对固氟反应特性的影响，并与实验结果进行了对比。结果表明：未反应收缩核模型可较好地描述CaO—HF固氟反应的宏观动力学，预测反应温度、HF气体浓度及CaO颗粒粒径对化学反应的影响。CaO转化率随反应温度和反应时间的增加而增加，但在1073～1273K范围内，反应温度的提高对CaO转化率的提高幅度不是很大；CaO转化率随HF气体浓度的增加而增加，与反应温度的影响相比．HF气体浓度对固氟反应影响更为明显。随CaO初始粒径的减小，CaO转化率显著提高，CaO初始粒径对固氟反应速度有显著的影响。The CaO-HF reaction of coal combustion process is the main chemical reaction process of calcium-based flu- orine retention. Un-reacted shrinking core dynamic model of CaO-HF on fluorine-retention reaction was established to reveal the mechanism of the combusting calcium-based fluorine retention agent of fluorine retention and improve the effect of fluorine retention, thus promoting the development and application of combustion fluorine retention technolo- gy. Calculated through the model, the reaction temperature, HF gas concentration, CaO particle size and the additive amount of the fluorine-fixing were investigated. The results show that un-reacted shrinking core model can be used to describe the macro-dynamics of chemical CaO-HF fluorine retention reaction, to forecast the reaction temperature, HF concentration and how CaO particle size and additive amount affect the reaction. The conversion of CaO increases with the increasing of reaction temperature and reaction time. However, reaction temperature doesn＇ t have much effect on CaO conversion when temperature ranges from 1 073 K to 1 273 K ; CaO conversion increases with the increasing of HF concentration and the effect of fluorine retention is more obvious comparing with that of reaction temperature. With the decrease of the initial particle size of CaO, CaO concentration rate has significantly improved, that＇ s to say, the initial particle size of CaO has a significantly impact on the rate of fluorine retention.

关 键 词：煤燃烧 钙基固氟剂 CaO-HF固氟反应 动力学 

分 类 号：TQ534.9[化学工程—煤化学工程]