石灰石直接脱硫反应动力学参数的求解  

The calculation of kinetic parameters for direct desulphurization of limestone

作　　者：王松岭[1] 尚建宇[1] 冯垚飞[1] 张合明[1] 

机构地区：[1]华北电力大学能源动力与机械工程学院,河北保定071003

出　　处：《华北电力大学学报（自然科学版）》2012年第2期84-87,共4页Journal of North China Electric Power University：Natural Science Edition

基　　金：国家自然科学基金资助项目(50606009)

摘　　要：利用热重分析仪在四种不同的温度下进行了石灰石直接脱硫实验,得到了各温度下脱硫反应的钙转化率及反应速率,采用未反应收缩核模型,根据阿伦尼乌斯定律拟合计算了化学反应控制阶段的化学反应速率常数和产物层扩散控制阶段的产物层扩散系数与温度的数量关系。结果表明:两个反应阶段活化能分别为85.751 kJ/mol,141.529 kJ/mol,直接脱硫反应从化学反应控制阶段向产物层控制阶段过渡时活化能逐渐增大,较低温度下,硫化反应完全由产物层扩散控制;温度较高时,硫化反应则由化学反应和产物层扩散二者共同控制,这是因为与产物层扩散控制相比,由化学反应控制时的活化能更低的缘故。Thermal gravimetric analysis was used in direct desulphurization of limestone at 4 different temperatures to get calcium conversion and reaction rate,in addition,unreacted shrinking core model was adopted as mathematical model when calculating the relationship between rate constant of chemical reaction phase,diffusional constant of product layer phase,and temperature with the help of Arrhennius Law.The results showed that the activation energy of two different phases are 85.751 KJ/mol,141.529 KJ/mol respectively.The activation energy of desulfurization was increasing when reaction transited from chemical reaction phase to product layer phase.Product-layer diffusion was dominated in lower temperature reaction,while higher temperature reaction was controlled by chemical reaction and product-layer diffusion for the sake of the lower activation energy of chemical reaction.

关 键 词：石灰石 脱硫 缩核反应模数 扩散系数 产物层 

分 类 号：TK019[动力工程及工程热物理]