静态颗粒堆积下碳酸钙的热分解特性及反应动力学研究  

Study on thermal decomposition characteristics and reaction kinetics of calcium carbonate under particle accumulation

作　　者：李维 陶从喜 王浩 李世界 何明海 梁乾 蒋文伟 陈义强 王明 Li Wei;Tao Congxi;Wang Hao;Li Shijie;He Minghai;Liang Qian;Jiang Wenwei;Chen Yiqiang;Wang Ming(China Resources Cement Technology Research and Development(Guangxi)Co.,Ltd,Nanning 530409;China Resources Cement(Fengkai)Co.,Ltd)

机构地区：[1]华润水泥技术研发(广西)有限公司,广西南宁530409 [2]华润水泥(封开)有限公司,广西封开526599

出　　处：《新世纪水泥导报》2024年第5期9-15,I0001,共8页Cement guide for new epoch

摘　　要：为了探究不同升温速率、不同CO_(2)浓度气氛条件下碳酸钙热分解特性及动力学反应机理,采用静态堆积形式对碳酸钙进行热分解实验研究。研究表明,提高升温速率会对碳酸钙分解产生促进作用;随着CO_(2)浓度由40%提升至80%,气相中CO_(2)平衡分压不断上升,若要使碳酸钙发生热分解反应需逐渐向高温段迁移;采用Coats-Redfern积分法拟合碳酸钙热分解机理函数,发现在较低CO_(2)浓度阶段,碳酸钙主要遵循随机成核和随后生长模型规律,计算分解活化能约为23.65 kJ·mol,而当CO_(2)浓度上升至60%~80%以后,化学反应控制转变为基于收缩球体的三维相边界反应模型,分解活化能分别为128.04 kJ·mol、140.56 kJ·mol。以上研究揭示了在高CO_(2)浓度下碳酸钙分解特征,为解决水泥行业碳捕集问题提供了实验基础和理论依据。The article conducted an experimental study on the thermal decomposition of calcium carbonate using a static stacking method,mainly exploring the characteristics and kinetic reaction mechanism of calcium carbonate thermal decomposition under different heating rates and different CO_(2)concentration conditions.The study showed that increasing the heating rate would promote the decomposition of calcium carbonate;as the CO_(2)concentration increased from 40%to 80%,the equilibrium partial pressure of CO_(2)in the gas phase continue rised,and if the thermal decomposition reaction of calcium carbonate was to occur,it would need to gradually migrate to higher temperature segments;using the Coats Redfern integral method to fit the thermal decomposition mechanism function of calcium carbonate,it was found that at lower CO_(2)concentration stages,calcium carbonate mainly followed the random nucleation and subsequent growth model law,and the calculated decomposition activation energy was approximately 23.65 kJ mol.However,when the CO_(2)concentration increased to 60%to 80%,the chemical reaction control shifted to a three-dimensional phase boundary reaction model based on shrinking spheres,with decomposition activation energies of 128.04 kJ-mol and 140.56 kJ-mol,respectively.The above research reveals the characteristics of calcium carbonate decomposition at high CO_(2)concentrations,providing experimental and theoretical basis for solving the carbon capture problem in the cement industry.

关 键 词：碳酸钙 升温速率 CO_(2)浓度 分解动力学 

分 类 号：TQ172.11[化学工程—水泥工业]