氧化钙孔隙参数对固硫反应速率的影响  

Effect of CaO pore parameters on desulfurization reaction rates

作　　者：曹立勇[1] 何榕[1] 

机构地区：[1]清华大学热能工程系,热科学与动力工程教育部重点实验室,北京100084

出　　处：《清华大学学报（自然科学版）》2010年第2期283-286,共4页Journal of Tsinghua University(Science and Technology)

基　　金：国家自然科学基金资助项目(50676048);国家“九七三”重点基础研究项目(2006CB200305)

摘　　要：为研究孔隙结构对固硫特性的影响,采用随机行走方法从分子运动理论的角度建立了多孔颗粒中的气体扩散模型。用简单碰撞理论来模拟气固反应,运用Fick扩散定律来模拟钙离子在产物层中的扩散。在不同温度和不同二氧化硫体积分数下进行数值模拟,研究了反应条件及孔隙参数对固硫速率的影响。结果表明,在固硫过程第一阶段,固硫速率与温度关系符合Arrhenius方程,与反应气体体积分数成线性关系;固硫速率受颗粒的孔隙率及比表面积的影响规律不明显,而与分形维数的指数成线性关系。To study the influence of the porous media structure on desulfurization, a random walk method used to simulate fractal porous media and gas diffusion in porous media was modeled with the classic kinetic theory of gases, using simple collision theory （SCT） to simulate the gas-solid reaction and Fick＇s law to describe the ion diffusion in the product layer. The reaction rate was predicted for various temperatures and S02 volume fraction. The results show that in the first sulfation stage, the relation between the reaction rate and the temperature is consistent with the Arrhenius equation and that the reaction rate increases linearly with SOs volume fraction. The logarithm of the reaction rates decreases linearly with the fractal dimensions of the models and the porosity and specific surface area have little influence on the reaction rate.

关 键 词：固硫 反应速率 孔隙参数 分形维数 气体扩散 

分 类 号：X511[环境科学与工程—环境工程]