【摘要】 为深入了解反应结晶过程中碳酸铈颗粒的分散特性,采用CFD软件模拟DTB结晶器内固-液两相和液-液两相混合过程。考察固-液两相混合过程中,碳酸铈颗粒的剪切速率分布和浓度分布,对反应结晶器进行优化,最终选取了两个进料口位置在桨叶上方附近、桨叶距离底面高度为H/3、离底悬浮搅拌转速为425 r/min的最佳操作条件。进而分析液-液两相混合反应生成碳酸铈的过程,模拟结果表明,适当增加搅拌速度可以增大反应区域、增加颗粒粒度的均匀性;反应物料CeCl₃质量分数为0.3,NH₃HCO₃质量分数为0.4时,生成的碳酸铈颗粒粒度分布较均匀。更多还原

【Abstract】 In order to understand the dispersion characteristics of cerium carbonate particles during reactive crystallization,the mixing process of solid- liquid and liquid- liquid phases were simulated in the DTB crystallizer with the CFD software. In the solid- liquid mixing process,shear rate distribution and concentration distribution of cerium carbonate particles were investigated to optimize the crystallizer. Finally,two feed positions are selected close to the blade,the height of blade is H /3 from bottom,and suspension stirring speed is 425 rpm. Based on the above best operation conditions,the reactive process of cerium carbonate was analyzed. The simulation results show that the reaction region and the particle size uniformity can be increased by increasing the stirring speed appropriately. When the mass fraction of reactant CeCl₃ is 0. 3 and NH₄HCO₃ is 0. 4,the size distribution of cerium carbonate particle is the most uniform.更多还原