CO2(g)-NH3(aq)-Ca2+(aq)两相体系中碳酸钙晶体生长动力学模型  

Kinetic model of calcium carbonate crystal growth in CO2(g)-NH3(aq)-Ca2+(aq) two-phase system

作　　者：范晓宇 葛敬[1] 朱家骅[1] 夏素兰[1] FAN Xiaoyu;GE Jing;ZHU Jiahua;XIA Sulan(School of Chemical Engineering,Sichuan University,Chengdu 610065,China)

机构地区：[1]四川大学化学工程学院,四川成都610065

出　　处：《磷肥与复肥》2020年第12期4-8,共5页Phosphate & Compound Fertilizer

基　　金：国家科技支撑计划课题(2013BAC12B01)。

摘　　要：二氧化碳直接矿化磷石膏联产碳酸钙工艺过程可以看作是磷石膏溶解过程与碳酸钙结晶过程的耦合。为避免磷石膏溶解过程的包覆现象,选取氯化钙为钙源,从理论与实验两方面对碳酸钙结晶生长过程进行研究,基于种群平衡模型及MeCabe'sOl定律假设,建立296.15~323.15 K内碳酸钙晶体线性生长速率G与溶液过饱和度S之间的关系:G=6.0×103μm·(L/g)1.27·min-1exp(-31929J/mol/RT)s1.27.碳酸钙生长活化能为31.93kJ/m.对比文献值可判断碳酸RT钙晶体生长速率受表面反应控制。The process of direct mineralizing phosphogypsum to produce calcium carbonate can be regarded as the integration of phosphogypsum dissolution and calcium carbonate crystallization.In order to avoid the coating of calcium carbonate on the surface of phosphogypsum particles,calcium chloride is selected as the calcium source.The crystallization growth process of calcium carbonate is studied theoretically and experimentally,based on the population balance model and the assumption of McCabe’s Δ L law,the relationship between the linear growth rate G and the supersaturation S of calcium carbonate crystal in the temperature of 296.15-323.15 K is established:G=6.0×103μm·(L/g)1.27·min-1exp(-31929J/mol/RT)s1.27..The growth activation energy of calcium carbonate is 31.93 kj/mol,which can be judged that the growth rate of calcium carbonate is controlled by surface reaction.

关 键 词：碳酸钙 结晶生长 速率 种群平衡 

分 类 号：TQ132.32[化学工程—无机化工] O781[理学—晶体学]