磷石膏-氨-水固碳反应体系氨浓度对石膏颗粒溶解速率的影响  

Effect of ammonia concentration on dissolution rate of gypsum particles in phosphogypsum-ammonia-water reaction system for carbon sequestration

作　　者：吴林 李季[1] 朱家骅[1] 宫源 葛敬[1] WU Lin;LI Ji;ZHU Jiahua;GONG Yuan;GE Jing(School of Chemical Engineering,Sichuan University,Chengdu 610065,Sichuan,China)

机构地区：[1]四川大学化学工程学院,四川成都610065

出　　处：《化工学报》2020年第8期3575-3584,共10页CIESC Journal

基　　金：国家科技支撑计划项目(2013BAC12B01)。

摘　　要：磷石膏-氨-水固碳反应体系中石膏颗粒的溶解,是三相流化矿化反应系统的控制性步骤。在氨水溶液中石膏颗粒能与氨分子形成N—H…O氢键,导致石膏溶解速率受氨浓度影响。基于已知粒度分布的石膏颗粒群在不同氨浓度下的溶解实验数据,采用种群平衡模型与物料衡算相结合的方法,探究了氨浓度对石膏颗粒群溶解特性的影响规律。结果表明:氨浓度的增加会降低石膏溶解速率,随着溶解的进行,氨对溶解的抑制作用会减弱。此外,随着氨浓度的增大,增加单位氨浓度石膏溶解速率的降幅将变小。结合实验数据拟合关联溶解动力学参数,构建了氨浓度影响下石膏的溶解速率模型,预测了三相流化矿化反应系统中两个串联回路石膏料浆所需的停留时间,为磷石膏-氨-水固碳反应体系矿化烟气CO2的放大设计提供了理论依据。The dissolution of gypsum particles in the phosphogypsum-ammonia-water carbon fixation reaction system is a controlling step of the three-phase fluidized mineralization reaction system.The macroscopic dissolution rate was infected by ammonia concentrations because the N—H···O hydrogen bonds between the gypsum surface and ammonia molecules were formed in the ammonia solution.Dissolution data of gypsum particle group with certain particle size distribution were experimentally determined under different ammonia concentrations.The influence regulations of ammonia concentration on gypsum particle group dissolution characteristics were investigated combining with the population equilibrium model and the material balance method.The results indicated that the dissolution rate of gypsum reduced with increase of ammonia concentration.As the gypsum dissolution processing,the dissolution inhibition of gypsum by ammonia has been weakened.Besides,the decrease of gypsum dissolution rate would be smaller with the increase of ammonia concentration.The dissolution rate model of gypsum under different ammonia concentration were established by fit the dissolution dynamics parameters based on experimental data,and to predict the residence time required in two series loops in the TFMS,which provides theoretical support for scale up design of the phosphogypsum-ammonia-water carbon fixation system mineralizing flue gas CO2.

关 键 词：氨 石膏 种群平衡 溶解 速率模型 

分 类 号：TQ021.4[化学工程]