结晶成核与生长两阶段的模型识别研究

The Study on Model Identification of Nucleation and Crystal Growth Stages

针对溶液间歇结晶过程的特点 ,定义并关联了无因次变量K和K ,用于对结晶过程中成核和生长两阶段进行定量识别。对于添加晶种的KNO3 —H2 O间歇结晶过程 ,模拟分析的结果表明 :无因次变量K和K 的数值均随着晶核形成过程而减小 ,随着晶核生长过程而增大。由实验测定的动态透光率和溶液浓度 ,即可对结晶过程中的成核和生长两阶段进行定量识别。

Two new zero dimension variables,K and K *,concerning the stage identification of solution batch crystallization process were defined in this paper.For seeded crystallization of potassium nitrate in water,the results calculated showed the values of K and K * would be decreased with nucleation process and increased with crystal growth process.Based on the characteristics of the variables,coupled with the dynamic transmittance and concentration data,the nucleation and crystal growth stages could be identified.