摘要
Based on the population balance equation in a batch crystallizer characteristic of seeded precipitation, a model to calculate the rate of apparent crystal growth of aluminum hydroxide from the size distribution was deve- loped. The simulation results indicate that the rate of apparent crystal growth during seeded precipitation exhibits a manifest dependence on the crystal size. In general, there is an obvious increase in the apparent crystal growth rate with the augment in crystal size. The apparent activation energy increases with the increase of characteristic crystal size, which indicates that the growth of small crystals is controlled by surface chemical reaction; it is gradually controlled by both the surface reaction and diffusion with the augment in crystal size.
Based on the population balance equation in a batch crystallizer characteristic of seeded precipitation, a model to calculate the rate of apparent crystal growth of aluminum hydroxide from the size distribution was developed. The simulation results indicate that the rate of apparent crystal growth during seeded precipitation exhibits a manifest dependence on the crystal size. In general, there is an obvious increase in the apparent crystal growth rate with the augment in crystal size. The apparent activation energy increases with the increase of characteristic crystal size, which indicates that the growth of small crystals is controlled by surface chemical reaction; it is gradually controlled by both the surface reaction and diffusion with the augment in crystal size.
基金
Project(50274076)supportedbytheNationalNaturalScienceFoundationofChina
关键词
铝酸钠溶液
晶体生长速率
动力学
炼铝
sodium aluminate solutions seeded precipitations
aluminum hydroxides
apparent crystal growth rates
kinetics
