絮凝过程的群体平衡模型研究进展

Population balance model for the flocculation process: a research review

回顾了群体平衡模型(Population Balance Model,PBM)应用于絮凝过程中絮体粒经分布模型的相关研究,主要包括区间离散法求解PBM,絮体聚并模型和破碎模型等。近年来,描述聚并效率的"曲线模型",与Kol-mogorov尺度相关的破碎频率模型,絮体的分形特征等方面得到了较大的进展。但絮凝过程动力学的研究还并不完善,絮体粒径的动力学演变过程还需要更多的研究。未来的研究应集中于:(1)更多的实验验证,尤其是絮体破碎行为的测定;(2)结合絮凝机理,提出更有效的絮体聚并、破碎模型;(3)更合理的流体剪切力描述。

The researches on the population balance model(PBM) applied to the flocculation process for simulating floc size distribution are reviewed.The researches include the discretisation techniques for solving PBM,the expressions for aggregation and breakage kinetics and so on.In recent years,the development in this area is great,such as the 'curvilinear model' for describing collision efficiency,the breakage frequency model related to Kolmogorov microscale,the floc fractal character,etc.However,the researches on the flocculation dynamics and the evolutionary process of floc size distribution are not perfect.In future,we should do more experiments to verify the floc breakage behavior,provide more efficient aggregation and breakage kernel models and offer more reasonable description of velocity gradients.