CIESC Journal ›› 2019, Vol. 70 ›› Issue (10): 3932-3940.DOI: 10.11949/0438-1157.20190533

• Fluid dynamics and transport phenomena • Previous Articles     Next Articles

Study on mixing and settling characteristics in mixer-settler

Yuxin WU(),Qiao TANG,Jiyizhe ZHANG,Yundong WANG()   

  1. State Key Laboratory of Chemical Engineering, Department of Chemical Engineering, Tsinghua University, Beijing 100084, China
  • Received:2019-05-21 Revised:2019-08-30 Online:2019-10-05 Published:2019-10-05
  • Contact: Yundong WANG

混合澄清槽混合与澄清特性的规律研究

吴雨馨(),唐巧,张姬一哲,王运东()   

  1. 清华大学化学工程系,化学工程联合国家重点实验室,北京 100084
  • 通讯作者: 王运东
  • 作者简介:吴雨馨(1996—),女,博士研究生,wuyuxin18@ mails.tsinghua.edu.cn
  • 基金资助:
    国家自然科学基金项目(21636004);国家安全学术基金项目(U1530107)

Abstract:

Mix-settler is the earliest extraction equipment which is still widely used at present. This paper studies on mixing and settling characteristics in a mixer-settler according to the limitation. The research process uses the SOPAT droplet measurement platform to measure the droplet size. The relationship between the droplet size distribution, the average droplet size, the liquid holding capacity, the size of the dispersion belt and the entrainment amount of different system mixing chambers, clarification chambers is discussed. The results show that Sauter diameter of droplet, D 32, is linear with the agitation speed. D 32 and liquid holdup were satisfied with the Calderbank model in the mixing chamber. And in the settling chamber, the settling performance was mainly affected by droplet size, organic/aqueous phase density difference, viscosity, mass transfer, temperature and interfacial tension. The drop studies will lay the foundation for optimizing or improving the structure of the mixer-settler.

Key words: mixer-settler, SOPAT measurement platform, drop diameter, extraction, equilibrium, interfacial tension

摘要:

混合澄清槽是最早也是目前依然被广泛使用的萃取设备,针对混合澄清槽存在的局限性对其混合与澄清特性进行规律性研究。研究过程采用SOPAT液滴测量平台测量液滴尺寸,针对不同体系混合室、澄清室液滴尺寸分布、平均液滴粒径、持液量、分散带尺寸、夹带量之间的关系探讨达到研究目的。实验结果表明,在混合过程中,大部分体系的等比表面积平均直径D 32与转速呈指数关系,与持液量的关系符合Calderbank模型。而在澄清过程中,澄清效果主要受到液滴尺寸、密度差、黏度、质量传递、温度、界面张力的影响,其中界面张力的增加会增强分相效果。通过对液滴测量影响因素进行系统的研究,为具体的操作下优化或改进混合澄清槽的结构打下基础。

关键词: 混合澄清槽, SOPAT测量平台, 液滴尺寸, 萃取, 平衡, 界面张力

CLC Number: