SCI和EI收录∣中国化工学会会刊

Chinese Journal of Chemical Engineering ›› 2020, Vol. 28 ›› Issue (6): 1504-1513.DOI: 10.1016/j.cjche.2020.03.024

• Fluid Dynamics and Transport Phenomena • Previous Articles     Next Articles

Determining axial dispersion coefficients of pilot-scale annular pulsed disc and doughnut columns

Xiong Yu1, Han Zhou1, Qiang Zheng1, Shan Jing1, Wenjie Lan2, Shaowei Li1,3   

  1. 1 Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084, China;
    2 State Key Laboratory of Heavy Oil Processing, China University of Petroleum(Beijing), Beijing 102249, China;
    3 State Key Laboratory of Chemical Engineering, Tsinghua University, Beijing 100084, China
  • Received:2019-10-16 Revised:2020-03-03 Online:2020-07-29 Published:2020-06-28
  • Contact: Shan Jing, Shaowei Li
  • Supported by:
    We gratefully acknowledge the support of the National Natural Science Foundation of China(21776151 and 21576147) for this investigation.

Determining axial dispersion coefficients of pilot-scale annular pulsed disc and doughnut columns

Xiong Yu1, Han Zhou1, Qiang Zheng1, Shan Jing1, Wenjie Lan2, Shaowei Li1,3   

  1. 1 Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084, China;
    2 State Key Laboratory of Heavy Oil Processing, China University of Petroleum(Beijing), Beijing 102249, China;
    3 State Key Laboratory of Chemical Engineering, Tsinghua University, Beijing 100084, China
  • 通讯作者: Shan Jing, Shaowei Li
  • 基金资助:
    We gratefully acknowledge the support of the National Natural Science Foundation of China(21776151 and 21576147) for this investigation.

Abstract: In this study, a computational fluid dynamics (CFD) method was adopted to calculate axial dispersion coefficients of annular pulsed disc and doughnut columns (APDDCs). Passive tracer was uniformly injected by pulse input at the continuous phase inlet, and its concentration governing equation was solved in liquid-liquidtwo-phase flow fields. The residence time distributions (RTDs) were obtained using the surface monitoring technique. The adopted RTD-CFD method was verified by comparing the axial dispersion coefficient between simulation and experimental results in the literature. However, in pilot-scale APDDCs, the axial dispersion coefficients predicted by the CFD-RTD method were approximately three times larger than experimental results determined by the steady-state concentration profile method. This experimental method was demonstrated to be insensitive to the variation of the axial dispersion coefficient. The CFD-RTD method was more recommended to determine the axial dispersion coefficient. It was found that the axial dispersion coefficient increased with an increase in pulsation intensity, column diameter, and plate spacing, but was little affected by the throughput.

Key words: Axial dispersion, Computational fluid dynamics, Residence time distribution, Annular-pulsed disc and doughnut column

摘要: In this study, a computational fluid dynamics (CFD) method was adopted to calculate axial dispersion coefficients of annular pulsed disc and doughnut columns (APDDCs). Passive tracer was uniformly injected by pulse input at the continuous phase inlet, and its concentration governing equation was solved in liquid-liquidtwo-phase flow fields. The residence time distributions (RTDs) were obtained using the surface monitoring technique. The adopted RTD-CFD method was verified by comparing the axial dispersion coefficient between simulation and experimental results in the literature. However, in pilot-scale APDDCs, the axial dispersion coefficients predicted by the CFD-RTD method were approximately three times larger than experimental results determined by the steady-state concentration profile method. This experimental method was demonstrated to be insensitive to the variation of the axial dispersion coefficient. The CFD-RTD method was more recommended to determine the axial dispersion coefficient. It was found that the axial dispersion coefficient increased with an increase in pulsation intensity, column diameter, and plate spacing, but was little affected by the throughput.

关键词: Axial dispersion, Computational fluid dynamics, Residence time distribution, Annular-pulsed disc and doughnut column