Gas dispersion and solid suspension in a three-phase stirred tank with triple impellers

doi:10.1016/j.cjche.2019.09.013

Chinese Journal of Chemical Engineering ›› 2020, Vol. 28 ›› Issue (5): 1195-1202.DOI: 10.1016/j.cjche.2019.09.013

• Fluid Dynamics and Transport Phenomena • Next Articles

Gas dispersion and solid suspension in a three-phase stirred tank with triple impellers

Hanbin Wang, Zhengming Gao, Bingjie Wang, Yuyun Bao, Ziqi Cai

State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029, China

Received:2019-04-05 Revised:2019-09-21 Online:2020-07-29 Published:2020-05-28
Contact: Yuyun Bao, Ziqi Cai
Supported by:
The authors gratefully acknowledge the financial support from the National Key R&D Program of China (2017YFB0306703), the Fundamental Research Funds for the Central Universities (XK1802-1), and the National Natural Science Foundation of China (No. 21676007).

Gas dispersion and solid suspension in a three-phase stirred tank with triple impellers

Hanbin Wang, Zhengming Gao, Bingjie Wang, Yuyun Bao, Ziqi Cai

State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029, China

通讯作者: Yuyun Bao, Ziqi Cai
基金资助:
The authors gratefully acknowledge the financial support from the National Key R&D Program of China (2017YFB0306703), the Fundamental Research Funds for the Central Universities (XK1802-1), and the National Natural Science Foundation of China (No. 21676007).

Abstract

Abstract: The hydrodynamics is still not fully understood in the three-phase stirred tank equipped with multi-impeller due to the intensive interaction between phases. In this work, the solid critical suspension speed (N_JSG), relative power demand (RPD) and overall gas holdup (ε_G) were measured in an air-water-glass beads stirred tank equipped with multi-impeller, which consists of a parabolic blade disk turbine below two down-pumping hydrofoils. Results show that either the N_JSG or the specific power consumption increases when increasing the volumetric solid concentration or superficial gas velocity. RPD changes less than 10% when solid volumetric concentration ranges from 0 to 15%. ε_G decreases with the increase of solid concentration, and increases with the increase of both superficial gas velocity and the total specific power consumption. The quantitative correlations of N_JSG, RPD and ε_G were regressed as the function of superficial gas velocity, specific power consumption, Froude number and gas flow number, in order to provide the reference in the design of such three-phase stirred tank with similar multi-impellers.

Key words: Solid suspension, Gas holdup, Gas-liquid-solid system, Stirred reactor

摘要： The hydrodynamics is still not fully understood in the three-phase stirred tank equipped with multi-impeller due to the intensive interaction between phases. In this work, the solid critical suspension speed (N_JSG), relative power demand (RPD) and overall gas holdup (ε_G) were measured in an air-water-glass beads stirred tank equipped with multi-impeller, which consists of a parabolic blade disk turbine below two down-pumping hydrofoils. Results show that either the N_JSG or the specific power consumption increases when increasing the volumetric solid concentration or superficial gas velocity. RPD changes less than 10% when solid volumetric concentration ranges from 0 to 15%. ε_G decreases with the increase of solid concentration, and increases with the increase of both superficial gas velocity and the total specific power consumption. The quantitative correlations of N_JSG, RPD and ε_G were regressed as the function of superficial gas velocity, specific power consumption, Froude number and gas flow number, in order to provide the reference in the design of such three-phase stirred tank with similar multi-impellers.

关键词: Solid suspension, Gas holdup, Gas-liquid-solid system, Stirred reactor

Hanbin Wang, Zhengming Gao, Bingjie Wang, Yuyun Bao, Ziqi Cai. Gas dispersion and solid suspension in a three-phase stirred tank with triple impellers[J]. Chinese Journal of Chemical Engineering, 2020, 28(5): 1195-1202.

Hanbin Wang, Zhengming Gao, Bingjie Wang, Yuyun Bao, Ziqi Cai. Gas dispersion and solid suspension in a three-phase stirred tank with triple impellers[J]. 中国化学工程学报, 2020, 28(5): 1195-1202.

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Gas dispersion and solid suspension in a three-phase stirred tank with triple impellers

Gas dispersion and solid suspension in a three-phase stirred tank with triple impellers

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