Influence of impeller diameter on overall gas dispersion properties in a sparged multi-impeller stirred tank

doi:10.1016/j.cjche.2014.11.030

Chinese Journal of Chemical Engineering ›› 2015, Vol. 23 ›› Issue (6): 890-896.DOI: 10.1016/j.cjche.2014.11.030

Influence of impeller diameter on overall gas dispersion properties in a sparged multi-impeller stirred tank

Yuyun Bao, Bingjie Wang, Mingli Lin, Zhengming Gao, Jie Yang

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

收稿日期:2014-05-09 修回日期:2014-11-08 出版日期:2015-06-28 发布日期:2015-07-09
通讯作者: Jie Yang
基金资助:
Supported by the National Natural Science Foundation of China (21121064, 21206002, 21376016).

Influence of impeller diameter on overall gas dispersion properties in a sparged multi-impeller stirred tank

Yuyun Bao, Bingjie Wang, Mingli Lin, Zhengming Gao, Jie Yang

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

Received:2014-05-09 Revised:2014-11-08 Online:2015-06-28 Published:2015-07-09
Contact: Jie Yang
Supported by:
Supported by the National Natural Science Foundation of China (21121064, 21206002, 21376016).

摘要/Abstract

摘要： The impeller configuration with a six parabolic blade disk turbine below two down-pumping hydrofoil propellers, identified as PDT + 2CBY, was used in this study. The effect of the impeller diameter D, ranging from 0.30T to 0.40T (T as the tank diameter), on gas dispersion in a stirred tank of 0.48 m diameter was investigated by experimental and CFD simulation methods. Power consumption and total gas holdup were measured for the same impeller configuration PDT + 2CBY with four different D/T. Results show that with D/T increases from 0.30 to 0.40, the relative power demand (RPD) in a gas–liquid system decreases slightly. At low superficial gas velocity V_S of 0.0078 m·s^-1, the gas holdup increases evidently with the increase of D/T. However, at high superficial gas velocity, the systemwith D/T=0.33 gets a good balance between the gas recirculation and liquid shearing rate, which resulted in the highest gas holdup among four different D/T. CFD simulation based on the two-fluid model along with the Population Balance Model (PBM) was used to investigate the effect of impeller diameter on the gas dispersion. The power consumption and total gas holdup predicted by CFD simulation were in reasonable agreement with the experimental data.

关键词: Gas holdup, Mixing, Multiphase reactors, Relative power demand, CFD, Multi-impeller stirred tank

Abstract: The impeller configuration with a six parabolic blade disk turbine below two down-pumping hydrofoil propellers, identified as PDT + 2CBY, was used in this study. The effect of the impeller diameter D, ranging from 0.30T to 0.40T (T as the tank diameter), on gas dispersion in a stirred tank of 0.48 m diameter was investigated by experimental and CFD simulation methods. Power consumption and total gas holdup were measured for the same impeller configuration PDT + 2CBY with four different D/T. Results show that with D/T increases from 0.30 to 0.40, the relative power demand (RPD) in a gas-liquid system decreases slightly. At low superficial gas velocity V_S of 0.0078 m·s^-1, the gas holdup increases evidently with the increase of D/T. However, at high superficial gas velocity, the systemwith D/T=0.33 gets a good balance between the gas recirculation and liquid shearing rate, which resulted in the highest gas holdup among four different D/T. CFD simulation based on the two-fluid model along with the Population Balance Model (PBM) was used to investigate the effect of impeller diameter on the gas dispersion. The power consumption and total gas holdup predicted by CFD simulation were in reasonable agreement with the experimental data.

Key words: Gas holdup, Mixing, Multiphase reactors, Relative power demand, CFD, Multi-impeller stirred tank

Yuyun Bao, Bingjie Wang, Mingli Lin, Zhengming Gao, Jie Yang. Influence of impeller diameter on overall gas dispersion properties in a sparged multi-impeller stirred tank[J]. Chinese Journal of Chemical Engineering, 2015, 23(6): 890-896.

参考文献

[1] Z.M. Gao, Y.C.Wang, L.T. Shi, J.F. Fu, Theoretical and experimental studies on bubble diameter and gas holdup in aerated stirred tanks, Chin. J. Chem. Eng. 4 (1996) 283-289.

[2] D. Birch, N. Ahmed, Gas sparging in vessels agitated by mixed flow impellers, Powder Technol. 88 (1996) 33-38.

[3] M. Cooke, P.J. Heggs, Advantages of the hollow (concave) turbine for multi-phase agitation under intense operating conditions, Chem. Eng. Sci. 60 (2005) 5529-5543.

[4] Y.Y. Bao, L. Chen, Z.M. Gao, J.F. Chen, Local void fraction and bubble size distributions in cold-gassed and hot-sparged stirred reactors, Chem. Eng. Sci. 65 (2010) 976-984.

[5] S.D. Shewale, A.B. Pandit, Studies inmultiple impeller agitated gas-liquid contactors, Chem. Eng. Sci. 61 (2006) 489-504.

[6] P. Davide, M. Franco, Analysis of the fluid dynamic behavior of the liquid and gas phases in reactors stirred with multiple hydrofoil impellers, Ind. Eng. Chem. Res. 39 (2000) 3202-3211.

[7] Y.Y. Bao, L. Chen, Z.M. Gao, X.N. Zhang, J.M. Smith, N.F. Kirkby, Temperature effects on gas dispersion and solid suspension in a three-phase stirred reactor, Ind. Eng. Chem. Res. 47 (2008) 4270-4277.

[8] Y.Y. Bao, X.N. Zhang, Z.M. Gao, L. Chen, J.F. Chen, J.M. Smith, N.F. Kirkby, Gas dispersion and solid suspension in a hot sparged multi-impeller stirred tank, Ind. Eng. Chem. Res. 47 (2008) 2049-2055.

[9] Z.M. Gao, L.T. Shi, Effect of temperature on gas hold-up in aerated stirred tanks, Chin. J. Chem. Eng. 11 (2003) 204-207.

[10] A.D. Harvey, S.P. Wood, D.E. Leng, Experimental and computational study of multiple impeller flows, Chem. Eng. Sci. 52 (1997) 1479-1491.

[11] W.J. Wang, Z.S.Mao, Numerical simulation of gas-liquid flow in a stirred tankwith a Rushton impeller, Chin. J. Chem. Eng. 10 (2002) 385-395.

[12] G.L. Lane, M.P. Schwarz, G.M. Evans, Numerical modeling of gas-liquid flow in stirred tanks, Chem. Eng. Sci. 60 (2005) 2203-2214.

[13] A. Bakker, H.A. Akker, A computational model for the gas-liquid flow in a stirred vessel, Chem. Eng. Res. Des. 72 (1994) 594-606.

[14] Q.H. Zhang, Y.M. Yong, Z.S. Mao, C. Yang, C.J. Zhao, Experimental determination and numerical simulation of mixing time in a gas-liquid stirred tank, Chem. Eng. Sci. 64 (2009) 2926-2933.

[15] A.R. Khopkar, P.A. Tanguy, CFD simulation of gas-liquid flows in stirred vessel equipped with dual Rushton turbines: Influence of parallel, merging and diverging flow configurations, Chem. Eng. Sci. 63 (2008) 3810-3820.

[16] J. Min, Y.Y. Bao, L. Chen, Z.M. Gao, J.M. Smith, Numerical simulation of gas dispersion in an aerated stirred reactor with multiple impellers, Ind. Eng. Chem. Res. 47 (2008) 7112-7117.

[17] Y. Sato, K. Sekoguchi, Liquid velocity distribution in two-phase bubble flow, Int. J. Multiphase Flow 2 (1975) 79-95.

[18] A.R. Khopkar, A.R. Rammohan, V.V. Ranade, M.P. Dudukovic, Gas-liquid flow generated by a Rushton turbine in stirred vessel: CARPT/CT measurements and CFD simulations, Chem. Eng. Sci. 60 (2005) 2215-2229.

[19] R. Clift, J.R. Grace, M.E. Weber, Bubbles, Drops, and Particles, Dover Publications, 2005.

[20] M. Lopez de Bertodano, R.T. Lahey Jr., O.C. Jones, Phase distribution in bubbly twophase flows in vertical ducts, Int. J. Multiphase Flow 20 (1994) 805-818.

[21] H. Luo, H.F. Svendsen, Theoretical model for drop and bubble breakup in turbulent dispersions, AIChE J. 42 (1996) 1225-1233.

[22] M.J. Prince, H.W. Blanch, Bubble coalescence and break-up in air-sparged bubble columns, AIChE J. 36 (1990) 1485-1499.

[23] W.B. Li, Experimental Investigation of Micromixing and Macromixing in a Multiphase Stirred Tank(Ph.D. Thesis) Beijing University of Chemical Technology, Beijing, 2013. (in Chinese).

[24] W.B. Li, X.Y. Geng, Y.Y. Bao, Z.M. Gao, Micromixing characteristics in a gas-liquid- solid stirred tank with settling particles, Chin. J. Chem. Eng. 23 (2015) 461-470.

Influence of impeller diameter on overall gas dispersion properties in a sparged multi-impeller stirred tank

Influence of impeller diameter on overall gas dispersion properties in a sparged multi-impeller stirred tank

PDF (PC)

可视化

摘要/Abstract

引用本文

使用本文

参考文献

相关文章 15

编辑推荐

Metrics

本文评价

[1]	Chaojie Li, Xianxin Fang, Meiling Sun, Jihai Duan, Weiwen Wang. Study on two-phase cloud dispersion from liquefied CO₂ release[J]. 中国化学工程学报, 2023, 60(8): 37-45.
[2]	Lijuan Zhao, Zhe Tan, Xiaoguang Zhang, Qijun Zhang, Wei Wang, Qiang Deng, Jie Ma, De'an Pan. Research on process modeling and simulation of spent lead paste desulfurization enhanced reactor[J]. 中国化学工程学报, 2023, 60(8): 293-303.
[3]	Mingzhi Li, Zhikai Liu, Wang Yao, Chao Xu, Yangping Yu, Mei Yang, Guangwen Chen. Ultrasonic cavitation-enabled microfluidic approach toward the continuous synthesis of cesium lead halide perovskite nanocrystals[J]. 中国化学工程学报, 2023, 59(7): 32-41.
[4]	Wenting Fan, Fang Zhao, Ming Chen, Jian Li, Xuhong Guo. An efficient microreactor with continuous serially connected micromixers for the synthesis of superparamagnetic magnetite nanoparticles[J]. 中国化学工程学报, 2023, 59(7): 85-91.
[5]	Abdelgadir Bashir Banaga, Yan-Bin Li, Zhi-Hao Li, Bao-Chang Sun, Guang-Wen Chu. Experimental investigation of the mixing efficiency via intensity of segregation along axial direction of a rotating bar reactor[J]. 中国化学工程学报, 2023, 59(7): 153-159.
[6]	Junhao Wang, Shugang Ma, Peng Chen, Zhipeng Li, Zhengming Gao, J. J. Derksen. Mixing of miscible shear-thinning fluids in a lid-driven cavity[J]. 中国化学工程学报, 2023, 58(6): 112-123.
[7]	Hongwei Liang, Wenling Li, Zisheng Feng, Jianming Chen, Guangwen Chu, Yang Xiang. Numerical simulation of gas-liquid flow in the bubble column using Wray-Agarwal turbulence model coupled with population balance model[J]. 中国化学工程学报, 2023, 58(6): 205-223.
[8]	Jiajia Chen, Xinyu Lu, Dandan Wang, Pengcheng Xiu, Xiaoli Gu. Effective depolymerization of alkali lignin using an attapulgite-Ce_0.75Zr_0.25O₂(ATP-CZO)-supported cobalt catalyst in ethanol/isopropanol media[J]. 中国化学工程学报, 2023, 57(5): 50-62.
[9]	Chengang Yang, Huaizhi Han, Quan Zhu, Xiangyuan Li. Cracking and buoyancy effect on hydrocarbon endothermic and heat transfer characteristics in rectangular mini-channel[J]. 中国化学工程学报, 2023, 56(4): 242-254.
[10]	Shuangfei Zhao, Yingying Nie, Wenyan Zhang, Runze Hu, Lianzhu Sheng, Wei He, Ning Zhu, Yuguang Li, Dong Ji, Kai Guo. Microfluidic field strategy for enhancement and scale up of liquid–liquid homogeneous chemical processes by optimization of 3D spiral baffle structure[J]. 中国化学工程学报, 2023, 56(4): 255-265.
[11]	Tian Zhang, Qingshan Huang, Shujun Geng, Aqiang Chen, Yan Liu, Haidong Zhang. Impacts of solid physical properties on the performances of a slurry external airlift loop reactor integrating mixing and separation[J]. 中国化学工程学报, 2023, 55(3): 1-12.
[12]	Qi Han, Xin-Yuan Zhang, Hai-Bo Wu, Xian-Tai Zhou, Hong-Bing Ji. Different efficiency toward the biomimetic aerobic oxidation of benzyl alcohol in microchannel and bubble column reactors: Hydrodynamic characteristics and gas–liquid mass transfer[J]. 中国化学工程学报, 2023, 55(3): 84-92.
[13]	Songsong Wang, Hong Li, Changyuan Tao, Renlong Liu, Yundong Wang, Zuohua Liu. Study on cavern evolution and performance of three mixers in agitation of yield-pseudoplastic fluids[J]. 中国化学工程学报, 2023, 55(3): 111-122.
[14]	Tianpeng LiZhou, Jiajia Luo, Tiefeng Wang. Enhancement of acetylene and ethylene yields in partially decoupled oxidation of ethane by changing the composition of heat carrier[J]. 中国化学工程学报, 2022, 47(7): 71-78.
[15]	Liying Chen, Junheng Guo, Wenpeng Li, Shuchun Zhao, Wei Li, Jinli Zhang. A numerical study of mixing intensification for highly viscous fluids in multistage rotor–stator mixers[J]. 中国化学工程学报, 2022, 47(7): 218-230.