Different rotation speeds: A novel approach to enhancing chaos and mixing efficiency in multi-shaft stirred reactors

doi:10.1016/j.cjche.2025.04.024

中国化学工程学报 ›› 2025, Vol. 87 ›› Issue (11): 239-251.DOI: 10.1016/j.cjche.2025.04.024

Different rotation speeds: A novel approach to enhancing chaos and mixing efficiency in multi-shaft stirred reactors

Shuang Qin^1,2, Tong Meng^1,2,3, Yu Wang^1,2, Yundong Wang⁴, Changyuan Tao^1,2, Qian Zhang¹, Bing Li⁵, Zuohua Liu^1,2

1. School of Chemistry and Chemical Engineering, Chongqing University, Chongqing 400044, China;
2. State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing 400044, China;
3. Department of Industrial Chemistry "TosoMontanari", University of Bologna, 40131 Bologna, Italy;
4. Department of Chemical Engineering, Tsinghua University, Beijing 100084, China;
5. School of Chemistry and Chemical Engineering, Yangtze Normal University, Chongqing 408100, China

收稿日期:2025-03-18 修回日期:2025-04-28 接受日期:2025-04-29 出版日期:2025-11-28 发布日期:2025-07-03
通讯作者: Zuohua Liu,E-mail:liuzuohua@cqu.edu.cn
基金资助:
This work was supported by the National Natural Science Foundation of China (22078030, 52021004), National Key Research and Development Project (2019YFC1905802), Key Project of Independent Research Project of State Key Laboratory of Coal Mine Disaster Dynamics and Control (2011DA105287-zd201902), Chongqing Natural Science Foundation Innovation and Development Joint Fund Project (CSTB2022NSCQ-LZX0014), Hubei Three Gorges Laboratory Open/Innovation Fund (SK211009, SK215001), and Fundamental Research Funds for Central Universities (2022CDJQY-005). At the same time, this work also received funding from the China Scholarship Council.

Different rotation speeds: A novel approach to enhancing chaos and mixing efficiency in multi-shaft stirred reactors

Shuang Qin^1,2, Tong Meng^1,2,3, Yu Wang^1,2, Yundong Wang⁴, Changyuan Tao^1,2, Qian Zhang¹, Bing Li⁵, Zuohua Liu^1,2

1. School of Chemistry and Chemical Engineering, Chongqing University, Chongqing 400044, China;
2. State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing 400044, China;
3. Department of Industrial Chemistry "TosoMontanari", University of Bologna, 40131 Bologna, Italy;
4. Department of Chemical Engineering, Tsinghua University, Beijing 100084, China;
5. School of Chemistry and Chemical Engineering, Yangtze Normal University, Chongqing 408100, China

Received:2025-03-18 Revised:2025-04-28 Accepted:2025-04-29 Online:2025-11-28 Published:2025-07-03
Contact: Zuohua Liu,E-mail:liuzuohua@cqu.edu.cn
Supported by:
This work was supported by the National Natural Science Foundation of China (22078030, 52021004), National Key Research and Development Project (2019YFC1905802), Key Project of Independent Research Project of State Key Laboratory of Coal Mine Disaster Dynamics and Control (2011DA105287-zd201902), Chongqing Natural Science Foundation Innovation and Development Joint Fund Project (CSTB2022NSCQ-LZX0014), Hubei Three Gorges Laboratory Open/Innovation Fund (SK211009, SK215001), and Fundamental Research Funds for Central Universities (2022CDJQY-005). At the same time, this work also received funding from the China Scholarship Council.

摘要/Abstract

摘要： In response to the accelerating demands of industrial development, the scale-up of stirred reactors has become increasingly prevalent. Multi-shaft stirred reactors have emerged as a promising solution; however, a critical challenge remains in achieving efficient mixing while simultaneously minimizing energy consumption. Here, a novel approach based on differential rotation speeds to optimize mixing performance was proposed. Results demonstrate that a carefully configured rotation speed difference significantly enhances mixing efficiency, reducing mixing time by 17.89% and power consumption by 12.07%. This strategy not only amplifies flow field instability but also minimizes instability discrepancies, promoting a more uniform distribution of vortices across various scales. Furthermore, under this approach, the bottom impeller has the strongest impact on mixing, while the middle and lower impellers synergistically strengthen the weaker mixing regions and facilitate the redistribution of energy in the flow field. This method promotes efficient energy transfer from large-scale to small-scale vortices, ultimately improving overall mixing performance. This work offers a promising avenue for the optimal design and operation of multi-shaft stirred reactors, advancing both efficiency and energy sustainability.

关键词: Multi-shaft stirred reactors, Rotation speeds difference, Chaos characterization, Mixing efficiency, Flow field instability

Abstract: In response to the accelerating demands of industrial development, the scale-up of stirred reactors has become increasingly prevalent. Multi-shaft stirred reactors have emerged as a promising solution; however, a critical challenge remains in achieving efficient mixing while simultaneously minimizing energy consumption. Here, a novel approach based on differential rotation speeds to optimize mixing performance was proposed. Results demonstrate that a carefully configured rotation speed difference significantly enhances mixing efficiency, reducing mixing time by 17.89% and power consumption by 12.07%. This strategy not only amplifies flow field instability but also minimizes instability discrepancies, promoting a more uniform distribution of vortices across various scales. Furthermore, under this approach, the bottom impeller has the strongest impact on mixing, while the middle and lower impellers synergistically strengthen the weaker mixing regions and facilitate the redistribution of energy in the flow field. This method promotes efficient energy transfer from large-scale to small-scale vortices, ultimately improving overall mixing performance. This work offers a promising avenue for the optimal design and operation of multi-shaft stirred reactors, advancing both efficiency and energy sustainability.

Key words: Multi-shaft stirred reactors, Rotation speeds difference, Chaos characterization, Mixing efficiency, Flow field instability

Shuang Qin, Tong Meng, Yu Wang, Yundong Wang, Changyuan Tao, Qian Zhang, Bing Li, Zuohua Liu. Different rotation speeds: A novel approach to enhancing chaos and mixing efficiency in multi-shaft stirred reactors[J]. 中国化学工程学报, 2025, 87(11): 239-251.

参考文献

[1] S.A.F. Leite, B.S. Leite, D.J.O. Ferreira, B.E.L. Baeta, J.V.H. Dangelo, The effects of agitation in anaerobic biodigesters operating with substrates from swine manure and rice husk, Chem. Eng. J. 451 (2023) 138533.
[2] J.Y. Dong, Y.L. Wu, X.C. Liu, C.K. Zhang, S.M. Wang, J. Wen, CFD-PBE simulation of para-xylene crystallization behavior and process amplification under different operating conditions, Ind. Eng. Chem. Res. 62 (36) (2023) 14657-14670.
[3] Y.R. Wang, Q. Yang, Y.N. Du, H.Q. Chen, Evaluation of the impact of stirring on the formation, structural changes and rheological properties of ovalbumin fibrils, Food Hydrocoll. 128 (2022) 107615.
[4] F. Scargiali, A. Brucato, G. Micale, A. Tamburini, On the reduction of power consumption in vortexing unbaffled bioslurry reactors, Ind. Eng. Chem. Res. 59 (16) (2020) 8037-8045.
[5] G.Y. Shang, K. Cui, W.F. Cai, X.N. Hu, P.K. Jin, K. Guo, A 20 L electrochemical continuous stirred-tank reactor for high rate microbial electrosynthesis of methane from CO₂, Chem. Eng. J. 451 (2023) 138898.
[6] G.D. Zhang, X.Y. Shi, F. Wang, Methane hydrate production using a novel spiral-agitated reactor: Promotion of hydrate formation kinetics, AIChE. J. 68 (1) (2022) e17423.
[7] E. Villermaux, Mixing versus stirring, Annu. Rev. Fluid Mech. 51 (2019) 245-273.
[8] P.E. Dimotakis, Turbulent mixing, Annu. Rev. Fluid Mech. 37 (2005) 329-356.
[9] L. Torrente-Murciano, J.B. Dunn, P.D. Christofides, J.D. Keasling, S.C. Glotzer, S.Y. Lee, K.M. Van Geem, J. Tom, G.H. He, The forefront of chemical engineering research, Nat. Chem. Eng. 1 (1) (2024) 18-27.
[10] E.K. Nauha, O. Visuri, R. Vermasvuori, V. Alopaeus, A new simple approach for the scale-up of aerated stirred tanks, Chem. Eng. Res. Des. 95 (2015) 150-161.
[11] P. Vrabel, R.G.J.M. van der Lans, K.C.A.M. Luyben, L. Boon, A.W. Nienow, Mixing in large-scale vessels stirred with multiple radial or radial and axial up-pumping impellers: modelling and measurements, Chem. Eng. Sci. 55 (23) (2000) 5881-5896.
[12] M.T. Castro, J.D. Ocon, Novel designs of blade mixer impellers from the discrete element method and topology optimization, Chem. Eng. J. 490 (2024) 151863.
[13] T.A. Wyrobnik, S. Oh, A. Ducci, M. Micheletti, Engineering characterization of the novel Bach impeller for bioprocessing applications requiring low power inputs, Chem. Eng. Sci. 252 (2022) 117263.
[14] B. Delacroix, L. Fradette, F. Bertrand, B. Blais, Which impeller should be chosen for efficient solid-liquid mixing in the laminar and transitional regime? AIChE. J. 67 (11) (2021) e17360.
[15] C. Sirasitthichoke, S. Salloum, P.M. Armenante, Power number and hydrodynamic characterization of a stirred vessel equipped with a Retreat-Blade Impeller and different types of pharmaceutical single baffles, Chem. Eng. Sci. 257 (2022) 117725.
[16] T. Wang, H. Yu, R. Xiang, X.M. Chen, X. Zhang, Performance and unsteady flow characteristic of forward-curved impeller with different blade inlet swept angles in a pump as turbine, Energy 282 (2023) 128890.
[17] J. Stelmach, C. Kuncewicz, T. Jirout, F. Rieger, Mixing tank hydrodynamics and mixing efficiency for propeller impellers, Chem. Eng. Res. Des. 199 (2023) 460-472.
[18] X. Xiong, S.S. Wang, P.Q. Liu, C.Y. Tao, Y.D. Wang, Z.H. Liu, Numerical investigation on intensified mixing performance with modified dual impeller, Chem. Eng. Sci. 274 (2023) 118698.
[19] X.Y. Tang, F.C. Qiu, P.Q. Liu, H. Li, Z.H. Liu, Revealing chaotic advection dynamics in the chaotic mixing of non-Newtonian fluids within a stirred tank employing a twisted-punched impeller, Ind. Eng. Chem. Res. 63 (32) (2024) 14259-14274.
[20] J. Aubin, C. Xuereb, Design of multiple impeller stirred tanks for the mixing of highly viscous fluids using CFD, Chem. Eng. Sci. 61 (9) (2006) 2913-2920.
[21] M. Wu, N. Jurtz, L. Hohl, M. Kraume, Multi-objective geometrical optimization of single and dual impeller stirred tanks: an application of the mean age theory approach, Chem. Eng. Res. Des. 203 (2024) 709-720.
[22] J.C. Long, X.B. Zhan, F. Guo, Z.B. Sun, B.J. Shen, Y. He, X.W. Li, Study of hydrodynamics and flow characteristics in a twin-blade planetary mixer with non-Newtonian fluids, AIChE. J. 68 (10) (2022) e17797.
[23] G. Ascanio, M. Brito-Bazan, E.B. La Fuente, P.J. Carreau, P.A. Tanguy, Unconventional configuration studies to improve mixing times in stirred tanks, Can. J. Chem. Eng. 80 (4) (2002) 558-565.
[24] G. Ascanio, S. Foucault, M. Heniche, C. Rivera, P.A. Tanguy, Chaotic mixing in stirred vessels: a new strategy to enhance homogeneity, Ingenieria Mecanica. Tecnologia y Desarrollo. 1 (2005) 209-214.
[25] H. Ameur, 3D hydrodynamics involving multiple eccentric impellers in unbaffled cylindrical tank, Chin. J. Chem. Eng. 24 (5) (2016) 572-580.
[26] T. Meng, Y. Wang, S.S. Wang, S. Qin, Q. Zhang, Y.D. Wang, C.Y. Tao, Y.Q. Xu, Z.H. Liu, Exploration of multishafts stirred reactors: an investigation on experiments and large eddy simulations for turbulent chaos and mixing characteristics, Ind. Eng. Chem. Res. 63 (5) (2024) 2441-2456.
[27] T. Meng, J. Yang, S.S. Wang, Y. Wang, S. Qin, Y.D. Wang, C.Y. Tao, Q. Zhang, Z.H. Liu, Multi-shaft stirred reactors mixing efficiency: Rapid characterization strategy based on chaotic attractors, AlChE. J. 70 (10) (2024) e18510.
[28] H.S. Dou, Origin of Turbulence: Energy Gradient Theory. Springer Singapore, (2022).
[29] P.A. Tanguy, G. Ascanio, Mixing of shear-thinning fluids with dual off-centred impellers, Can. J. Chem. Eng. 83 (3) (2005) 393-400.
[30] H. Yao, J.J. Tang, Z.H. Liu, C.Y. Tao, Y.D. Wang, Chaotic mixing intensification and flow field evolution mechanism in a stirred reactor using a dual-shaft eccentric impeller, Ind. Eng. Chem. Res. 61 (26) (2022) 9498-9513.
[31] S.S. Wang, H. Li, C.Y. Tao, R.L. Liu, Y.D. Wang, Z.H. Liu, Study on cavern evolution and performance of three mixers in agitation of yield-pseudoplastic fluids, Chin. J. Chem. Eng. 55 (2023) 111-122.
[32] J. Aubin, D.F. Fletcher, C. Xuereb, Modeling turbulent flow in stirred tanks with CFD: the influence of the modeling approach, turbulence model and numerical scheme, Exp. Therm. Fluid Sci. 28 (5) (2004) 431-445.
[33] J.B. Joshi, N.K. Nere, C.V. Rane, B.N. Murthy, C.S. Mathpati, A.W. Patwardhan, V.V. Ranade, CFD simulation of stirred tanks: Comparison of turbulence models (Part II: Axial flow impellers, multiple impellers and multiphase dispersions), Can. J. Chem. Eng. 89 (4) (2011) 754-816.
[34] J.B. Joshi, N.K. Nere, C.V. Rane, B.N. Murthy, C.S. Mathpati, A.W. Patwardhan, V.V. Ranade, CFD simulation of stirred tanks: Comparison of turbulence models. Part I: Radial flow impellers, Can. J. Chem. Eng. 89 (1) (2011) 23-82.
[35] Z.T. Jia, S.F. Zhang, K.F. Fang, B. Kong, M.H. Xie, Q.H. Zhang, C. Yang, Assessment of stress-blended eddy simulation on prediction of flow characteristics in a Rushton impeller stirred tank, Chem. Eng. Sci. 284 (2024) 119442.
[36] O.P. Klenov, A.S. Noskov, Solid dispersion in the slurry reactor with multiple impellers, Chem. Eng. J. 176 (2011) 75-82.
[37] Y.N. Yang, Y.N. Zhou, B. Ouyang, Y.Y. Wu, X.B. Zhang, Z.H. Luo, Influence of thermal runaway in styrene-acrylonitrile bulk copolymerization revealed by computational fluid dynamics modeling, AlChE. J. 68 (5) (2022) e17645.
[38] Z.M. Kang, L.F. Feng, J.J. Wang, Optimization of a gas-liquid dual-impeller stirred tank based on deep learning with a small data set from CFD simulation, Ind. Eng. Chem. Res. 63 (1) (2024) 843-855.
[39] R. Zadghaffari, J.S. Moghaddas, J. Revstedt, Large-eddy simulation of turbulent flow in a stirred tank driven by a Rushton turbine, Comput. Fluids 39 (7) (2010) 1183-1190.
[40] N. Lamarque, B. Zoppe, O. Lebaigue, Y. Dolias, M. Bertrand, F. Ducros, Large-eddy simulation of the turbulent free-surface flow in an unbaffled stirred tank reactor, Chem. Eng. Sci. 65 (15) (2010) 4307-4322.
[41] B.Q. Liu, M.M. Wang, J.L. Liu, L.Y. Qian, Z.J. Jin, Experimental study on micromixing characteristics of novel large-double-blade impeller, Chem. Eng. Sci. 123 (2015) 641-647.
[42] A. Line, Energy consumption to achieve macromixing revisited, Chem. Eng. Res. Des. 108 (2016) 81-87.
[43] U. Schumann, Subgrid scale model for finite difference simulations of turbulent flows in plane channels and annuli, J. Comput. Phys. 18 (4) (1975) 376-404.
[44] ANSYS Inc, ANSYS FLUENT Theory Guide Inc. release 19.2. ANSYS Academic Research, (2019).
[45] J. Smagorinsky, General circulation experiments with the primitive equations, Mon. Wea. Rev. 91 (3) (1963) 99-164.
[46] A. Delafosse, J. Morchain, P. Guiraud, A. Line, Trailing vortices generated by a rushton turbine: assessment of URANS and large eddy simulations, Chem. Eng. Res. Des. 87 (4) (2009) 401-411.
[47] T. Henriques, M. Ribeiro, A. Teixeira, L. Castro, L. Antunes, C. Costa-Santos, Nonlinear methods most applied to heart-rate time series: a review, Entropy 22 (3) (2020) 309.
[48] N. Sarkar, B.B. Chaudhuri, An efficient differential box-counting approach to compute fractal dimension of image, IEEE Trans. Syst. Man Cybern. 24 (1) (1994) 115-120.
[49] P. Grassberger, I. Procaccia, Estimation of the Kolmogorov entropy from a chaotic signal, Phys. Rev. A 28 (4) (1983) 2591-2593.
[50] G. Benettin, L. Galgani, J.M. Strelcyn, Kolmogorov entropy and numerical experiments, Phys. Rev. A 14 (6) (1976) 2338-2345.
[51] R. Govindarajan, K.C. Sahu, Instabilities in viscosity-stratified flow, Annu. Rev. Fluid Mech. 46 (2014) 331-353.
[52] T. Meng, Y. Wang, S. Qin, P.Q. Liu, Y.D. Wang, C.Y. Tao, Z.H. Liu, Complex flow field analysis in Multi-Shaft stirred Reactors: Dynamics of Wave-Vortex coupling revealed by POD and DMD methods, Chem. Eng. Sci. 301 (2025) 120753.

Different rotation speeds: A novel approach to enhancing chaos and mixing efficiency in multi-shaft stirred reactors

Different rotation speeds: A novel approach to enhancing chaos and mixing efficiency in multi-shaft stirred reactors

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