Mechanism analysis and mixing characterization of variable-speed mechanical mixing enhancement
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Yuchen Lin
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Hua Wang
Abstract
In response to the observed phenomenon of poor fluid mixing within the reactor, this study proposes a novel mixing method to enhance fluid mixing efficiency. In this study, numerical simulation and purification tests were carried out for the purification of zinc sulfate solution. Numerical simulations were conducted to compare the effects of variable-speed stirring and uniform-speed stirring on mixing efficiency, considering both momentum transfer process and mass transfer process. The purification test further demonstrated a significant improvement in the reaction rate under variable-speed stirring, as evidenced by the analysis of purification efficiency and microscopic morphology. It was elaborated that the enhancement mechanism of variable-speed stirring involved disrupting the periodic order structure in the tank, leading to the generation of a multi-scale vortex that increased stirring kinetic energy to form a shear force. This force contributed to reducing the velocity slip between the impurity ions and zinc particles, consequently decreasing reaction time and enhancing purification rate. The results indicated that sinusoidal stirring yielded the most effective mixing. When implemented in practical production settings, it enhanced dimensionless mixing efficiency by 24.83 % compared to the homogeneous stirring system. Additionally, it reduced reaction time by 15.47 % and decreased mixing energy per unit volume by 32.38 %, while simultaneously lowering energy consumption by 24.77 %.
Funding source: National Natural Science Foundation of China
Award Identifier / Grant number: No. 52166004
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Research ethics: This study complies with the data is true without falsification, to improve the traditional mixing and blending process in the common problem, to propose quality solutions.
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Author contributions: The authors have accepted responsibility for the entire content of this manuscript and approved its submission.
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Competing interests: The authors state no conflict of interest.
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Research funding: None declared.
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Data availability: The raw data can be obtained on request from the corresponding author.
References
[1] J. Vassilicos, “Mixing in vortical, chaotic and turbulent flows,” Philos. Trans. Roy. Soc. London Ser. A Math. Phys. Eng. Sci., vol. 360, no. 1801, pp. 2819–2837, 2002, https://doi.org/10.1098/rsta.2002.1093.Search in Google Scholar PubMed
[2] X. Pan, L. Ding, P. Luo, H. Wu, Z. Zhou, and Z. Zhang, “LES and PIV investigation of turbulent characteristics in a vessel stirred by a novel long-short blades agitator,” Chem. Eng. Sci., vol. 176, pp. 343–355, 2018, https://doi.org/10.1016/j.ces.2017.10.054.Search in Google Scholar
[3] I. Birloaga and F. Vegliò, “An innovative hybrid hydrometallurgical approach for precious metals recovery from secondary resources,” J. Environ. Manage., vol. 307, p. 114567, 2022. https://doi.org/10.1016/j.jenvman.2022.114567.Search in Google Scholar PubMed
[4] K. Esyra Hani Ku Ishak, S. Ismail, and M. Irfan Bin Abd Razak, “Recovery of copper and valuable metals from E-waste via hydrometallurgical method,” Mater. Today: Proc., vol. 66, no. 5, pp. 3077–3081, 2022. https://doi.org/10.1016/j.matpr.2022.07.395.Search in Google Scholar
[5] C. Carletti, S. Bikić, G. Montante, and A. Paglianti, “Mass transfer in dilute solid–liquid stirred tanks,” Ind. Eng. Chem. Res., vol. 57, no. 18, pp. 6505–6515, 2018, https://doi.org/10.1021/acs.iecr.7b04730.Search in Google Scholar
[6] L. Labík, T. Moucha, R. Petříček, J. F. Rejl, L. Valenz, and J. Haidl, “Volumetric mass transfer coefficient in viscous liquid in mechanically agitated fermenters. Measurement and correlation,” Chem. Eng. Sci., vol. 170, pp. 451–463, 2017, https://doi.org/10.1016/j.ces.2017.04.006.Search in Google Scholar
[7] R. Petříček, T. Moucha, F. J. Rejl, L. Valenz, J. Haidl, and T. Čmelíková, “Volumetric mass transfer coefficient, power input and gas hold-up in viscous liquid in mechanically agitated fermenters. Measurements and scale-up,” Int. J. Heat Mass Transfer, vol. 124, pp. 1117–1135, 2018, https://doi.org/10.1016/j.ijheatmasstransfer.2018.04.045.Search in Google Scholar
[8] K. Inkong, P. Rangsunvigit, S. Kulprathipanja, and P. Linga, “Effects of temperature and pressure on the methane hydrate formation with the presence of tetrahydrofuran (THF) as a promoter in an unstirred tank reactor,” Fuel, vol. 255, p. 115705, 2019. https://doi.org/10.1016/j.fuel.2019.115705.Search in Google Scholar
[9] L. Tian, Z. Xu, L. Chen, Y. Liu, and T.-A. Zhang, “Study on oxygen gas holdup and kinetics using various types of paddles during marmatite leaching process,” Hydrometallurgy, vol. 180, pp. 158–171, 2018, https://doi.org/10.1016/j.hydromet.2018.06.011.Search in Google Scholar
[10] F. Tian, C. Yang, E. Zhang, D. Sun, W. Shi, and Y. Chen, “A study on the multi-objective optimization method and characteristic analysis of installation locations of submersible mixer for sewage,” Front. Energy Res., vol. 11, p. 1180607, 2023. https://doi.org/10.3389/fenrg.2023.1180607.Search in Google Scholar
[11] A. Ochieng and M. Onyango, “CFD simulation of solids suspension in stirred tanks: review,” Hem. Ind., vol. 64, no. 5, pp. 365–374, 2010, https://doi.org/10.2298/hemind100714051o.Search in Google Scholar
[12] S. L. Brunton, B. R. Noack, and P. Koumoutsakos, “Machine learning for fluid mechanics,” Annu. Rev. Fluid Mech., vol. 52, no. 1, pp. 477–508, 2020, https://doi.org/10.1146/annurev-fluid-010719-060214.Search in Google Scholar
[13] J. Li, M. Tian, and Y. Li, “Synchronizing large eddy simulations with direct numerical simulations via data assimilation,” Phys. Fluids, vol. 34, no. 6, p. 065108, 2022. https://doi.org/10.1063/5.0089895.Search in Google Scholar
[14] S. Benyahia, “Simulation of heavy particles fluidized with non-Newtonian fluids,” Powder Technol., vol. 433, p. 119261, 2024. https://doi.org/10.1016/j.powtec.2023.119261.Search in Google Scholar
[15] J. Mueller, D. Schmidt, and K. Velten, “Transient boundary condition approach for simulating mechanical mixing in large wine tanks,” Comput. Electron. Agric., vol. 150, pp. 143–151, 2018, https://doi.org/10.1016/j.compag.2018.04.012.Search in Google Scholar
[16] L. Zhang, K. Yang, M. Li, Q. Xiao, and H. Wang, “Enhancement of solid-liquid mixing state quality in a stirred tank by cascade chaotic rotating speed of main shaft,” Powder Technol., vol. 397, p. 117020, 2022. https://doi.org/10.1016/j.powtec.2021.11.064.Search in Google Scholar
[17] D. Gu, Z. Liu, J. Li, Z. Xie, C. Tao, and Y. Wang, “Intensification of chaotic mixing in a stirred tank with a punched rigid-flexible impeller and a chaotic motor,” Chem. Eng. Process. Process Intensif., vol. 122, pp. 1–9, 2017, https://doi.org/10.1016/j.cep.2017.08.017.Search in Google Scholar
[18] M. Fan, et al., “Enhancement of chaotic mixing performance in laminar flow with reciprocating and rotating coupled agitator,” Chem. Eng. Sci., vol. 280, p. 118988, 2023. https://doi.org/10.1016/j.ces.2023.118988.Search in Google Scholar
[19] Y. Fan, J. Sun, J. Jin, H. Zhang, and W. Chen, “The effect of baffle on flow structures and dynamics stirred by pitch blade turbine,” Chem. Eng. Res. Des., vol. 168, pp. 227–238, 2021, https://doi.org/10.1016/j.cherd.2021.01.017.Search in Google Scholar
[20] Q. Zhang, S. Wang, H. Wang, J. Xu, C. Li, and Q. Xiao, “Numerical and experimental investigations on enhancement mixing performance of multi-blade stirring system for fluids with different viscosities,” Int. J. Chem. React. Eng., vol. 21, no. 8, pp. 951–964, 2023, https://doi.org/10.1515/ijcre-2022-0151.Search in Google Scholar
[21] D. Gu, C. Cheng, Z. Liu, and Y. Wang, “Numerical simulation of solid-liquid mixing characteristics in a stirred tank with fractal impellers,” Adv. Powder Technol., vol. 30, no. 10, pp. 2126–2138, 2019, https://doi.org/10.1016/j.apt.2019.06.028.Search in Google Scholar
[22] H. Ameur and M. Bouzit, “3D hydrodynamics and shear rates’ variability in the United States pharmacopeia paddle dissolution apparatus,” Int. J. Pharm., vol. 452, nos. 1–2, pp. 42–51, 2013, https://doi.org/10.1016/j.ijpharm.2013.04.049.Search in Google Scholar PubMed
[23] H. Ameur, “Mixing of a viscoplastic fluid in cylindrical vessels equipped with paddle impellers,” ChemistrySelect, vol. 2, no. 35, pp. 11492–11496, 2017, https://doi.org/10.1002/slct.201702459.Search in Google Scholar
[24] D. Sahel, Y. Kamla, and H. Ameur, “Optimization of the operating and design conditions to reduce the power consumption in a vessel stirred by a paddle impeller,” Period. Polytech. Mech. Eng., vol. 62, no. 4, pp. 312–319, 2018, https://doi.org/10.3311/PPme.12372.Search in Google Scholar
[25] H. Ameur, “Mixing of complex fluids with flat and pitched bladed impellers: effect of blade attack angle and shear-thinning behaviour,” Food Bioprod. Process., vol. 99, pp. 71–77, 2016, https://doi.org/10.1016/j.fbp.2016.04.004.Search in Google Scholar
[26] H. Ameur, “Modifications in the Rushton turbine for mixing viscoplastic fluids,” J. Food Eng., vol. 233, pp. 117–125, 2018, https://doi.org/10.1016/j.jfoodeng.2018.04.005.Search in Google Scholar
[27] J.-H. Ji, R.-Q. Liang, and J.-C. He, “Simulation on mixing behavior of desulfurizer and high-sulfur hot metal based on variable-velocity stirring,” ISIJ Int., vol. 56, no. 5, pp. 794–802, 2016, https://doi.org/10.2355/isijinternational.ISIJINT-2015-549.Search in Google Scholar
[28] Y. Fan, et al., “Enhancement of mixing efficiency in mechanical stirring reactors via chaotic stirring techniques: application to the treatment of zinc-containing solid waste,” Chem. Eng. Sci., vol. 249, p. 117367, 2022. https://doi.org/10.1016/j.ces.2021.117367.Search in Google Scholar
[29] Y. Fan, S. Wang, H. Wang, J. Xu, Q. Xiao, and Y. Wei, “Formation mechanism and chaotic reinforcement elimination of the mechanical stirring isolated mixed region,” Int. J. Chem. React. Eng., vol. 19, no. 3, pp. 239–250, 2021, https://doi.org/10.1515/ijcre-2020-0213.Search in Google Scholar
[30] X. Liu, S. Wang, Z. Peng, G. Zhang, Q. Gui, and L. Zhang, “Removal of toxic cadmium (II) from zinc sulfate solution with zinc powder enhanced by ultrasound: kinetics and mechanism,” Sep. Purif. Technol., vol. 308, p. 122995, 2023, https://doi.org/10.1016/j.seppur.2022.122995.Search in Google Scholar
[31] M. Wang, et al.., “Functional waveform pulse variable speed stirring to improve mechanistic analysis and experimental study on the purification efficiency of zinc sulfate solution,” Int. J. Chem. React. Eng., vol. 21, no. 1, pp. 23–39, 2023, https://doi.org/10.1515/ijcre-2022-0049.Search in Google Scholar
[32] M. Zhao, L. Cheng, H. An, and L. Lu, “Three-dimensional numerical simulation of vortex-induced vibration of an elastically mounted rigid circular cylinder in steady current,” J. Fluids Struct., vol. 50, pp. 292–311, 2014, https://doi.org/10.1016/j.jfluidstructs.2014.05.016.Search in Google Scholar
[33] W. Li, et al.., “Enhanced mechanical stirring by eccentric impeller stirring system in zinc hydrometallurgy process for cadmium removal,” Int. J. Chem. React. Eng., vol. 21, no. 8, pp. 921–936, 2023, https://doi.org/10.1515/ijcre-2022-0148.Search in Google Scholar
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Articles in the same Issue
- Frontmatter
- Articles
- Study on mixing characteristics of viscoplastic fluid in a rigid-flexible impeller stirred tank
- Emission and performance investigation of mango seed oil biodiesel supplied with n-pentanol and n-hexanol additives and optimization of fuel blends using modified deep neural network
- Study of chlorophyll dye from peppermint (mentha spicata) used as a sensitizer in TiO2 solar cells
- Dry reforming of methane over Ni–Mg–Al and Ni–Ca–Al type hydrotalcite-like catalysts: effects of synthesis route and Ru incorporation
- CFD-DEM simulation of chemical looping hydrogen generation in a moving bed reactor
- Conceptual design of a fixed bed N2O decomposition reactor with a heat pipe heat exchanger
- Investigation of polymers pyrolysis in a solid-gas conical spouted bed: CFD simulation
- CFD simulation study of internal mixing and flow of a modified airlift bioreactor
- Mechanism analysis and mixing characterization of variable-speed mechanical mixing enhancement
- Enhanced sonocatalytic degradation of Acid Red 27 with Fe2O3 catalyst: a kinetic study
