Numerical simulation of two-phase flow and droplet breakage of glycerin-water mixture and kerosene in the cyclone reactor

doi:10.1016/j.cjche.2021.02.021

Abstract

Abstract: A liquid-liquid cyclone reactor (LLCR) was designed to achieve mixing-reaction-separation integration during isobutane alkylation catalyzed by ionic liquids. However, studies of the droplets deformation and breakage in the kind of reactors are lacking. In this work, the research studied the velocity distribution, pressure field, and turbulent field to investigate the flow pattern and the main energy loss location in the LLCR through the computational fluid dynamics (CFD) method. The simulation results were verified by experiemnts to prove the correctness of the model. Then the deformation and breakage process of droplets, and the influencing factors of droplets breakage were studied by remodeling which was based on the tangential velocity distribution result of the three dimensional model. The three dimensional simulation results clearly showed that the pressure of the LLCR was mainly concentrated in the cone section and fluid turbulent motion was the most intense near the lateral wall. The reconstruct the results of the two dimensional model clearly showed that the deformation and breakage location of droplets were mainly occurred in the velocity boundary layer, while it was difficult to break in the mainstream region. In addition, low surface tension and high Weber number had a positive effect on droplet breakage.

Key words: Liquid-liquid cyclone reactor, Ionic liquid, separation, Droplet deformation, Droplet breakage, Computational fluid dynamics

摘要： A liquid-liquid cyclone reactor (LLCR) was designed to achieve mixing-reaction-separation integration during isobutane alkylation catalyzed by ionic liquids. However, studies of the droplets deformation and breakage in the kind of reactors are lacking. In this work, the research studied the velocity distribution, pressure field, and turbulent field to investigate the flow pattern and the main energy loss location in the LLCR through the computational fluid dynamics (CFD) method. The simulation results were verified by experiemnts to prove the correctness of the model. Then the deformation and breakage process of droplets, and the influencing factors of droplets breakage were studied by remodeling which was based on the tangential velocity distribution result of the three dimensional model. The three dimensional simulation results clearly showed that the pressure of the LLCR was mainly concentrated in the cone section and fluid turbulent motion was the most intense near the lateral wall. The reconstruct the results of the two dimensional model clearly showed that the deformation and breakage location of droplets were mainly occurred in the velocity boundary layer, while it was difficult to break in the mainstream region. In addition, low surface tension and high Weber number had a positive effect on droplet breakage.

关键词: Liquid-liquid cyclone reactor, Ionic liquid, separation, Droplet deformation, Droplet breakage, Computational fluid dynamics

Yanni Chi, Rui Zhang, Xianghai Meng, Jian Xu, Wei Du, Haiyan Liu, Zhichang Liu. Numerical simulation of two-phase flow and droplet breakage of glycerin-water mixture and kerosene in the cyclone reactor[J]. Chinese Journal of Chemical Engineering, 2021, 34(6): 150-159.

References

[1] L.F. Albright, R.E. Eckert, Formation and separation of sulfuric acid/n-heptane dispersions:Applications to alkylation, Ind. Eng. Chem. Res. 40(19) (2001) 4032-4039.
[2] S.J. Aschauer, A. Jess, Effective and intrinsic kinetics of the two-phase alkylation of i-paraffins with olefins using chloroaluminate ionic liquids as catalyst, Ind. Eng. Chem. Res. 51(50) (2012) 16288-16298.
[3] L. Schilder, S. Maaß, A. Jess, Effective and intrinsic kinetics of liquid-phase isobutane/2-butene alkylation catalyzed by chloroaluminate ionic liquids, Ind. Eng. Chem. Res. 52(5) (2013) 1877-1885.
[4] L. Schmerling, The mechanism of the alkylation of paraffins. II. alkylation of isobutane with propene, 1-butene and 2-butene, J. Am. Chem. Soc. 68(2) (1946) 275-281.
[5] Z.C. Liu, R. Zhang, C.M. Xu, R.G. Xia, Ionic liquid alkylation process produces high-quality gasoline, Oil Gas J. 104(40) (2006) 52-56.
[6] J.J. Zhou, Z.C. Liu, M.X. Liu, C.X. Lu, C.M. Xu, Structure optimization of the new alkylation reactor and experimental study on the drop diameter distribution in it, Acta Petrolei Sin. Petroleum Process. Sect. 24(2) (2008) 134-140.
[7] Z.B. Wang, Z.C. Liu, C.M. Xu, A.Q. Chen, R. Zhang, Liquid-liquid Heterogeneous Mixingreaction separation Integrated Short-contact Cyclone Reactor. China. Pat., 104971673B (2015).
[8] S.Q. Duan, M. Chen, R. Zhang, X.H. Meng, J. Xu, W. Du, Z.B. Wang, Z.C. Liu, Effect of light phase inlet structure on liquid-liquid cyclone reactor for isobutane alkylation catalyzed by ionic liquid, Chem. Eng. Process.-Process. Intensif. 140(2019) 22-28.
[9] M. Narasimha, R. Sripriya, P.K. Banerjee, CFD modelling of hydrocyclone-prediction of cut size, Int. J. Miner. Process. 75(1-2) (2005) 53-68.
[10] M.Y. Zhang, X.Y. Li, S.J. Li, Y. Gao, Z.B. Wang, L.H. Zhang, H. Zhang, B. Li, Cold model investigation of mixing-separation time distribution in a multi-element process coupled cyclone reactor for ionic liquid-catalyzed isobutane/butene alkylation, RSC Adv. 9(49) (2019) 28399-28408.
[11] S.Q. Duan, X.H. Meng, R. Zhang, H.Y. Liu, J. Xu, W. Du, C.M. Xu, Z.C. Liu, Experimental and computational investigation of mixing and separation performance in a liquid-liquid cyclone reactor, Ind. Eng. Chem. Res. 58(51) (2019) 23317-23329.
[12] S. Huang, Numerical simulation of oil-water hydrocyclone using Reynoldsstress model for Eulerian multiphase flows, Can. J. Chem. Eng. 83(5) (2005) 829-834.
[13] Y.H. Zhang, P. Qian, Y. Liu, H.L. Wang, Experimental study of hydrocyclone flow field with different feed concentration, Ind. Eng. Chem. Res. 50(13) (2011) 8176-8184.
[14] N.Y. Zhou, Y.X. Gao, W. An, M. Yang, Investigation of velocity field and oil distribution in an oil-water hydrocyclone using a particle dynamics analyzer, Chem. Eng. J. 157(1) (2010) 73-79.
[15] M. Nishikawa, F. Mori, T. Kayama, S. Nishioka, Drop size distribution in a liquid-liquid phase mixing vessel, J. Chem. Eng. Japan 24(1) (1991) 88-94.
[16] W. Du, N. Quan, P.P. Lu, J. Xu, W.S. Wei, L.F. Zhang, Experimental and statistical analysis of the void size distribution and pressure drop validations in packed beds, Chem. Eng. Res. Des. 106(2016) 115-125.
[17] J. Solsvik, H.A. Jakobsen, Single drop breakup experiments in stirred liquidliquid tank, Chem. Eng. Sci. 131(2015) 219-234.
[18] A.N. Sathyagal, D. Ramkrishna, G. Narsimhan, Droplet breakage in stirred dispersions. Breakage functions from experimental drop-size distributions, Chem. Eng. Sci. 51(9) (1996) 1377-1391.
[19] N. Hashemi, F. Ein-Mozaffari, S.R. Upreti, D.K. Hwang, Experimental investigation of the bubble behavior in an aerated coaxial mixing vessel through electrical resistance tomography (ERT), Chem. Eng. J. 289(2016) 402-412.
[20] S. Schütz, G. Gorbach, M. Piesche, Modeling fluid behavior and droplet interactions during liquid-liquid separation in hydrocyclones, Chem. Eng. Sci. 64(18) (2009) 3935-3952.
[21] M. Meyer, M. Bohnet, Influence of entrance droplet size distribution and feed concentration on separation of immiscible liquids using hydrocyclones, Chem. Eng. Technol. 26(6) (2003) 660-665.
[22] G.M. Xu, Z.H. Shu, W.M. Chen, The breakage of droplets in liquid-liquid hydrocyclones, Filter Sep. 13(1) (2003) 10-13.
[23] L.X. Zhao, M.H. Jiang, F. Li, J. He, J.L. Li, Analysis of force on dispersed phase droplet of cyclone-Research on the velocity field of the liquid-liquid hydrocyclone, Pet. Machinery. 5(27) (1999) 24-27.
[24] H.B. Xue, Y.H. Kang, W. Yao, L. Xiao, Research on distributing pattern of oil droplets on the inner wall of oil separating cyclone, China Pet. Machinery. 12(29) (2001) 1-3.
[25] M.Y. Zhang, A.J. Li, L.Y. Zhu, Z.B. Wang, Z.C. Liu, Y.H. Jin, Cold-model investigation of droplet size distribution of dispersed phase in a novel liquid-liquid cyclone reactor for ionic liquid catalyzed isobutane alkylation, Sep. Purif. Technol. 209(2018) 375-382.
[26] F. Parvaz, S.H. Hosseini, G. Ahmadi, K. Elsayed, Impacts of the vortex finder eccentricity on the flow pattern and performance of a gas cyclone, Sep. Purif. Technol. 187(2017) 1-13.
[27] N. Kharoua, L. Khezzar, Z. Nemouchi, Hydrocyclones for de-oiling applications-A review, Petroleum Sci. Technol. 28(7) (2010) 738-755.
[28] M. Saidi, R. Maddahian, B. Farhanieh, H. Afshin, Modeling of flow field and separation efficiency of a deoiling hydrocyclone using large eddy simulation, Int. J. Miner. Process. 112-113(2012) 84-93.
[29] A.M. Jawarneh, G.H. Vatistas, Reynolds stress model in the prediction of confined turbulent swirling flows, J. Fluids Eng. Trans. ASME 128(6) (2006) 1377-1382.
[30] M. Ghadirian, R.E. Hayes, J. Mmbaga, A. Afacan, Z.H. Xu, On the simulation of hydrocyclones using CFD, Can. J. Chem. Eng. 91(5) (2013) 950-958.
[31] M. Saidi, R. Maddahian, B. Farhanieh, Numerical investigation of cone angle effect on the flow field and separation efficiency of deoiling hydrocyclones, Heat Mass Transf. 49(2) (2013) 247-260.
[32] M. Narasimha, M. Brennan, P.N. Holtham, Large eddy simulation of hydrocyclone-prediction of air-core diameter and shape, Int. J. Miner. Process. 80(1) (2006) 1-14.
[33] D.A. Drew, Analytical Modeling of Multiphase Flows. Boiling Heat Transfer, Elsevier, Amsterdam, (1992) 31-84.
[34] J. Peng, X.J. Wang, L. Zou, G.H. Li, X. Zhang, J.N. Chen, Numerical simulation of three-dimensional two-phase flow field in a cyclone separator, Comput. Appl. Chem. 8(23) (2006) 728-732.
[35] L. Rao, P.J. Zhang, Z.Q. Cai, Z.M. Cai, Experimental study on the deformation and breakage of the single droplet in the jet field, Tech. Nat. (Sci. ed.) 43(3) (2016) 20-27.
[36] S. Galinat, O. Masbernat, P. Guiraud, C. Dalmazzone, C. Noïk, Drop break-up in turbulent pipe flow downstream of a restriction, Chem. Eng. Sci. 60(23) (2005) 6511-6528.