Evaluation of breakage and coalescence kernel constants for a mixer tank in the copper solvent extraction unit

Document Type : Research Article


1 Department of Materials Engineering, Shahid Rajaee Teacher Training University (SRTTU), Tehran, Iran

2 Department of Materials and Metallurgical Engineering, Amirkabir University of Technology (AUT), Tehran, Iran

3 School of Chemical Engineering, Iran University of Science and Technology (IUST), Tehran, Iran


Since the Population Balance Model (PBM)  poses a significant problem (due to the effect of droplets size distribution on the mass transfer phenomenon) in mixers, researchers face difficulties during a Population Balance Equation (PBE) numerical investigation. Therefore, investigating PBM in mixers became more considerate in recent researches. In this study, the droplet size distribution of the organic phase, which is discrete in the aqueous phase, was obtained using experimental methods and experimental data analysis. A variance function, which produces different values between PBEs and experimental data, was used to obtain the constants of breakage and coalescence kernels. Results showed that the impeller speed and clearance had no effect on the PBEs constants. In addition to these operation parameters, impeller diameter and baffle width had very little effect on these constants. In contrast, the impeller type and the number of baffles had a large specific effect on the contents by deformation of the vortex configurations.

Graphical Abstract

Evaluation of breakage and coalescence kernel constants for a mixer tank in the copper solvent extraction unit


  • New breakage and coalescence equation constants have been developed.
  • Very well agreement with available experimental data has been found.
  • Parametric study of the kernels in different conditions and designs has been done.
  • A simplified PBM has been derived for CFD simulation.


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