Simone CASTELLANO will support her thesis on November 5, 2019, at 10 am, at the amphitheater of the library
Title of the thesis : Multiscale study and modeling of dispersion properties for liquid-liquid extraction. Adaptation of breakup and coalescence kernels to industrial processes
Professeur Baldyga Jerzy /Université de technologie de Varsovie – Rapporteur
Professeur Nopens Ingmar/Université de Gand – Rapporteur
Professeur Lance Michel/Université Claude Bernard Lyon 1 -Examinateur
Professeur Schaer Eric/Université de Lorraine – Examinateur
Docteur Othman Nida/Université Claude Bernard Lyon 1 – Directrice de thèse
Docteur Charton Sophie/Commissariat à l’Energie Atomique -Co-directrice de thèse
Dr. Antonio Buffo / Polito de Turrin – invité
Dr. Samer Alzyod / CEA – invité
This PhD project deals with the study of the hydrodynamics of the dispersions in the liquid-liquid extractors employed in the nuclear recycle industry.
In the first part of the project, a zero-dimensional homogenous Population Balance Model (0D-PBM), based on the evaluation of the volume-averaged coalescence and breakup rates, is adopted to fit low-viscosity turbulent liquid-liquid dispersion experiments. The method accounts for the spatial inhomogeneities in mixing, namely for the probability density function of the turbulent kinetic energy dissipation in the apparatus.
In the second part of this study, a generalized model for the breakage and coalescence kernels, valid for the entire spectrum of turbulence, is proposed and validated. Most of the available kernels in literature indeed are based on the Kolmogorov second-order structure function, which is only valid in the inertial subrange. However, in many industrially encountered situations, most of the droplets may have size in the dissipation range, where the Kolmogorov second-order structure function does not apply. The generalized model is based on the Davidson second-order structure function, valid in the entire spectrum of turbulence.
In the last part of the study, a model that allows to simulate the hydrodynamic behavior of a pulsed column is proposed. The model is based on a 1D Population Balance Equation (1D-PBE), whose source terms were modeled through the generalized Coulaloglou and Tavlarides kernels. The turbulent inhomogeneities in the pulsed column were accounted through the probability density function of the turbulent dissipation rate. The model well reproduces the experimental Sauter mean diameters and the dispersed phase volume fractions in a compartment of the pulsed column.
Date(s) - 5 Nov 2019
10 h 00 min - 12 h 00 min
Bibliothèque de la Doua
CatégoriesFiled under: Defense