Postdoctoral research project
Numerical study of the transport phenomena in bubbly flow close to the anode
surface in a reactor for aluminum production
Context and system description:
The post-doc project is part of a process development technology dedicated to aluminum production by
electrolysis in a molten-salts medium. The process avoids releasing greenhouse gases thanks to the
replacement of standard carbon anodes by stable inert anodes (ANR MIMINELA). The system of interest
is an experimental reactor at the lab scale, equipped with an X-Ray device, allowing to detect in situ the
size, number and speed of bubbles created at the anode. The plume of bubbles generated has an impact
on the mass and momentum transfer inside the reactor and mainly close to the anode. The aim of
this project is to quantify the effect of these phenomena on the performance of the reactor and the
lifetime of the anode, in order to propose possible system improvement.
Plan of work:
The study will be performed using modelling and numerical simulations following two complementary
tasks. The first task consists in studying the transport of species towards a rotating electrode in a singlephase bath (without bubbles). From the comparison of the numerical results with existing electrochemical
measurements (available at the Laboratory of Chemical Engineering LGC), this set of simulations will
allow identifying the suitable electrokinetic parameters of the reactions taking place at the anode surface.
The software Fluent will be used for this first part of the work.
The experiments realized on aluminum production reactors show that bubbles form at the anode, and their
size upon detachment (millimetric or micrometric bubbles) depends
drastically on the nature of the anode (gold or carbon) and on the
Anode
roughness of its surface. In the second task, the effect of bubble
Bath: species
motion on the species transport towards the anode surface will be
transport
considered, depending on the bubble size. Two-phase flow
influenced by
simulations will allow quantifying the coupling between mass and
the bubble
momentum transfer taking into account the relevant length scales.
presence and
The in-house code Jadim will be used for this part of the work
motion
(https://www.imft.fr/JADIM ).
We need a candidate who has a good experience in two-phase flow modeling, fluid mechanics / transport
phenomena, and numerical simulations. Knowledge in electrochemistry is not necessarily required.
Research lab: Laboratoire de Génie Chimique, Toulouse, France
Starting date: November 2015 (flexible)
Duration: 18 months
Contact: Hugues.Vergnes@ensiacet.fr, Micheline.Abbas@ensiacet.fr