Axis 4 : Transfer, Interface, Mixing

Philippe SCHMITZ, Axis 4 Manager

philippe.schmitz @ +335 61 55 94 35


From the microscope to the bioreactor, from the micro-organism to the bubble


Resulting from two former teams that were working respectively on mass transfer in biological aggregates and chemical process engineering, TIM has organised its research strategy around a common science methodology ranging from the local phenomenon observations to the macroscopic scale through experimental and modelling investigations.


Three approaches are centred in the TIM axis :

  • The study of basic mechanisms in model systems.
  • Scaling up: from the microscopic level to the macroscopic reactor.
  • The pilot scale validation, which is the last step just before the industrial reactor or the water treatment plant.

By focusing on the mass transfer phenomenon occurring in multiphase media with and without reaction, or by investigating the flow field effect around a bubble or a micro-organism with a similar mass transfer mechanism, the TIM axis is characterised by a multidisciplinary research approach.




Themes and Technologies: experiments and modelling


Hydrodynamics, two phases flow, mass transfer, physical chemistry and microbiology are the major science topics used in the TIM axis. Two research approaches are systematically investigated: the experimental pathway and the numerical approach.

[O2] simulated in bubble wake

[O2] measured by PLIF in bubble wake


The TIM axis relies on its research facilities, dedicated or shared, including those within the research federation FERMAT, such as optical microscopy confocal, laser-induced fluorescence (PLIF), speed measurement by particle image velocimetry (PIV), high frequency camera and simulation software (DNS, LES, Eulerian and Lagrangian CFD), which allow movement from morphological analysis at the microscopic level to flow calculations on a large scale.

In parallel, a workshop provides mechanical design and construction of experimental devices that operate on specific model systems.


Sheared flow chamber with coupon for observation under an optical microscope. L. Lopez and C. Ellero (TIM work shop) - Flow validation by numerical simulation.

Sustainable development and the environment

Socio-economic issues that the TIM axis researches try to solve are those of sustainable development, with a strategic priority around water treatment and clean technology.

Tap water treatment, municipal or industrial waste water treatment, water reuse for irrigation in the Magreb countries and fermentative conversion of organic macromolecules of the cellulose type in synton and syngas are among the major application areas of research in the TIM axis.

Additionally, the nano-products fate in discharged liquids, VOCs (Volatile Organic Compounds) removal in the atmosphere, prevention of food contamination during the manufacturing process, the biofilm issues and their associated health risks, biofuel production and oil transportation improvement are some examples of industrial applications also developed in the TIM axis.


Captured particle visualisation

Bacillus Cereus spores on stainless steel (ANR Interspore)


The TIM axis research goal is to maintain its high level expertise on water treatment topics and to develop its knowledge of physical and biological sciences in order to address pervasive issues of industrial applications, as for example the white biotechnologies.


Application fields

Products examples


Treatment or valorisation for gas and liquid effluents from industries or municipal facilities

Water treatment

Scaling for aeration tanks and disinfection tanks, bio-filter setup


Biofuel production from algae



Food industry

Food contamination prevention during process production, fermentation


Prevention of biofilm growth

Oil industry

Oil transport in pipes

Oil-water separators and their improvement (wash tank, hydrocyclone hybrid)

The TIM axis, a major actor of the research federation FERMAT

One feature of the TIM axis of the LISBP is its involvement in the regional structure FERMAT (Fluid, Energy, Reactors, Materials and Transfers). Labeled "Search Federation" and funded by the State, its central objective is to initiate and support interdisciplinary research projects involving the Engineering Sciences developped in Toulouse and the Midi-Pyrénées region.

Bringing together six Toulouse laboratories with the National Polytechnic Institute of Toulouse, the National Institute of Applied Sciences of Toulouse, the Toulouse 3 University and the CNRS, this federation implements the pooling of fundamental concepts and advanced tools. To date, nine research themes are identified in three major areas:

  • The coupling between fluid mechanics and transfer of chemical or biological reagents
  • The reagent transfer or thermal transfer at the interface or at the thin layer vicinity
  • The coupling between the energy transfer properties and the material structures

The FERMAT federation contributes to a large part of the TIM strategy, e.g. it provides very powerful tools that are essential to the approach of multiscale modeling for multiphase contactors, which are the core business of the TIM axis. It is also a strong stimulus for exchanges and cross-sectoral multidisciplinary synergies in the Toulouse region.