Missions

The development of biorefineries of microalgae represents a major industrial challenge, with the potential to provide answers to our society's energy and environmental problems. Once the cells have been lysed, one of the key steps is to separate the biomolecules (proteins, lipids and polysaccharides) from the crushed material, in order to concentrate and purify them. One of the processes selected is membrane filtration. The key issues at this stage are understanding the organization of target compounds in microalgae extracts, and then modifying this organization to facilitate fractionation and valorization of the various products.
The coupling of membrane filtration and enzyme catalysis has been identified as a potential candidate for increasing extraction yields. Indeed, identified enzymes can degrade compounds blocking biomolecules of interest. In order to develop this intensified process, the ANR-DFG “PREMIUM” project has recently started involving GEPEA (St-Nazaire, FR), IOM (Leipzig, D) and IMN (Nantes, FR) laboratories. The aim is to develop the process from the manufacturing of the membrane and the ion beam grafting of the enzymes by IOM, to the development and optimization of the actual process by GEPEA, while investigating the fooling fouling of used membrane through cryo electron microscopy by IMN.
This research engineer position is part of the PREMIUM project led by the GEPEA partner, and aims to model the hybrid enzymatic membrane process, where strong couplings between reaction and transfer phenomena are expected. The research engineer will also be involved in a collaboration between GEPEA and LGC (Toulouse, FR). This supplementary collaboration aims to tackle specific modeling issues, since (1) an intricate interaction between transport phenomena and reaction is expected in the context of a multiphase reactor, (2) a dedicated methodology needs to be applied in order to bridge the gap between numerical simulations and the actual process involving complex medium.

Activités

After a thorough bibliographic study on the modelling of biocatalytic membrane reactor (BMR) in the context of biomolecules extraction from complex media, the candidate is expected to elaborate a modelling strategy. First, degenerate models will be developed using a multiphysics approach4,5 based on relevant dimensionless numbers to identify limiting transfer phenomena and main sizing parameters. Complex case study will then consider realistic physical and chemical properties of the microalgae extracts, and enzymatic reactions. Comparison between model predictions and experimental results from the actual reaction-separation process, as well as sensitivity analyses, will provide insight into the specific effects of the complex media characteristics and the enzyme catalysis. The validated model will then be used to optimize operating conditions to maximize biomolecule extraction.
In addition to his/her contribution to the model development, the research engineer will take active part in the discussions with all the partners of the PREMIUM project: GEPEA team on the pilot development, operating conditions and operation with microalgae extracts, IOM partner on the development and structure of the grafted polymer membrane and, IMN on the identification of the membrane fouling mechanisms and evaluation of the enzyme distribution in the porous media and how it enhances targeted reactions and biomolecule mass transfer.
Other tasks and duties:
• Conceptualization, data curation, formal analysis, drafting of original articles for international peer-reviewed journals.
• Contribution to the project management tasks: writing of project reports and deliverables.
• Presentations at scientific meetings and workshops.

Compétences

• PhD thesis in Chemical Engineering, Bioprocesses or Food Engineering
• Background (knowledge prerequisites): Heterogenous catalysis, Separation processes, Transport phenomena
• Strong computer skills: CFD softwares (ANSYS, COMSOL, …), Matlab, Python, …
• Required qualities: Good problem-solving skills; attention to detail; adaptability, ability to work independently, strong organizational skills.
• Open-mindedness and ability to work in a team, given the multidisciplinary and collaborative nature of the project.
• Ability to communicate in English, both orally and in writing.

Contexte de travail

The Process Engineering, Environment and Food Laboratory (GEPEA, https://www.gepea.fr/) is one of the leading French laboratories in the field of Process Engineering. The proposed subject is part of the project PREMIUM, led by E. Couallier and supported by the French and German national research agencies (ANR and DFG). The project involves three laboratories with strong collaborations: GEPEA, the Institute for Surface Engineering in Leipzig, Germany (IOM, https://www.iom-leipzig.de/en/) and the Materials Institute in Nantes (IMN, https://www.cnrs-imn.fr/). The position is also part of a collaboration between specialists of process modeling in GEPEA (P. Albrand) and LGC (C. Julcour). Most of the research will be carried out at GEPEA in Saint-Nazaire. The research engineer will be part of GEPEA's Bioprocesses Applied to Microalgae team, and will be involved in the field of biorefining. Several visits to the partners (IMN Nantes, IOM in Germany) are also planned.

Contraintes et risques

No specific risk or constraints expected

Informations complémentaires

Key words:
Modelling, CFD, process, membrane, microalgae, biorefining