PhD Oscillating grid bioreactors for shear-sensitive micro-algae culture intensification

Discipline: Fluid mechanics and process engineering

Workplace: Douai, France and Mons, Belgium

Type of contract and duration: Doctoral contract, 36 months

CONTEXT: Public establishment belonging to IMT (Institut Mines-Télécom), placed under the supervision of the Ministry of Economy, Finance and Industrial and Digital Sovereignty, IMT Nord Europe has three main objectives: providing our students with ethically responsible engineering practice enabling them to solve 21st century issues, carrying out our R&D activities leading to outstanding innovations and supporting territorial development through innovation and entrepreneurship. Ideally positioned at the heart of Europe, 1 hour away from Paris, 30 min from Brussels and 1h30 from London, IMT Nord Europe has strong ambitions to become a main actor of the current industrial transitions, digital and environmental, by combining education and research on engineering and digital technologies. Located on two main campuses dedicated to research and education in Douai and Lille, IMT Nord Europe offers research facilities of almost 20,000m² in the following areas: Digital science, Energy and Environment, Materials and Processes. For more details, visit the School’s website: www.imt-nord-europe.fr

The position is vacant within the Centre for Energy and Environment (CERI EE). The successful applicant will join the Energy Fluids and Transfer research axis, and the Complex Fluid Flow lab, that conducts research on complex fluids and complex flows involved in transfer intensification. In collaboration with the University of Mons in Belgium, the group has recently developed research activities around the flow-based intensification of bioprocesses and in particular micro-algae culture.

The latter represents a major lever for the ecological transition, enabling the conversion of CO₂ into exploitable biomass for the production of high value-added molecules or energy carriers. However, the development of high-performance photobioreactors (PBRs) faces scientific and technological challenges, notably due to limitations related to mixing, light distribution homogeneity, and shear stress constraints in conventional systems. Oscillating grid devices (OGDs) offer a promising alternative, as they are able to generate homogeneous turbulence that enhances mass transfer while preserving the integrity of sensitive microalgae. Previous works by the team have demonstrated the potential of oscillating fractal grids to intensify turbulence and improve mixing and cultivation efficiency.

The present PhD project, OPTIFROG, builds on these advances and aims to optimize this concept of photobioreactors with oscillating fractal grids. The research will focus on detailed characterization and modelling of hydrodynamic mechanisms (both experimentally and numerically), the investigation of new multi-grid agitation strategies and lighting, and the validation of biological performance on cultures. This project thus seeks to propose an innovative, energy-efficient, and scalable photobioreactor for the sustainable intensification of bioprocesses.