Postdoctoral Researcher at Coldep (fr), part of Nijhuis Saur Industries

Scientific and Institutional Context Coldep’s core technology, the VAL process – Vacuum AirLift – is based on an original vertical vacuum flotation principle combining hydraulic circulation, dissolved gas regulation, and particle extraction. Following significant industrial deployment in the aquaculture sector (over 100 operational installations), VAL is now entering a structured research and upscaling phase targeting new strategic applications: seawater pre-treatment for desalination, complex industrial effluents, micropollutant removal, and water reuse. Since late 2025 , Coldep has been a subsidiary of Nijhuis Saur Industries ( Saur Group ), a global reference in innovative water treatment solutions. This integration marks a new development phase characterized by accelerated industrialization, strengthened R&D resources, and increased capacity to translate scientific challenges into robust industrial solutions. The research associated with this position benefits from public support from ADEME and from secured internal R&D funding, ensuring scientific continuity, credibility of allocated resources, and strong research ambition. Research Topics The postdoctoral researcher will contribute to several strategic R&D topics, listed below for guidance. These topics address key scientific and technological challenges supporting the short- and medium-term development of VAL technology within a context of industrial scaling, equipment standardization, and expansion into new markets. The exact scope, prioritization, and scientific depth of each topic may be adjusted depending on: the candidate’s profile and expertise, scientific interests, progress of industrial and partnership projects. The objective is not the execution of a fixed program, but active contribution to applied, evolutive, and industrialization-oriented R&D. Topic 1 – Seawater Pre-Treatment for Desalination (Current priority topic) This topic aims to optimize the VAL process as a pre-treatment step upstream of reverse osmosis in order to reduce fouling index (SDI), organic load, and fine particles. Research activities may include: flotation performance on real seawater, impact of the process on membrane protection and durability, hydrodynamic and energy optimization for large flow rates. A significant portion of the experimental work will be conducted on a VAL2000 pilot unit located in Palavas-les-Flots, enabling near-operational testing conditions. Topic 2 – Scale-Up & VAL Column Geometry (Core industrialization topic) This topic focuses on the scientific development and validation of a new generation of large-diameter VAL columns (>2 m), designed to multiply treatment capacity by a factor of 3 to 4. Research may include: hydrodynamics of vacuum air-lift columns, mechanical behavior under vacuum conditions, flow modeling (CFD depending on profile), flotation efficiency and concentrate extraction. This work constitutes a central pillar of VAL’s industrial capacity expansion strategy. Topic 3 – Treated Wastewater Reuse (Water Reuse / TWWR) (Exploratory and adaptable topic) Depending on project opportunities, partnerships, and candidate interest, a third topic may focus on treated wastewater reuse. This may include collaborative projects (e.g., UV technologies) to study: positioning of VAL as a tertiary treatment step, synergies between vacuum flotation and disinfection, water quality enhancement for reuse applications. This topic may be further developed, reoriented, or replaced depending on Coldep’s R&D priorities. Scientific Responsibilities Integrated within Coldep’s R&D team, the postdoctoral researcher will be responsible for: Designing and conducting experimental campaigns on pilot and demonstration units Acquiring, processing, and analyzing experimental data Physico-chemical and hydrodynamic interpretation of results Writing scientific and technical reports Contributing to scientific and technological valorization (patents, publications, conferences) Beyond the identified topics, the postdoctoral researcher will contribute to: Structuring scientific R&D programs Identifying key technological bottlenecks Proposing new research directions directly aligned with industrial needs Occasional travel (France and international) may be required for pilot testing, industrial collaborations, or scientific partnerships. Your Profile PhD in Process Engineering, Chemical Engineering, Water Sciences, Hydrodynamics, Physical Chemistry, or related field Strong interest in applied experimental research Solid analytical and scientific synthesis skills Experience in water treatment processes, flotation, mass transfer, membranes, UV treatment, or CFD modeling would be appreciated Autonomy, scientific rigor, and ability to work on transversal and evolving topics Proficiency in both French and scientific English Research Environment This postdoctoral position lies at the interface between academic research and industrial innovation, offering: Access to pilot-scale facilities and real operational data Scientific challenges directly connected to concrete industrial applications A strengthened ecosystem through integration into an international water technology group Application Candidates are invited to submit: A detailed CV A cover letter specifying their scientific interests and positioning with respect to applied and evolutive R&D Contact details of academic referees. Please send it to rh@coldep.com