Academic Awards 2025 booklet

39 Development of NMR Methods for the Study of Marine Sediments Every year, tens of millions tons of sediment is dredged from European harbors and rivers, costing society billions of euros. Often treated as waste, this material—mainly composed of clay—has the potential to be reused as a cost-effective and sustainable building material. To unlock this potential, we must better understand the material properties of these sediments. This research explores the use of Nuclear Magnetic Resonance (NMR or MRI), a non-invasive imaging technique, to study how sediment settles and compacts over time—a process known as sedimentation and consolidation. Two new NMR-based methods are developed to measure sediment material properties: The first method develops a fast multi-slice NMR imaging protocol. It achieves high spatial resolution while reducing measurement time by a factor of ten, allowing detailed observation of how sediments evolve in the early stages of settling [1]. The second method focuses on determining pore size distributions, a key property for assessing material quality. By deriving surface relaxivity —an essential NMR parameter— it offers a non-destructive alternative to traditional techniques that destroy the material upon measurement [2]. Together, these methods provide powerful tools to analyze marine sediments (‘sludges’) without damaging them, paving the way to transform this abundant waste stream into a valuable construction resource. [1] Hol, N. J., Pel, L., Kurvers, M., & Chassagne, C. (2024). Fast 1D NMR imaging of clay sedimentation using a multi-slice stepper motor method. Experiments in Fluids , 66(1). https://doi.org/10.1007/s00348-024-03937-3 [2] Hol, N. J., Myouri, I., Chassagne, C., & Pel, L. (2025). Determination of the surface relaxivity of soft sediment using particle size and shape. Journal of Magnetic Resonance Open , 100198. https://doi.org/10.1016/j.jmro.2025.100198 Figure 1: The experimental MRI setup used to quantify soil properties. Figure 2: The sedimentation process of marine sediment, with the MRI technique used to quantify soil properties.