Mechanism of Salt's Surface Crystallization at Djègbadji Salt Marshes, Benin (West Africa)

Salt production, a key component of the local economy, relies on complex natural processes, particularly capillary rise and surface crystallization. In Djègbadji, Republic of Benin, salt is produced by boiling brine, which is obtained through the leaching of salt-laden soils. Although this traditional method has been practiced for generations, it is highly dependent on the hydrodynamic properties of the environment and the specific characteristics of hydromorphic soils, which influence the movement of water and salts. In these salt marshes, the interactions between water, soil, and air play a crucial role in salt formation and concentration. However, a detailed understanding of the underlying mechanisms remains a scientific challenge. This study employs theoretical and experimental approaches to analyze these phenomena. The one-dimensional Terzaghi equation is used to model the interactions between soil parameters and capillary forces, while the Navier-Stokes equation is applied to examine salt crystallization. These tools provide a deeper insight into the physical dynamics governing this unique ecosystem, enabling a better understanding of water and salt migration. By integrating numerical modeling, this research aims for a sustainable optimization of salt production techniques. The expected results will contribute to better resource management, while offering perspectives for improving local salt production and its adaptation to current environmental challenges.