Assessing Organic Matter of Port Dredged Sediment for Valorization in Civil Engineering

To ensure proper navigation and safety levels, over one billion cubic meters of sediment are dredged yearly from ports around the world. Beneficial use of port dredged sediment, considered as waste, is a potential alternative for the large quantities of natural resources required in civil engineering. It can solve a joint problem; environmental impacts of dredging and the scarcity of non-renewable materials used in the construction industry. Assessment of the organic matter is a decisive step within the process of valorization, in order to determine the port dredged sediment characteristics and confirm the feasibility of its reuse in the construction sector. The sediment is made up of water, inorganic and organic materials and compounds of anthropic origin. As a substitute of construction material, the presence of organic matter can affect the properties and the behavior of dredged sediment. However, existing research efforts on reusing dredged sediment in civil engineering rarely analyzed organic matter content. Moreover, they relied on the results obtained on the basis of a given method without confirming their findings by other means. This paper, having as main objective the investigation of the possibility of reusing dredged sediment as a substitute of conventional construction aggregate, fills this gap. Organic matter analysis were carried out by chemical method and calcination method. The two methods were applied on numerous samples collected from the port of Safi in Morocco during 2022 dredging campaign. The results of the study reveal that the organic matter levels of dredged sediment are below the reference values. Thus, valorization of dredged sediment in civil engineering is feasible. This study provides valuable information for achieving the sustainable development from waste to resource.