Life cycle assessment of dredged sediment recycling as an eco-friendly construction material

This study investigates the environmental and economic feasibility of recycling dredged sediment into eco-friendly construction materials, focusing on the production of lightweight aggregates (LWA), cement (CEM), and lightweight concrete (CON). A life cycle assessment (LCA) was conducted using openLCA software with the CML 2001 method and Ecoinvent 3.7 database, evaluating six impact categories: global warming, acidification, eutrophication, human toxicity, photochemical oxidation, and ozone depletion potentials. A life cycle cost analysis (LCCA) using the net present value (NPV) method was also performed to assess cost efficiency. The results showed that LWA had the lowest environmental impact across all categories, achieving reductions of 63.8–99.9% compared to CEM and CON. CEM exhibited the highest environmental burden due to CO₂ emissions from clinker calcination, while CON was mainly affected by carbon monoxide emissions. Monte Carlo simulations confirmed the reliability of the LCA outcomes, and sensitivity analysis identified transport distance as the dominant factor in ozone-depleting emissions. Although LWA production involved higher energy costs, especially from natural gas use during sintering, it met key environmental and mechanical performance standards, supporting its applicability in ESG-focused and ISO 13055-compliant construction markets. Overall, this study concludes that recycling dredged sediment into LWA provides substantial sustainability benefits, offering a promising alternative to landfilling and conventional aggregate use.