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Heavy metal contamination of the environment could pose health risks to humans. Until recently, several geochemical routes were considered to address the issue of metallic leachates from sources such as e-waste deposal sites or mining areas. Following the adsorption pathway, this study focused on investigating the ability of calcination products as a low-cost option for the remediation of zinc contaminated effluents. Sediments dredged in northern France were calcined by flash calcination method, before testing the calcination products (FCS750 hereafter) as adsorbent for zinc removal. The calcination process performed at 750 °C resulted in a denser material with a higher specific surface area and lower organic matter content, suited for aqueous remediation. Kinetic and equilibrium assessment underlined a rapid adsorption better described with the Pseudo Second Order model than the Pseudo First Order or Bangham equations. Adsorption models (Langmuir, Freundlich and Temkin) implemented to describe the interaction under two pH conditions (pH = 2; pH = 7) resulted in a maximum adsorption capacity (qmax) of 89.61 mg g−1 under the most favourable configuration. The pH conditions had poor influence on the adsorbing capacity value, which suggested a good buffering property of the calcined sediment and a potential applicability on effluents with different chemistries. A qmax comparison based on 42 studies indicated that FCS750 was more beneficial than most raw organic adsorbents but remained less effective than grafted and composite materials. Nevertheless, the low number of steps necessary for FCS750 processing, the easy access of its precursor (harboring wastes) and its low energy cost suggested good economic competitiveness and pleaded in favor of field experimentations.

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The dredged sediment has been positioned for years as alternative materials in the construction field. However, it is often necessary to apply a treatment to improve their reactivity and performance. This article aims to study the pozzolanic reactivity of fluvial sediment treated by flash calcination method at different temperatures 650 °C, 750 °C, and 800 °C. The physico-chemical, mineralogical, and environmental characteristics were studied for treated (flash-calcined sediment) and raw sediment. The pozzolanic reactivity of the flash-calcined sediments was estimated with Frattini’s test, isothermal calorimetry test, lime consumption analysis and compressive strength then compared to metakaolin which is considered as the reference. The results of the compressive strength of mortars show the detrimental effect of raw sediment on the development of resistance. Contrary to the raw sediment, the treatment of the sediments by flash calcination activates the pozzolanic reactivity of the clay phases and considerably improves the contribution of the sediments to the development of resistance and the porous structure. Moreover, the sediment calcined at 750 °C gives better properties than those obtained at 650 °C and 800 °C. The result demonstrates the feasibility of using calcined sediments as a pozzolanic mineral addition in a cementitious material.