This study assesses the Novosol~? process, an emerging technology developed by Solvay to treat heavy metals from dredged sediments using phosphoric acid. The main goal is to convert toxic metal ions, such as Pb~(2+), Cd~(2+), Zn~(2+) and Cu~(2+) to insoluble metallic phosphates. The effectiveness of the treatment was evaluated by performing the chemical reaction in a tubular reactor, followed by convective drying and maturation of the treated sediment at ambient temperature and finally thermal destruction of the organic matter by calcinations (500°C-700°C). Selected variables (acid concentration, volume fraction of solids, flow rate, drying and calcination temperature and time) were investigated. Laboratory scale experiments were carried out with various combinations of these parameters.The influence of the quantity of acid and the temperature of calcinations on physical properties of the sediment and stabilization of the heavy metals are discussed.
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