Polluted river sediments from the North region of France: Treatment with Novosol® process and valorization in clay bricks

Zoubeir Lafhaj (1) , Mazen Samara (1) , Franck Agostini (1) , Linda Boucard , Frédéric Skoczylas (1) , Guy Depelsenaire

1 LML - Laboratoire de Mécanique de Lille - FRE 3723

The paper presents results of studies on the valorisation of polluted river sediments from the North region of France. The first objective of this study is to validate the treatment of polluted sediments with the Novosol® process. This process is based on the stabilization of heavy metals in the solid matrix by phosphatation and the destruction of organic matter by calcination. The results of environmental tests carried out on treated sediments showed that polluted sediments became inert. In addition, the physical characterisations of treated sediments classify them as sandy silt. Thus treated sediments were used as a brick making raw material. The second objective of the study is to determine the optimal mix-design. Four mix-designs were studied with treated sediment ratio varying from 0% to 45%. Physical, mechanical and chemical properties of these bricks were evaluated. The results obtained indicated that sediment proportion is an important parameter in determining the brick quality. Increasing the sediment content resulted in a decrease of brick compressive strength (though it is still higher than that of standard brick) and a decrease of its resistance to freezing and thawing.

Mots clés: River sediments; Heavy metals; Phosphatation; Calcination; Clay bricks

Zoubeir Lafhaj, Mazen Samara, Franck Agostini, Linda Boucard, Frédéric Skoczylas, et al.. Polluted river sediments from the North region of France: Treatment with Novosol® process and valorization in clay bricks. Construction and Building Materials, 2008, 22 (5), pp.755-762. ⟨10.1016/j.conbuildmat.2007.01.023⟩. ⟨hal-00262214⟩