NOVEL HYDRAULIC BINDER BASED ON SULFOALUMINATE CLINKER AND ITS USE IN A PROCESS FOR TREATMENT OF POLLUTED SOILS

摘要

The invention relates to a hydraulic binder based on a sulfo-aluminous clinker comprising the mineral phases Yeelimite C 4 A 3 $, Mayenite C 12 A 7, CaO free lime, and C 2 S Belite, characterized in that in said clinker the mineralogical phases are present in the proportions of 20% to 50% by mass phase Yeelimite C 4 A 3 $, from 5% to 80% by mass of Mayenite C 12 A 7 phase, and from 1 to 5% by mass of CaO free lime, from 10% to 40% by weight of C 2 S belite phase, the mass ratio between the Mayenite C 12 A 7 and Yeelimite C 4 A 3 $ phases being between 0.1 and 10, and the clinker comprising in addition a CaO phase, SO 3 (C $) up to 5% by weight. The binder may be used in a process for treating polluted soils, especially soils having a leachable fraction greater than 0.4%, the said leachable fraction containing mainly anions, in particular sulphate ions and / or chloride ions, and or cations of heavy metals, by mixing said soil with said hydraulic binder, in mass proportions sol / binder of between 1 and 40 parts of binder per 100 parts of soil. It allows the stabilization of polluted soils in situ or before landfill.