METHOD FOR REMOVING INORGANIC CONTAMINANTS FROM SOILS VIA A PHYSICOCHEMICAL EXTRACTION TECHNIQUE.

摘要

A method for decontaminating soils that are contaminated with an inorganic contaminant, comprising: screening the contaminated soils in order to obtain coarse and fine fractions; sieving the screened soils in order to retain therefrom the coarse fractions and, concurrently, washing the screened soils in order to obtain a first effluent comprising the washing liquid and the fine fractions flowing from the sieve and comprising fines and particles with dimensions greater than those of the fines; separating the fines from the first effluent in order to recirculate fresh water and thus obtain a second effluent; ensuring the supply of the washing operation; and conveying the contaminated fines separated from the first effluent to a chemical chamber where a portion of the first effluent and a chemical solution are added in order to produce a third effluent (acid), the latter containing metals dissolved in the fines that it is necessary to separate. The fourth effluent comprises the fines and a precipitation of this effluent is produced in order to extract the precipitated contaminants, so as to obtain a fifth effluent, whereby the inorganic contaminant is extracted and it is possible to reuse the fifth effluent for recirculation in the treatment process.