Établissement d'une méthode de caractérisation minéralogique décrivant les sols contaminés par le plomb

Abstract

Many metal-contaminated soils originate in old abandoned industrial sites. One of the problems encountered in the reclamation of soils lies in the selection of the decontamination techniques. Few data are available to predict the efficiency of the extraction of metals from the contaminated soils. Moreover, a signifiant part of the contamination is often found as particles. These can be extracted from the soils by means of mineralurgical separation techniques. A trial and error procedure is often used for selecting the technique and the procedure parameters. The purpose of this study is to develop a method of mineralogical characterization for the identification and localisation of the metal contamination so as to allow a more enlightened choice of the mineralurgical treatments. Besides the identification of the contaminant particles, the method takes into account the distribution of contaminants, which can be found on the surface of the particles or included within the volume of the particle, the average proportion and the size of the contaminants in the contaminated particles, and the association of the iron oxide contaminant. The frequency of appearance of the particles depending on the different categories of the method guides the choice of the treatment technologies to be used so as to optimize the extraction of contaminant particles.Key words: metals, contamination, soils, lead, mineralurgical techniques, mineralogy.[Journal translation]