Process for the decontamination of toxic, heavy-metal containing soils

摘要

The present invention relates to the decontamination of soil and the like and, in particular, soils which are contaminated with metal as a result of the activities of human beings. The invention provides a physical and a chemical means for treating soil aggregate so as to obtain a product aggregate having a relatively low metal content. The physical means is characterized by the classification of a soil aggregate into portions of differing size and metal content. The chemical means is characterized by contacting a soil aggregate with an aqueous lixiviant comprising an organic acid component to lift metal from the aggregate. The physical and chemical means may be used in a combined process for decontaminating soil aggregate.