Abstract: Granular substances with pollutants adhered, such as contaminated soils and incinerated ashes, are finely granulated to separate the pollutants from the granular substances efficiently and to enable the granular substances, from which pollutants have been separated, to be recycled. After fine granulation of the granular substances by a coarse disintegrating treatment through a first fine granulation machine, the granular substances, which have been finely granulated by the first fine granulation machine, are subjected to, by a second fine granulation machine, mutual polishing among the granular substances by mutual rubbing forces of the substances themselves and thus the pollutants, such as heavy metals and dioxin class substances adhering strongly to the surfaces of the granular substances, are separated, and also the granular substances not containing the pollutants are classified from the granular substances which have already been finely granulated by a vibrational screen and a classification device.