Abstract: A process and device for the treatment of waste substances for the purposes of recovering organic matter involving introducing, by a suitable mechanical device, the substrate of waste substances to be treated; opening, by thermal fusion, any various packages containing this substrate; separating the fine elements of this substrate by screening; selectively fragmenting the coarse residues from the first sizing; separating these residues by screening; separating all of the screened fragments by means of magnetic sorting; differentially wetting these screened fragments; sorting these fragments by differential rebound and aqueous adherence; and removing, by a mechanical device, the substrate of screened waste substances.