A plant for recovering and treating residues from crushing scrap is provided. The plant includes a first plant part and a second plant part. The first plant part is provided with crushing and separation means configured to extract ferrous materials, non-ferrous metals and plastic materials from the residues from crushing. The separation means are provided with a granulator system configured to reduce, in dry mode and without pre-screening stages, the residues from crushing into a stream of granular material. The second plant part is provided with means to treat and size the plastic materials configured to transform the plastic materials into additive material to be used, in particular, in iron and steel plants such as blast furnaces, electric arc furnaces or suchlike. The means to treat and size the plastic materials includes a dry system for cutting and/or grinding the plastic materials.