Method and facility for continuous aeraulic separation of particulate materials consisting of a mixture of particles heterogeneous in both particle size and density

A method for continuous aeraulic separation of particulate materials consisting of a mixture of particles that is heterogeneous in both particle size and density, the method comprising:

• (a) grinding initial particles of materials,
• (b) generating a gas stream conveying the ground particles,
• (c) first aeraulic separation on said gas stream in a first aeraulic separation unit in order to separate the particles contained in the first aeraulic separation unit into a first fraction consisting of coarsest particles with variable densities, and a second fraction consisting of finest particles,
• (d) second aeraulic separation on said first fraction in a second aeraulic separation unit in order to separate the particles contained in the second aeraulic unit into a third fraction consisting of coarsest and/or densest particles and a fourth fraction consisting of least coarse and/or least dense particles,
• (e) reinjecting the third fraction to an inlet of the grinding to recover the second fraction comprising particles of the finest particle size with an increased proportion of metallic materials relative to the initial particles, and reinjecting the fourth fraction comprising particles of the coarsest and least dense particle size with an increased proportion of non-metallic materials relative to the initial particles, and
• (f) simultaneous recovery of the second fraction as well as the fourth fraction or the third fraction, respectively, as output products.