Method of recovery of precious metals & heavy minerals

摘要

Raw material containing precious metals and heavy minerals is introduced into a comminuting chamber. The raw material falls onto rotating chains which drive the material against the side wall of the chamber with sufficient velocity to cause the raw material to fracture. Air flows upwardly at the side wall and classifies the particles into a first fraction which falls to the floor of the chamber and a second fraction which is carried upward to a trommel. Large particles from the trommel are recycled to the chamber while fines are discarded as tailings. The rate of upward flow of air in the chamber, the rate of rotation of the chains and the size of particles separated by the trommel are all adjusted in order to ensure that the particles that collect on the floor of the chamber are rich in precious metals and heavy minerals.