Nowadays glassy sand, obtained from the secondary waste of glass, is well accepted by glass factories. However, a plant producing this kind of secondary glass generates 3% of waste (glass waste 3) made of all the impurities usually present in glass waste. In particular, the materials not recovered are represented by ceramics, stones, magnetic and non-magnetic metals, paper, plastics, cork, synthetic corks etc., which are not always easily removable Glass waste 3 is therefore made of exploitable product fractions with different particle sizes and physical (such as density, shape and resistance) properties. This research is based on data collected from the SASIL plant, and is aimed at solving the issue of the waste of this kind of process implementing a pilot plant already present. Representative samples of feed material (glass waste 3) and of different products of the pilot plant have been characterized and laboratory tests were executed to improve separation efficiency and to valorise the different product fractions. A new treatment plant has been designed and economic evaluation has been made. The materials to be traded as secondary raw materials (SRM) – such as plastics, metals, synthetic and cork stoppers – are near 90% of the total feed of the plant.