Glass Waste3: A Preliminary Study for a New Industrial Recovery Processing

Abstract

In recent times, the selection and treatment of glass waste are implemented in processing plants where a secondary raw material (SRM) named glass cullet, which is suitable for glass production, and a waste containing a high percentage of glass (glass waste2) is obtained. In the literature, there are many studies conducted on the recovery of the cullet, while few are the studies on the recovery of the waste that is produced by cullet processing. According to the 2013 Joint Research Centre (JRC) Reference report, the cullet produces savings in terms of energy and raw materials. However, it has a high current cost and its availability is becoming difficult, therefore its use is not always economically advantageous. The goal and strategy of the European Union is zero waste. For this purpose, further treatment of glass waste has been investigated. Through the industrial treatment of the glass waste2, a glass waste3 constituted again by an SRM made of glass is obtained together with a high quantity of presumed SRM (e.g., heavy plastic, corks, iron, non-ferrous metals, etc.). The process treatment separating these SRMs from the glass waste3 is, in this case, a pilot plant that needs to be optimized in order to reach an economic and sustainable industrial process solution. In particular, the materials to be recycled are exploitable product fractions with different particle sizes and physical properties (such as density, shape and resistance). This research is based on data collected from a North Italy process plant and is aimed at solving the issue of waste in this kind of process by implementing a pilot plant already present. Representative samples of feed material (glass waste3) and different products of the pilot plant have been analyzed. Moreover, laboratory tests were executed to improve separation efficiency and to valorize the different product fractions. A flow sheet of a new treatment plant has been developed and an economic evaluation has been made. The materials that will be separated in the new plant could be traded as SRM—e.g., plastics, metals, synthetic and cork stoppers—which constitute almost 90% of the total feed of the plant.