Environmental management and metal recovery: re-processing of mining waste at Montevecchio site (SW Sardinia)

The paper illustrates and discusses an innovative approach in the reclamation of old mining areas, which is inspired by the circular economy principle and considers the waste of old mining and mineral processing activities as secondary potential raw materials. The European Union legislation has been encouraging this type of practice, which is receiving full recognition from the international scientific literature as well. The application of the mining waste treatment as a reclamation technique is mostly based on the flotation technique that proved to be useful for separating the remaining minerals from the gangue. This provides both an environmental benefit and an economic advantage, which in some cases repays the re-processing costs, even though several difficulties could be encountered in the application of flotation to mining waste. The paper presents the results of the experimental laboratory batch tests, which proved to be encouraging in the case of the Montevecchio mining district (SW Sardinia). Nevertheless, future work is needed to clarify that they are valid for the different situations present on the site.