Material Synergies and Industrial Symbiosis to Valorize Granite Scraps from Quarries in Sardinia
摘要
The OECD has projected a dramatic increase in the demand for primary mineral resources in the upcoming decades, with the potential to reach a value of 3.6 trillion tons by 2060. Consequently, the availability of primary materials will gradually decrease, resulting in a steady rise in market prices. Out of the 333 million tons of stone minerals extracted worldwide in 2021, approximately 70% of them will become waste material, and then in the coming years, the mining industry needs to focus on the principles of resource circularity and the value of secondary raw materials. Waste is still perceived as a problem rather than a potential resource: virtuous processes of recovery, reuse, reduction, and waste valorization would allow reducing the environmental pressure of mining activities. Quarry areas are sometimes adjacent to built-up areas, almost like an ‘ecological’ extension of them, causing severe environmental impacts that alter the quality and landscape perception of the man-made system. The paper presents the first evidence of a research and development project co-funded by the Ministry of Made in Italy Enterprises, carried out together with companies in the ceramic industry (where granite waste is valuable as raw secondary material), mining companies, and some Italian universities. To make good use of the large amounts of granite scraps found in the quarry landfills, researchers have explored the possibility of creating industrial symbiosis scenarios on a local district level. This research is specifically focused on the Buddusò-Alà dei Sardi (SS) in Sardinia, which is the largest granite quarrying basin in Italy. The aim is to establish one or more supply chains that can convert granite scraps into a valuable resource rather than a problem. Georeferenced surveys were conducted to determine waste volumes, types, and movement methods for activating symbiotic supply chains in the stone district. The analysis of waste volumes and sizes enabled prediction of reuse possibilities, including innovative on-site processing and marketable by-products. This scenario presents an opportunity to significantly decrease the current volume within quarry areas. This could lead to a redefinition of the environmental landscape while simultaneously establishing a production chain that optimizes the abundant supply of raw-secondary materials available on-site, promoting resource circularity.