Toward Zero Waste Mining: Circular Economy of Copper Slags

Only 8.6% of the global economy follows the principles of the circular economy. Mining and metal extraction processes generate over 90% of global waste, with slags being the major contributor to waste accumulation. Copper slags mostly consist of stable compounds that are safe for the environment, the main concern being the leaching of heavy metals into the ground. The market for using waste copper slags to produce value-added products is established in the last century and grown to an 800 million dollar market in 2024, with a predicted compound annual growth rate of 5.5% in the following years. However, only 15% of the generated copper slags worldwide are used for commercial purposes. In order to attain complete reusability of copper slags, industrial techniques must be adopted to eliminate threats from heavy metals and other possibly harmful elements. Additionally, it is essential to establish a market that can sustainably handle all quantities of generated slag. This review highlights the properties that make copper slags suitable for producing value-added products. With the rapid increase in population and urbanization, there is a potential to utilize copper slags for a-large-scale construction purposes such as earthworks and buildings. The demand for geotechnical applications and construction materials constantly increases and can absorb the entire quantity of copper slags generated. If this happens, it would mean an achievement of 100% reusability of copper slags in compliance with circular economy principles.