Synergistic environmental benefits from copper slag recycling in China: Pollutant mitigation and carbon reduction

In response to the dual challenges of climate change and environmental degradation, China is prioritizing efforts to manage both pollution and carbon emissions. Given China's leadership in global copper smelting, recycling substantial amounts of copper slag is considered a key strategy for environmental improvement. This study applies life cycle assessment (LCA) to evaluate the environmental benefits of three copper slag recycling strategies. Building on the LCA results, we introduced a synergistic reduction index system that assesses the combined effects of pollution mitigation and carbon reduction. Findings indicate that utilizing recycled copper slag in building materials not only significantly reduces local industry emissions but also demonstrates substantial synergistic effects. This strategy optimally reduces both air pollution and carbon emissions, largely due to the substitution of high-pollution materials with recycled copper slag. Based on these insights, we propose targeted recycling strategies tailored to regional needs and capacities, thereby offering practical suggestions for the sustainable management of copper slag.