Supply potential, carbon emission reduction, energy conservation, and sustainable pathways for aluminum recycling in China

Abstract

Achieving low carbon emissions in the aluminum industry is greatly dependent on supply-side recycling, but recycling potential and benefits remain unclear. This study aims to explore proactively the long-term transition pathways for China's aluminum industry under the influence of multiple factors, by using top-down material flow analysis and Weibull distribution which quantifies aluminum stocks and flows across various sectors from 1978 to 2060 and then projects the recycling potential, energy conservation, and emission performance under 18 potential scenarios which accounts for social development, process changes, and production patterns to support sustainable pathways aligned with climate targets. The findings underscore the importance of transportation and infrastructure sectors, as well as demographic trends, in driving China's aluminum demand, with in-use stocks peaking between 2034 and 2045, contingent upon population dynamics. The increasing availability of scrap material necessitates enhanced recycling for sustainable resource utilization. Scenarios 6, 12, and 18 (durable products, a 5 % growth in secondary aluminum) show that secondary aluminum can fully meet China's needs, driven by high recycling rates that address supply challenges and yield substantial energy and carbon reduction. The optimal scenario 6 illustrates cumulative CO₂ mitigation of 21.28 Gt and power savings of 9.03 PWh by 2050, which could even support the _1.5DS-China target. The longevity of end-of-life products significantly impacts secondary supply proportions. The short-flow processes for secondary aluminum are essential to the industry's climate commitments.