Scenario analysis of the recycled copper supply in China considering the recycling efficiency rate and waste import regulations

The rapid economic growth and industrialization in China has induced a large copper demand since 1990, of which only approximately 40% is met by domestic ore deposits. However, a high dependence on imported copper ores, refined copper, or copper scrap can pose great risks to the sustainable copper resource supply and economic development of one country. An assessment of the in-use stock of refined copper is essential to estimate the potential supply of recycled copper, especially for countries with a high external dependence, such as China. A scenario analysis may further evaluate such a supply under different development pathways in the context of the increasingly strict import regulation of copper-containing end-of-use products. We introduced Material Flow Analysis and the Weibull lifetime distribution to estimate the in-use stock of refined copper from 1990 to 2035 in China based on the time-series data for sectoral refined copper consumption. The results show that the amount of generated copper scrap has been increasing from 1990 and reached 3.67 Tg in 2016, with 34.4% from the home appliances sector (mainly air-conditioning)and 26.6% from the power infrastructure sector. In 2035, the total would reach 17.7 Tg, with 42.8% from the power infrastructure sector and 19.7% from the home appliances sector. A scenario analysis was conducted considering different consumption growth rates, waste import regulation standards, and domestic recycling efficiency growth rates. The results show that under both scenarios, a total ban and limited imports of metal-containing scraps, the growth of the domestic recycling efficiency may improve the refined copper supply, which would be 0.867 Tg (67.4%)and 1.04 Tg (80.9%), respectively. With an adequate in-use stock of refined copper and an increasing recycling efficiency rate, domestic recycled secondary copper can cover the shrinking import source of copper scrap and become an essential source to meet the needs of the booming refined copper consumption in China.