Environmental benefits of secondary copper from primary copper based on life cycle assessment in China.

China is the largest producer and consumer of refined copper in the world. The large amount of copper consumption not only creates added pressure surrounding resource availability but also causes prominent environmental problems. Although copper can be recycled to alleviate resource pressure, there are significant differences between mining primary copper and recycling scrap copper in view of resources, energy consumption, and pollution emissions. These factors were analyzed to better understand the total environmental effects of refined copper from extracting primary ore and recycling scrap copper. The results of this analysis showed that the most serious environmental impacts of refined copper were human toxicity, abiotic depletion potential, and global warming potential. The environmental impacts were mainly caused by the mining and smelting of primary copper by pyrometallurgy. For secondary copper, refining and electrolysis were the main factors. Thus, these main processes, which cause major environmental impacts, should be promoted technologically. According to the results, the total environmental impact of secondary copper was only 1/8 that of the primary copper production process, which indicates that regeneration has better environmental benefits. Furthermore, the sensitive analysis showed that electricity was the most sensitive factor of both technologies. By optimizing the energy structure and increasing the proportion of regeneration, can also reduce the environmental impact. It was suggested that energy structure should be improved and secondary copper should be given more attention and be developed vigorously. Finally, ways to reduce the environmental impact of primary copper and secondary copper industries were recommended. [ABSTRACT FROM AUTHOR]