Comparison of Three Emerging Dross Recovery Processes in China’s Aluminum Industry from the Perspective of Life Cycle Assessment
Xueyuan Zhu, Qiang Jin
Abstract
As a hazardous waste, secondary aluminum dross has troubled the aluminum industry for many years. A coupled life cycle assessment and life cycle costing method was used to evaluate the environmental impacts and economic cost of three emerging processes for recovering secondary aluminum dross in China. The results showed that the ball milling scenario had the smallest environmental impacts, and the alkali scenario had the highest economic profit. These findings could be attributed to the more than 70% lower environmental burden in the ball milling scenario and the alumina worth 1574 ¥ in the alkali scenario. The deactivation of aluminum nitride was found to contribute approximately 29.0–45.0% of the environmental burden and only 5.2–9.7% of the profit. Prerecovery of metal aluminum and use of hydropower were highly recommended. The development of the secondary aluminum industry may help reduce the environmental burden of the three scenarios by 5.8–19.6%, but the difficulty of residue treatment was found to be increased. On the basis of the dilemma of China’s aluminum industry and the development trend of dross recovery, suggestions for the aluminum industry and its governance are proposed.