Ammonia Hydrometallurgy and Other Innovations for Sustainable Management of Waste Incineration Fly Ash

Abstract

Better waste management for waste incineration ash is a pressing need. Disposal sites for hazardous waste are being filled up by incineration ash, and opening new sites is difficult. Meanwhile, valuable resources in the ash are lost to landfills. This research explores innovative ways to turn incineration ash into a valuable resource. First, the researchers have developed methods using ammonia hydrometallurgy to selectively extract up to 70% of the copper and 50% of the zinc from the ash - the most valuable metals in the waste. Second, the metal extraction process is proposed as part of a comprehensive waste utilization scheme, including salt recovery and using the final waste as cement clinker raw material. The chemical variability of waste incineration ash is quantified, both over time and by origin, using a large database from industry. This addresses the challenges of variability when working with secondary resources. The metal resource potential is estimated, and fly ash characteristics are presented. The research paves the way for potential new fly ash waste management processes where waste is not just disposed of, but actively transformed into useful products, benefiting both the environment and the economy.