CHAPTER 9: Mining Municipal Waste: Prospective for Elemental Recovery

Waste is an ever‐increasing challenge in all corners of the globe as populations and material consumption increase. At the same time, global consumption of metals is predicted to increase five times by 2050, with industrialised nations currently using 5–10 times more than developing countries. Unless ways are found to value ‘waste’ and create a ‘closed loop’ materials economy there is little chance of achieving elemental sustainability or equitable distribution of resources. This chapter explores the challenges and opportunities for mining municipal waste with an emphasis on metals and particularly precious and speciality elements. Current elemental stocks contained in society and how they flow into waste are discussed as well as the technological and social difficulties of accessing these stockpiles. The potential for urban mining from areas such as landfill and waste incineration ash are considered along with analysis of techniques for retrieving elements from these sources. A current example of urban mining in action, through the retrieval of Pd and Pt from road sweepings, demonstrates the potential of previously considered ‘waste’ as an elemental feedstock.