| About this Abstract |
| Meeting |
2023 TMS Annual Meeting & Exhibition
|
| Symposium
|
New Directions in Mineral Processing, Extractive Metallurgy, Recycling and Waste Minimization: An EPD Symposium in Honor of Patrick R. Taylor
|
| Presentation Title |
Electrochemical Mining of Municipal Solid Waste Incinerator Ashes |
| Author(s) |
Michael Wang, Duhan Zhang, Yet-Ming Chiang |
| On-Site Speaker (Planned) |
Duhan Zhang |
| Abstract Scope |
Disposal of society’s trash is an environmental concern towards which municipal solid waste incineration (MSWI) plays a mitigating role by reducing landfill volumes and generating electricity. However, the economics of MSWI are increasingly challenged by the decreasing cost of renewable electricity. Meanwhile, MSWI ash represents an untapped resource for valuable materials, with embodied value ranging from $100-400/tonne. Here, we propose an electrochemical process for mining MSWI ash which uses MSWI electricity to electrolytically produce acid and base reagents for metals extraction and recovery. We demonstrate a process sequence that uses electrowinning and hydroxide precipitation to recover elements including Cu, Pb, Zn, Fe, Al, Mg, and Ca, with a purified silica co-product. Recovery of >90% of the targeted elements, at purities >90% for most elements, is demonstrated. Techno-economic analyses show that the proposed process provides net economic returns exceeding that from the current model combining electricity sales and ash landfilling. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Recycling and Secondary Recovery, Extraction and Processing, Sustainability |