Techno-economic analysis of an integrated bio- and hydrometallurgical process for base and precious metal recovery from waste printed circuit boards

Electronic waste (e-waste) is one of the fastest-growing waste streams and is often referred to as an urban mine due to its high base and precious metal content. Printed circuit boards (PCBs) have been the focus of numerous studies investigating bio- and hydrometallurgical pathways to extract and recover metals of value. This study evaluated the economic feasibility of an integrated bio- and hydrometallurgical process for extracting and recovering base and precious metals from PCBs. The process consisted of collecting and processing PCBs, extracting and recovering base metals using biogenic sulfuric acid and ferric iron, and extracting and recovering precious metals using hydrometallurgical pathways. A preliminary techno-economic analysis (TEA) was conducted to examine the potential costs of a plant that can process 1,000 tons per year of PCBs in Australia. The key factors that influence the economic feasibility were identified, and the effects of various factors, such as process efficiencies and market conditions, on the plant's profitability were evaluated. This assessment provided insight into the economic aspects of the process and assisted in identifying critical research pathways. Based on this analysis, the proposed process is profitable under optimised conditions and can address many challenges associated with e-waste processing in Australia.