Early-stage design and development of mine waste valorisation technologies with expert input

Mining is essential for providing the minerals and metals necessary for modern life and the transition to renewable energy. However, mining activities generate substantial volumes of waste, leading to environmental degradation and health risks. Converting mine waste into valuable products through valorisation approaches will serve to eliminate these long-term risks and is aligned with principles of resource efficiency and the circular economy.

However, the unknown compositions, complexity and heterogeneity of mine waste, coupled with untested technological options, present significant challenges for technology design and development for valorisation. Additionally, transfer of unsolicited university- and research institution-developed technologies to industry can be difficult. To overcome these obstacles and support the development of sustainable waste management solutions at universities and research institutions, this paper presents a generalised approach for the early-stage design and development of mine waste valorisation technologies. The approach was developed by integrating chemical engineering design principles with technology development and innovation frameworks.

The paper then synthesises the outcomes of a larger study and three peer-reviewed papers which applied key components of the proposed approach to South African sulfide-enriched fine coal waste. Important outcomes and learnings from this application are discussed as well as the implications for future design and development of mine waste valorisation technologies. Key findings indicate that investigating technology transfer considerations early provides useful information for the design and development process and that expert judgement can be unreliable for decision support. Recommendations include exploring the use of a combination of expert judgement and pre-feasibility modelling for decision support.