A practical and rigorous approach for the integration of sustainability principles into the decision-making processes at minerals processing operations

Abstract

In the mining industry, high-level commitments to adopt sustainability have been made at the corporate levels of mining companies, but there continue to be problems when attempts are made to adopt these high-level sustainability aspirations and translate them into appropriate targets and methods at the more-specific operational level. The integration of sustainability principles into day-to-day mineral processing operational decision-making processes has unique challenges that are not addressed adequately by current tools and methodologies.A proposed methodology to achieve integration of sustainability at the operational level will direct the systematic and rigorous identification and qualification of sustainability issues and opportunities in an operation. The methodology, starting from a sustainability point-of-view rather than an operational one, guides the identification of process issues (“problems”) and opportunities by examining the operation, unit-by-unit, similar to a HAZOP process. Each issue or opportunity is qualified according to its measurability, scopes of impact and consequences so that it may be understood fully and the correct engineering problems are formed.The methodology has been tested with two case studies at minerals processing operations. At one site, the methodology identified a dust issue which had considerable business risks (loss of valuable product) compared to conventional engineering analysis processes. The other site also benefited from using the methodology as an opportunity to improve the milling circuit between the semi-autogenous grinding (SAG) mill and flotation circuit was identified. The opportunity not only showed a potential to improve the operational efficiency of the units concerned, but also potential improvements in water and energy (both direct and embodied) efficiency. It was important to utilise the holistic approach of the methodology in the identification of opportunities at this site; the goals of the operation showed a strong coupling between water and energy issues which would be difficult to overcome using the operation’s current organisational model which deals with such issues separately of each other.