There are growing expectations of mining companies to operate in a more sustainable manner, with a strong business case for improving waste management and reducing environmental impacts. As the stewardship of tailings come under increasing scrutiny, decision-makers are urged to adopt a robust approach to the selection of a tailings management strategy that encompasses design for closure, and leading practices to lower the risk of catastrophic dam failures, optimise the use of resources, and mitigate environmental impacts on climate change. An integrated analysis, considering economic, environmental, social, and risk aspects of the operation can therefore provide decision-makers with balanced information to ensure the right projects proceed with an optimal business case so that the most cost-effective solution, that does not externalise costs, can be selected. However, literature review revealed that fundamental shortcomings exist within traditional evaluation approaches used for economic comparisons. This paper reports on life cycle cost analyses conducted for comparing various tailings management options under different scenarios. A conceptual case study for the disposal of gold tailings in Western Australia as a slurry, as thickened, or as filtered tailings, was considered. This was done for examining the extent to which potentially hidden costs impact on the total cost of a project. It is suggested that the proposed approach will lead to selection of a tailings management alternative that ensures sound economic, environmental, and social performance is achieved.
This paper covers FLSmidth KREBS® pump development, over the past 10 years, of an extensive range of highpressure centrifugal slurry pumps for multistage applications. The primary objective has been to produce safe, economical, energy efficient and maintenance friendly centrifugal slurry pumps to fulfil the expanding requirements of the mineral processing industries in the long distance transportation of tailings and mineral slurries. Two ranges of pumps have been developed, a double cased pump (based on the KREBS rubber lined slurryMAX XD pump) and an unlined white iron cased pump (based on the millMAX pump). The logic behind the development of the two pump ranges will be explained in depth covering the design and first article production, getting it right. The methodology of the hydraulic and structural criteria requirements that are considered during the pumps design are integrated with the use of computational fluid dynamics and finite element analysis to ensure that the pumps perform safely, reliably and with maximum efficiency. Application of the pumps to projected operating data is explained taking into consideration specific needs for flange and foundation loads, maintenance and condition monitoring. Consideration of slurry rheology and its implication on pumping performance is discussed. Cost comparison between actual field data and the theoretical positive displacement (PD) costs, as presented at the 21st International Seminar on Paste and Thickened Tailings, will be analysed in the Appendix.
An Analysis of Impacts on Mine Planning, Land, GHGs, Costs, Site Water Balances and Recycle Water Chloride Concentrations. COSIA requested Norwest to develop generic models to examine the relative impacts of different FFT management processes on mining and tailings capital and operating costs (capEx and OpEx), reclamation and closure costs, and environemtnal impacts. The models were based on two virtual mine scenarios selected to represent a range of conditions typical of the surface mine sites of the Athabasca oil sands region.
Recent TSF failure investigation reports and other literature have emphasised the need to consider innovative means for tailings management to facilitate a reduction of risk, but it appears likely that improved safety performance of TSFs will not only be achieved through advances in design methods, but also in selection of storage options that seek to reduce the consequence of facility failure. To this end, strategic planning in which large horizons of time and varying inter-dependencies of the components that make up the tailings operation are considered is essential. While this is widely acknowledged, there are limited published examples of how mining companies apply strategic planning considering whole-of-life comparisons linking the integration of TSFs embedded within the mine plan. This paper presents a set of case studies where significant benefits have been or are being realised through the integration of long-term tailings and mine planning functions at Rio Tinto Iron Ore mine sites.
Until mid-2020, the Newmont Éléonore mine cemented paste backfill (CPB) recipes were chosen from charts comparing binder contents and strengths at specific curing ages up to 56 days. However, these charts were based on Mitchells method using Éléonores biggest stope dimensions. They also did not consider any rheology, maximum surface pump pressure capacities or mix density. Using the new system, and its resulting template, backfill personnel can tailor a recipe for each stope to meet the latest sequence and environment conditions. This paper explains how the new paste recipes are selected, as well as the costs savings and productivity increases they enabled.