An evaluation of an integrated screening and particle sorting grade engineering flowsheet

Wilkie, Keeney, Walters, Dyer, Tadesse

Published in Proceedings of the IMPC2020 Congress, SAIMM


Grade Engineering® is a term trademarked by the Cooperative Research Centre for OptimisingResource Extraction (CRC ORE) and includes five key levers for upgrading ores and rejecting waste prior to expensive downstream comminution and mineral processing. These five levers include natural deportment, induced deportment, bulk sorting, particle sorting and gravity separation.

Over the past ten years, CRC ORE has progressed a range of technologies that exploit these levers from laboratory proof of concept through to large scale demonstration and validation.

This paper details the work carried out by CRC ORE and Curtin University for assessing the amenability of an ore for its natural deportment and particle sorting attributes in an Integrated Screening and Particle Sorting (ISPS) Grade Engineering® process. ISPS is seen as a preferred method for Grade Engineering® as compared to individually operated unit operations as the benefits of each can be complementary. Furthermore, it is suggested that integrating the two levers has two important impacts: 1.Firstly, there is a risk that isolated particle sorting test results will be misinterpreted as being representative of the full sample without considering the mass balance impact of high-grade material that might have been lost in the fines fraction. This fine fraction will not be detected through the particle sorter. 2.Secondly, and potentially of more valuable impact, is that the opportunity may exist to upgrade the feed first through determining if there is a concentration of high grade to the fine (or coarse) fraction which can be separated throughscreening.

Undertaking screening in the preparation stage of the particle sorting process will enable analysis and separation of the fine or coarse fractions of a rock mass.The result of this study provides the mining industry with an independent framework for undertaking an Order of Magnitude (ISPS) Grade Engineering® assessment on a range of constituent ore types.Keywords: Grade engineering, particle sorting, grade by size fractionation


G.J. Wilkiea*, L. Keeneya, P. Waltersa, L Dyerb,and B Tadesseb

aCRCORE, QCAT, Technology Transfer Centre, 1 Technology Cout, Pullenvale, 4069 QLD, Australia

bWestern Australin School of Mines,Minerals Energy and Chemical Engineering, Curtin University, 95 Egan St.,Kalgoorlie, WA 6430, Australia

*Corresponding author: This email address is being protected from spambots. You need JavaScript enabled to view it.


The authors acknowledge the Cooperative Research Centre for Optimising Resource Extraction (CRC ORE) which provided funding and resources for this research. The authors would also like to thank the staff and students of Curtin University who assisted in the logistics and sampling of the ores used to demonstrate this new frame work.

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