Geometallurgy modelling: the Good, the Bad, the Ugly

Speakers:  Matthew Nimmo and Andrew Millar, AMC Consultants

Abstract:  In the not-so-distant past, mine planning and scheduling, strategic optimisation, short term scheduling and ore control relied on average estimates of rock performance through the crushing and grinding circuit and the process plant. Geometallurgical modelling, adding comminution (rock hardness, Axb, BBMWi) and processing response (mass recovered, concentrate grade and metal recovery) to a geological block model, replaces average values with spatial estimates (the Good). Geometallurgy modelling also allows for spatial estimation of a value descriptor (NSR) and can be used for blending studies and assist with sampling to continuously improve the model. The success of the geometallurgy modelling study is dependent on the quality and distribution of the data. Any data biases can result in a model that is very inaccurate (the Bad). However, one of the biggest threats to a geometallurgy study is the people and their cognitive bias (the Ugly). This talk will explore the Good, the Bad and the Ugly in geometallurgy modelling.

Bios:  Matthew Nimmo has nearly 30 years of experience in the mining industry as a resource geologist and data scientist. He is experienced in all facets of data analysis and machine learning. He has worked for Newcrest Mining, Harmony Gold, WMC, Hatch, Golder and AMC and recently spent 2 years working in the BHP Mining Centre of Excellence supporting the Total Equipment Strategy (TES).  At AMC, Matthew is involved with Mineral Resource estimation and predictive Geometallurgy modelling and mining data analytics. He is proficient with mining software and R for data analysis, statistics, variography and modelling.
Andrew Millar is Principal Metallurgist at AMC Consultants. Andrew has over 19 years in the mining industry and is experienced in the mining project life cycle from discovery to operations. Andrew’s expertise includes designing and managing metallurgical testwork programs, process flowsheet design, geometallurgical studies, process engineering, project management, feasibility studies, plant operations and techno-economic modelling. Prior to AMC, Andrew worked for Core Resources, SKM and GRD Minproc in addition to the Mopani gold operation in South Africa, the Wilkie Creek coal operation, the Risdon zinc smelter and the Kestrel coal operation. Andrew is a Chartered Professional (Metallurgy) for the AusIMM and is RPEQ accredited.