The how, what and where of process mineralogy

Welcome to the new addition of the MinAssist blog, to be known as ‘Process Mineralogy Today’.  This blog has been developed by MinAssist to promote the use of process mineralogy within operations and as a forum to promote discussion on the most effective ways to achieve this.  I encourage you as the readers to comment on the ideas presented and add your comments on where you see process mineralogy going in today’s industry.

I started MinAssist in 2006 as a resource to tap into the resurgence of process mineralogy in the mining industry.  This had been catalysed in part by the emergence of automated mineralogical analysis systems, such as QEMSCAN and MLA, and by the continued development of online analysis options.  Through MinAssist and an association with Intellection Pty Ltd, working on applications for QEMSCAN, I have seen more and more large mining companies embrace process mineralogy and explore the potential that new technologies can bring.  Often this has led to solutions that were impossible using manual mineralogical tools. In turn this has opened up whole new areas where understanding the mineralogy of a material can have a significant impact on the nature of a solution.

In this first article I would like explore what process mineralogy has been, what it is today and ask for some feedback on how it is perceived.  This will lead to an exploration of all the aspects of process mineralogy over a series of articles.  The aim of this will be to promote some discussion on where you, the reader use process mineralogy or see it being used.

So what is process mineralogy?  To properly understand where it may be best applied, a comprehension of what we are dealing with is obviously required.  In essence, process mineralogy is the application of mineralogical information to help provide solutions in metallurgical or mineral processing programs and processes.  The mineralogy of a material comprises the basic building blocks of that material and consequently how it will behave.  The chemical composition, which is most often analysed, provides an insight into what makes up a material.  However, the minerals that these elemental building blocks form define how it will behave in different processes.  This is an important definition because it provides the basis for just how useful process mineralogy can be in mineral processing.

Take the example of a newly discovered copper-gold deposit.   Initial chemical assays might suggest that there is an average of 5 g/t gold and 5% w/w copper, along with some sulphur and a host of other elements.   This is a very prospective deposit but it is not until we look at the mineralogy to see how the copper occurs and what the gold is associated with that we can identify whether a viable process can be determined.  The minerals present will define everything from the process to be used; potential environmental impacts and even in some cases the mining methods.

So with that very short and incomplete introduction to process mineralogy, where and how can it be used?  The answer is that almost all stages of the mine life cycle can benefit from greater use of process or applied mineralogy.  Starting from the exploration and pre-feasibility stage of a project, right to clean-up and environmental monitoring long after the mine has shut down a comprehensive understanding of the mineralogy can add significant value to a project.  Over the next few articles I will explore the various applications of process mineralogy, how it can be applied at each stage of the mine life cycle and ways it can add value or save money.  A recurring theme I will focus on is that for all these applications undertaking mineralogical analysis early in the analysis process can greatly aid with understanding of results and promote efficiencies in all the subsequent testwork.  While this requires an additional step early in the testwork program it can save money through elimination unnecessary testwork at a later stage.

The core areas that I will examine of this series of articles will include the use of process mineralogy in:

1. Mineral exploration
2. Process evaluation
3. Pilot plant optimisation
4. Ore characterisation
   1. Ore typing and geometallurgy
5. Process and unit operation audits
6. Troubleshooting and risk reduction
7. Tailings evaluation
8. Environmental analysis
9. Integration with metallurgical testwork programs

This will roughly follow the life cycle of a typical development or mining project.  I encourage you to think about where you use process mineralogy currently and whether there are areas where you think it could be useful.  Let me know your ideas and if there are any topics that you would like me to specifically address.  If you are looking for any more general information then you can find it at MinAssist.com.au.  I look forward to your comments and hope you find the information presented useful and informative.