Communication – the new mining innovation

Materials World magazine
1 Dec 2016

To become viable many mining projects need to think differently. Katherine Williams attended Mineral and Mining Processing Europe (MMPE16) to find out what needs to be done.

The European Union faces two main challenges, both of which affect the competitiveness of its industrial base. With Brexit arrangements still to be finalised, London’s miners are worried by the high dependence on imports and the security of raw materials supply.

Sectors depending on access to raw materials, such as construction, chemicals, automotive, aerospace and renewable energy, have a combined added value in excess of €1bln and provide employment for around 30 million people. So has the time come for miners to review what makes a good project?

The premise of MMPE16 was that the development of innovative mining techniques and beneficiation processes is essential to enable the optimal exploitation of the many complex, but rather small scale mineral deposits in Europe. Small being beautiful provided a useful talking point for attendees, with Andrew Fulton of Boulby Potash calling for a return to ‘common sense’, capturing the mood of investors as, ‘I want a return with less risk.’

Fulton used the example of a coalmine where he once worked, which by the 1990s had grown to have around 40 production sections under continuous mining, with a couple of processing plants and roughly 2,000 employees. The mine was seen as a cash cow by management, but production and productivity were beginning to fall and millionaire status was lost. The mine was beyond its half-life and the quality of coal variable. Difficult decisions were taken to restructure the mine infrastructure, allowing better use of energy and improving management control. Output was reduced – helping to cut overall costs while improving output quality. His experiences from this project meant that when looking at Boulby Potash he was ready to look for ‘the best value option’. 

In 2013, Boulby was a potash mine in steady decline and faced the prospect of having to bridge to a new resource. The team at the mine had two options – they could throw more at the mine in terms of people, time and machines or they could take a step back and examine the whole cycle before making a move.

‘It was about controlling our destiny,’ said Fulton. ‘There were difficult decisions but it was about protecting the business going forward. We moved forward as a team, not individuals’. Having decided to follow the latter route, they analysed the reserves and considered available technology and skills to discover how to work with what was left. They developed an understanding of the market to see who they would be dealing with. This 360-degree view helped Boulby formulate a path forward in exploiting the new resource.

Fulton noted that asking the miners how different geology and reserves affected their job provided important information on the actual efficiency of operations. He also sounded a word of caution, ‘It is essential to appreciate how big the gap between expected and historical returns can be.’

Eventually, the move was made to reorganise the mine and focus on polyhalite (a replacement for potassium sulphate in agriculture) – as a result, the footprint of the mine, which had previously grown organically, was greatly reduced. Fulton is optimistic about the future, saying decisions based on tangible information allow the flexibility to act and respond to the markets, noting, ‘If you make a promise, you need to deliver on it.’

Communication is key

Similar themes came from Joe Russell, Engineering Manager of GBM Minerals Engineering Consultants. He asserted that you can’t develop a process flow sheet until you understand what is being processed – a lesson that he illustrated with a Swedish rare earth element (REE) project. His experience, and that of others, indicates a need for all those involved in a mining project to communicate clearly through the whole process. Junior miners need to see more than just the rock they are interested in, banks should be asking whether alternative processes were considered – geologists, mining engineers and those on the face should be discussing the reality of the geology and a clear understanding of waste products should be shared internally and externally. However, Russell noted wryly, ‘Having this conversation never fits into the schedule or budgets.’

Heavy REEs are of huge interest globally and the majority of the supply comes from China, where Russell explained it is not always produced responsibly. In Europe, there are more standards in place, but this means ‘some impacts will be evident and costs tend to be higher. Responsible projects cost more.’

The Swedish project discussed houses zirconium (Zn), niobium, yttrium and Hafnium (Hf) – all strategic metals for Europe – and low in thorium and uranium. This geology affects permits and waste management. Traditionally, this type of project would be an open cast mine. However, in this case, to demonstrate a full understanding of project options the management team evaluated underground mining options and were prepared to accept lower returns to mitigate environmental effects.

REEs have unique flowsheets. The front end is dependent on mineralogy and the back end (purification) is driven both by impurities and the number of end products. Physical beneficiation is used where possible, chemical beneficiation can involve leaching and/or cracking and there can also be purification via chemical separation. The extractive metallurgy must be considered with waste management and the full life-cycle needs to be studied. In the case of the Swedish project HCl, it was initially considered as the acid for the process but this was deemed to be unfeasible because of poor Zn and Hf recovery, as well as the energy costs for recycling and transport of the acid.

Eventually the decision was reached to use H2SO4 – even though it cannot economically be recycled and in Sweden, it was considered unacceptable to discharge solutions containing neutralised H2SO4. As a result, the project makes large quantities of gypsum, affecting the waste profile of the project. A potential solution to harmonise the site mass balance is found by selling nepheline syenite but this means the venture is driven by product quantities versus waste strategies. Russell noted, ‘Waste streams may become more important when planning and pricing projects.’ 

Understanding your reserves

For improved production, understanding the spatial characteristics of mineralogy is important, and Reimar Seltman at the Natural History Museum, UK, is working on a new European minerals database designed to classify deposits as being from good to bad. Using Raman spectroscopy allows the identification of lithium-bearing minerals, which are often under-reported using other methods such as scanning electron microscopy and laser techniques. Seltman explained, ‘Knowing how much energy and money to spend on extraction is vital for returns.’

However, even getting to the point of extraction can be challenging, as Robin Dean of Wardell Armstrong explained. ‘In 2014/15 we saw failing companies – something we had not seen for a long time. Since then, things have moved slightly.’ The firms that weathered the storm have cut costs and made operational savings and Dean noted that profit is still possible, ‘but over a longer period,’ and that it is important to keep an eye on the health of junior miners. ‘If they aren’t doing anything – the industry will fail.’

Once again, the value of communication was emphasised, with the need to consider the downsides of a project as well as the advantages. The owner has to prove it is a good resource for investors, rather than just telling them – the metallurgy, hydrometallurgy and geology all have to be taken into account. ‘We have got to do things to a higher degree to persuade investors that they will gain value’, said Dean. ‘Each bank will have a criteria for investment, make sure you know it.’

Roughly echoing Russell, Dean believes that most money should be spent on the pre-feasibility study stage to provide a ‘comprehensive study of a range of options.’ Then he says the feasibility study is essentially just confirming what is already done. The presentations and discussion showed there needs to be less production for the sake of production, and more communication throughout the value chain. Less is more, except when it isn't.