Mechanised mining's exponential growth dispels the myths that new techniques are not proving profitable on the African continent. In the last decade production volumes of these mines rose from 2-million tonnes in the year 2000 to 35-million tonnes just ten years later. Based on current mine development plans it is projected to increase further to 80 million tonnes per year by 2020 representing significant growth in the future.

Following one or two highly publicised incidents where technology failed to deliver comparable yields to manual operations on certain shafts, dissidents have begun proclaiming the failure of mechanisation in the sector altogether. When examining the facts however, nothing can be further from the truth. Five of the eight major underground platinum mines in the region that are profitable are mechanised, including Zimplats, Mimosa, Mototolo, Bathopele and Two Rivers.

“To claim that mechanisation cannot work in narrow platinum mines is not true. Risks are inherent in both processes, but merely following a one-size-fits-all approach is more dangerous. Even despite the difficulty of extracting platinum in the narrow confines of platinum mines we believe human hands do not always have to carry out the “dirty work” in order to be profitable,” says Rod Pickering for Sandvik Mining.

Tougher conditions
Having worked on a broad cross-section of mines - mechanised and “traditional” - he believes that the answer to mining profitably is to do what is correct on the particular mine and individual shaft. In future, with price pressures mounting, he says skilful mining will be required to extract the maximum efficiency out of each ton of ore mined. As ore bodies tail deeper into the depths of the earth, so do mining operations become more difficult and dangerous thereby forcing mine operators to adopt smarter approaches.  

“To uphold the argument that mechanisation has failed is to concede platinum mining in the country is unsustainable. We are already beginning to push the boundaries of human endurance underground in our platinum mines. Rock drill operator’s lives are not easy underground and the nature of the work is arduous and difficult. A rock drill weighs 23kg and the thrust leg weighs 10kg. This is connected to a pneumatic hose and a water hose and has to be man handled into place and operated by a single person. As a result operators are commanding far higher salaries which will in turn threaten the future sustainability of some traditionally operated mines. 

“The challenge to prove the efficiency of mechanised mining is to begin using different measures to underpin the success or failure of mines or operations within a mine. A good example when measuring productivity of manually operated mines over mechanised mines has been the use of formulas relating to the cost per tonne of ore removed from the mine. Modern mine managers, however, prefer measuring the cost per ounce extracted, as precision mechanised mining techniques are able to exclude unnecessary rock in favour of mining only rich deposits of ore.

Cost per ounce
Much has been said about the operating cost comparison between the different techniques. Narrow reefs are typically less than one metre in width, which means that mechanised room and pillar mines are about 1,8m in height compared to conventional mines. With a tramming width of about 1,3m it is not practical to consider costs on Rand per tonne basis, but rather on a Rand per ounce of PGM material extracted. Based on a study by JP Morgan, mechanised mines are lower cost operations when measured in R/oz of PGM than conventional mines.

Capital deployment
Capital costs, by comparison, can be divided between the cost to establish the mine and get it up to full production and the more direct capital cost of the equipment used to mechanise the mining operations. Mechanised mines are easier and quicker to start generating revenue.  All development is on reef and pays for itself compared to footwall development in conventional mines that is a cost with no return.  In start up mining operations the time to start revenue generation and build up to name plate tonnage has a direct impact on project NPV. The capital cost of the equipment is about 20 - 25% of the life time cost of the equipment and its operation. In other words the operating cost and utilisation efficiency swamp the capital cost.

Fit-for-purpose
“In terms of risks, modern measures are more succinct and clearly examine all aspects of a mine’s operation, including health and safety. For example, are injuries or lost lives tolerable and is the risk of incurring a Section 54 mine closure due to unsafe practices conceivable. In time, putting lives at risk will push salaries up and this in turn will put undue cost pressure on mines and seriously compromise long-term sustainability,” adds Bjorn Gohre, general manager, marketing and sales at Sandvik Mining.

Yet overseas mines, with comparable conditions, have overcome similar challenges by introducing mechanisation into some or all of the processes in their mines. Based on the premise that one glove does not fit all, South African platinum miners will need to find smart solutions on an individual basis - for each mine at each shaft. Examples like Lonmin’s Saffy shaft which famously de-mechanised in favour of manual labour and now struggle to keep their ore reserves open due to low manual development rates belie the success of the neighbouring Hossy shaft which has fully mechanised development and keeps their ore reserves open due to higher development rates.

Sandvik Mining vice-president hard rock cutting Arne Lewis says the company reaffirms its strong commitment to mechanisation in order to rebuild the country’s competitiveness on a global scale. “Worldwide, Sandvik makes a significant investment in research and development and that is something it maintains even during tough economic climates. If you can mechanise, you can remove a person from an area that has certain dangers and put him in a much safer working environment. There is often productivity enhancement with automated or remote controlled operations which ultimately leads to an overall cost advantage, making operations safer, more productive and ultimately more sustainable.”

“The inability of some South African operations to mechanise successfully is often blamed on operator skill and literacy levels, yet our studies highlight the problem being a lack of skill and reluctance to change at supervisory level through to the senior ranks within mining operations”, says Andre O Smit, operational manager Sandvik trans4mine. “Our training and awareness programmes are now targeting these levels with great success and we are eager to see those results materialising throughout our customer base in the next few years.”

In many ways South Africa is blessed with the best of both worlds where we still have high numbers of technically-skilled labour to undertake difficult mining operations where machines can’t. We also have companies like Sandvik Mining that brings world-leading machinery and mechanisation to our mines. The question remains now, whether South African platinum miners will have the conviction and skill to embrace change in order to raise production to levels obtained overseas in mines that no longer use traditional drill, blast, excavate methods.