The recent dramatic financial turnaround of Anglo American Platinum (Amplats) is due in part to a revolutionary mine mechanisation programme that commenced several years ago. Gold and platinum mines are at the forefront of this revolution. Every aspect of mining is being questioned, researched and subjected to technological improvement.
“If we do nothing, we have possibly 10 years in which we lose another 200 000 mining jobs,” says Sietse Van Der Woude, senior executive for modernisation and safety at the Minerals Council of SA. “This is not an option. Each of these employees support between seven and 10 dependants, so the effect of losing these jobs would be catastrophic for the country.”
At the SA-Russia Platinum Group Metals (PGM) conference in Johannesburg this week, mineral resources minister Gwede Mantashe spoke about the need for more exploration to breathe life back into mining. Russian technology, he added, would benefit PGMs, both in driving demand for PGMs and in using innovation in minerals extraction and processing.
Though mine mechanisation threatens the replacement of people with machines, government and other stakeholders recognise that something must be done to rescue a dying sector. Government has pumped R150 million over three years into mine modernisation research and technology development. For every R2 contributed by government, the Minerals Council is contributing another R1 over and above its own R&D spend.
Mechanisation does not automatically mean job losses. There may be some loss of less skilled jobs, but there’s a greater need for higher skilled workers to run the automated machines and artificial intelligence that will define the mine of the near future. Mechanisation allows mines to remove humans from danger by sending machines to drill, blast and clear ore in far narrower spaces than is currently the case, and at much lower cost. It allows mining to enter areas currently considered too hazardous for humans, and to operate 24/7. Suddenly, ultra-deep mining is not so daunting. With 24/7 mechanisation, SA could expand its gold output by nearly a quarter and return the country to its once exalted status as one of the world’s leading producers of gold.
A position paper by the Minerals Council of SA, entitled People-Centred Modernisation in Mining, says mechanised drilling and blasting could extend the life of a low-grade mine with a four-year life expectancy to 15 years – and by as much as 25 years with full mechanisation and 24/7 operations.
“Rolled out across the industry, modernisation could unlock the potential of an equivalent 11 large gold mines and eight platinum mines,” says the position paper. “In this way, modernisation not only preserves existing jobs, but also creates new jobs, so contributing safely and profitably to the economic development of the communities surrounding mining operations and society at large.”
Amplats’s Mogalakwena open pit mine in Limpopo has improved ore tonnage by more than a third since 2012 using state-of-the-art rope shovel technology (a bucket-equipped machine used for digging and extracting ore). The mine now plans another 31% improvement to match and then exceed the world benchmark.
Mine mechanisation is a concept that has been around for the better part of a century, when power drills first replaced the pick and shovel around 1910. Steam-powered trains were used even earlier than this to remove ore from the stope face to the shaft. This technology is still widely in use, though the locomotives of today are powered by diesel and fuel-cell batteries. Mechanisation gained wider appeal after the miners’ strike of 1987, when the industry employed more than 500 000 workers. Today, the figure is about 110 000.
A trove of technologies is currently in use or in testing, though mechanisation involves more than efficient machinery: Kumba Iron Ore’s Sishen mine in the Northern Cape has improved its fleet productivity by 62% since 2016 by redesigning the mine, using better blasting efficiencies, reducing the size of the fleet and by motivating and rewarding the workforce.
Kumba CEO Themba Mkhwanazi says the group’s vehicle collision avoidance system is a world leader, while advance process control systems using state-of-the-art technologies to optimise output and yields has resulted in a 6% improvement in productivity. “Reducing costs and improving safety and productivity are key to our technological improvements,” says Mkhwanazi. Future innovations involve ‘smart mining’, where mining will be undertaken more selectively and with minimal impact on the environment.
Smart mining is a phrase often heard in the industry, and involves a range of technologies, from automated drilling to advanced process controls, geo-spatial planning, 3D underground mapping systems and the integration of thousands of mine functions into a single, real-time data centre. Most of this technology is already available, but applying it across the board has proven difficult.
Sibanye-Stillwater’s Burnstone mine tested a remote-controlled drilling machine to access dangerous and previously inaccessible areas. The machine functions at low operating heights, with higher yields and lower costs.
Anglo American has partnered with Croatian vehicle manufacturer Dok-Ing to develop a low-profile dozer, no higher than an adult’s knee, to operate in confined spaces of between 1.2 and 1.6 metres. It can scale 30 degree gradients, making it excellent for stoping work, and is capable of clearing up to 120 tonnes of ore an hour.
Amplats is at the forefront of this modernisation revolution, which involves more than the use of machines. It’s referred to as the fourth industrial revolution, where people, materials and machines are monitored in real time. This is not in wide use just yet, but nor is it science fiction. One mine that is leading this new industrial revolution is Dundee Precious Metals. It provides wireless communications underground, allowing small battery-powered Wi-Fi tags to track people, assets and equipment. The system is also of huge benefit in tracking personnel in the event of an underground accident.
Explosives have become safer, and, with mechanisation, can be inserted into holes using remote-controlled machines. But blasting could soon become a thing of the past, as new non-explosive drilling technologies gain wider acceptance. Underground blasting and roof collapses remain an ever-present threat for those working underground. JSE-listed Master Drilling has developed a new drilling machine that requires no blasting, and delivers faster access to ore bodies than existing technologies. Remote-controlled roof bolters are another feature of modern mining, providing stronger roof support for those working underground.
Amplats is testing equipment for hard rock mechanised mines to operate with low profile mining technology. In its 2016 annual report, the company says: “Our aim is for 80% mechanised production from the repositioned portfolio. The move to mechanisation will ensure these alternative mining methods will be safer and more productive, therefore more cost-effective for the business.”
Says Van Der Woude: “The holy grail of mining is to remove humans from danger and to access ores that are otherwise inaccessible through the use of machines, and to be able to monitor in real time all aspects of mining – human, material and machines. We are not there yet, but we are close.”
Amplats’s half year results announced this week show unit costs down 3%, PGM production up 4%, and Ebitda up a whopping 70% to R6.8 billion. This is in part due to its extensive modernisation programme.
In 2015, Africa’s first 100 kW fuel cell that runs on platinum and natural gas was installed at the Minerals Council of SA’s head office in Johannesburg. The use of fuel cells as a power source underground rather than diesel reduces the need for ventilation and hence cuts back on power consumption.
Among the gold mines, mine mechanisation has a potted history. Narrow ore bodies do not always lend themselves to machine mining, and more than 500 million tons of ore is locked up in pillars that were left behind to prevent roof collapses. Gold Fields’ South Deep mine is a world leader in mine mechanisation and one of the few to have made a success of it, but that’s a story for another day.
Watch: Mechanisation at work … Kumba Iron Ore introduced driver operator assist technology at its Sishen mine in 2016. In the half year to June 2018 total fleet productivity was up 17% over the same period in 2017, allowing Sishen to park 11 trucks and achieve a 7% improvement in truck utilisation without negatively affecting production.