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Unearthing mining trends

 

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An in-depth look at the mining industry reveals that multi-disciplinary cooperation is crucial for its future development.

In the early 1970s there was much debate about whether there were sufficient mineral resources to meet anticipated demand. After all, mineral resources are non-renewable and ultimately finite. But they are also a moving target, and difficult if not impossible to quantify.
    It is difficult to estimate the amount of coal and minerals that can be economically mined. This is because their deposits, or occurrences, vary in composition even within limited distances. Also, to minimise costs, mine operators often only precisely measure the reserves in the part of the mine to be exploited in the medium term, rather than the total reserves available. So, even mined ore occurrences are not fully quantified. Finally, we don’t tend to search for minerals until we need them, so many occurrences probably remain undiscovered. Discoveries are still made of major ore bodies.
    There is also a qualitative complication. What is currently defined as an economically mineable resource may be deemed uneconomic if someone discovers new resources that are cheaper to mine or if the mineral in question is substituted by another material. Likewise, if demand for a mineral-based product grows as a result of new technology, then it will become more economic to mine more of the source mineral.
    What the 1970s debate did establish was that there were more than enough minerals available, therefore silencing the issue of geological availability.

Too many eggs in one basket
At the same time, the oil crisis emphasised that the accessibility of resources was an important issue. This made the oil industry spend large amounts on developing resources in politically safe areas. These exercises underlined one fact: Just because there were technically mineable resources did not mean that they were available.
    There was also a widespread belief in developing countries that a significant proportion of the revenues from any exploitation of their mineral resources should stay in the country. These countries then implemented fiscal and other regulations to this effect, which proved a major disincentive to international mining companies and their financial backers.
    But political changes, brought about by economic failures, have helped change such accessibility problems. The breakdown of the socialist economic system in eastern Europe and central Asia, and its modification in China, has opened up these areas to international exploration and mining companies. This redirection has also been encouraged by the increasing complexity of the mining permit procedures put in place by developed countries, in response to public demand for environmental protection.

Embattled mining
The global mining industry is often an unpopular one. This is partially a result of the nature of the mining process: It is destructive in nature and, especially in the case of surface mining, can temporarily disrupt the natural environment on a large scale. While it is possible to prevent the latter by mining deposits sequentially in small sections, this action prevents the economies of scale that keep operating costs low.
    It should also be noted that the mining industry itself has contributed to its unpopularity. For the past 40 years, some mining companies have opposed or tried to delay the implementation of policies intended to minimise adverse environmental impacts of mining. They often say that such policies would put them at a competitive disadvantage with operations in countries where such controls did not exist.
    This sort of response won mining few friends but it did buy time to develop more economic technical solutions to environmental problems. At the same time, the industry has found ways to cope with higher labour costs in developed countries. Indeed, high labour costs have been a major spur for developing more efficient and safer mining techniques and equipment. There have been some notable exceptions to negativity. In Japan, for example, the government has financially assisted the metals industry to meet new emissions standards. In Scandinavia, a regulatory framework has been developed in which the community, operator and regulator work together to decide land-use planning issues.
    Meanwhile, multidisciplinary partnerships have made considerable strides in making efficient use of more productive equipment and techniques. And some mining companies have recognised that real financial benefits can be gained from more environmentally friendly mining and mineral processing. This surely is the way forward. To build sufficient mines in the future, mining companies must not only make themselves more cost-efficient, but also more easily acceptable as neighbours. Financial incentives can help them do this.

Increased productivity
Prime examples of more productive equipment in surface mining are large loading shovels with bucket capacities of 45 cubic metres and more, which are matched to off-highway dump trucks that can haul more than 300 tonnes at a time. These trucks are the products of collaborations between tyre manufacturers, diesel engine specialists, electric motor developers, truck designers and mine operators.
    Underground mining equipment productivity in hard rock is also improved by developing larger machines, such as load-haul-dump vehicles with bucket capacities of 25 cubic metres, which can be used in bulk mining operations. Another mining efficiency involves improving the precision of the blasthole drilling process through better drill bit and steel designs and more instrumentation. Softer rock and underground coal mining operations now use highly productive mechanical equipment for excavation. The advantage here is that the equipment can work continuously, whereas drill-and-blast systems must usually stop work during blasting.
    A key focus for collaborative teams in the underground sector is automation of the mining equipment system, which can not only improve productivity by responding more quickly and working more continuously, but also improve safety since the operator is removed from the working face. Mines already making some use of automated drilling include the LKAB iron ore mines in Sweden, Inco nickel operations in Canada and the brand new Northparkes copper-gold mine in Australia.
    However, optimising mining operations is not simply a matter of bringing in more productive equipment. Careful management is necessary to get the best value from today’s exceedingly expensive large units. Studies comparing the performance of longwall mining systems in different coalmines have backed this up, for example. In open pits it doesn’t matter if you have the world’s largest shovel if you can’t keep it supplied with the correct sized trucks so it can work flat out. Likewise, a solid maintenance system is essential to keep the equipment running.
    Both these aspects – good management and good maintenance – of machine operation have also benefited from multidisciplinary technical collaborations. Such collaborations have included the development of rugged sensors for measuring machine loads and condition, together with communication systems and data processing systems to transmit and make this information available to the control staff and the equipment operator. Most recently, the use of satellite technology has been employed not only for checking locations of individual trucks, but also to position drilling equipment exactly where it is required.

Ghost-town blues
It is a fact of mining life that good deposits must come to an end. While the remnants of historic mining towns make fascinating tourist attractions, we tend to forget the social upheaval and grief among communities affected by mine closures. The European coal industry, hit by the joint impact of cheaper coal production elsewhere and fuel substitution by its traditional customers, is a case in point. One of the recent major changes in mine planning has been the requirement to plan for closure in terms of facilities and environmental impact. Perhaps it should be a requirement to plan for the socioeconomic fallout as well.

Kyran Casteel  
senior consulting editor at World Mining Equipment

 

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