Towards more efficient mining: Chalmers University

Published earlier this year, this report profiles the work at Chalmers University in Sweden.

​"At least ten percent of the electricity produced in South Africa is used to crush and grind rock. This statistic is but one metric of the importance of the mining industry to the country's economy. Herein lies the great value of the efforts on the part of two Chalmers students to make the world's largest platinum mines more efficient.

Most people think of gold or diamonds, but in recent years platinum extraction has emerged as the flagship of the South African mining industry. Platinum and a handful of related metals generate the largest export revenues, create the most jobs and make the largest contribution to the national economy.

Today South Africa is responsible for three quarters of global platinum extraction. The country has thereby grown increasingly dependent on the recession-sensitive global automotive industry, as the majority of the metal is used for catalytic converters in automobiles. A town called Mokopane, roughly 300 kilometers north of Johannesburg, is home to the world's largest and most modern platinum mine. Here, the ore is mined in four large open pits and processed in a plant that handles 900 tons per hour. It is here that Magnus Evertsson, professor in Product Development at Chalmers, has made nearly a dozen visits since 2010. And he has seen a plant with major problems:

​“The mine owners are using new, more energy-efficient technology to crush and grind the ore. But the multi-billion dollar facility has only been able to run at 60 percent of its planned capacity.”

Chalmers researchers have paired up with the University of Cape Town in an effort to improve the process.

"Comprehending the plant has presented a major challenge. But now we have a better understanding."

Magnus Evertsson has drawn the conclusion that the problem stems not from the new technology itself, but rather the staff's ability to monitor and control the complex processes of crushing and grinding. Could there be lessons to be drawn from the auto industry?

"I was influenced by the ideas of Lean Production - the Toyota-inspired method of streamlined manufacturing. There are methods for measuring equipment effectiveness that might apply here as well,” he says.

This ‘half-baked thought’ soon emerged as a suitable idea for a thesis project. So it was that Magnus recruited Anton Kullh and Josefine Älmegran from the Quality and Operations Management Masters Program to spend the 2012 autumn term in South Africa. During their joint degree project, they created a ‘management tool’ to help production management understand how the crushing process works and what is required to improve it.

"In a continuous flow of several hundred tons an hour, the usual way of measuring quality will not work," explains Anton Kullh when I meet both of them a few weeks after his return to Gothenburg. The entire endeavor worked out so well that Anglo American, one of the world's largest mining companies, is now considering introducing this methodology at its other South African plants as well -- and perhaps even in other countries.

"It's very encouraging to receive confirmation that we actually accomplished something," says Josefine Älmegran.

"According to the company, this was the first time that students have done something that could be directly applied to production."

Their first impression of the facility was one of "incalculable magnitude." A seeming maze of conveyor belts that move between different ore crushers and mills in an area totaling over one square kilometer. Also impossible to calculate is the amount of data product management can obtain from the advanced production process data system. Everything from weight and flows to temperature, particle size and the power consumption of the numerous process steps are measured and recorded -- the number of data points is close to 400,000!

"But what do all the numbers mean and what values are of interest? These were some of the questions that we were trying to answer," says Josefine Älmegran.

By identifying a number of key figures, they were able to create a management tool which now provides production management with real-time information about how the crushing process is progressing. Both students describe the cooperation with the company's technical staff as totally unpretentious. The company is already using some of the key figures they highlighted in its strategy to increase efficiency. The management tool as a whole will be evaluated in the spring. And, of course, Josefine Älmegran and Anton Kullh hope that once the tool has completed the development stage, it will gradually go on to find full-scale application.

Their stay in the country coincided with the worst labor dispute in the South African mining industry since the fall of Apartheid -- a conflict which incidentally had platinum mining at its epicenter. Tens of thousands of workers went on wildcat strikes for higher wages and mining companies responded with mass dismissals. Over 40 people died in violent clashes between demonstrators and police.

The facility at Mokopane, however, was not involved -- the strikes were concentrated at mines performing underground work. But the labor dispute and the massive staff cuts that several mining companies have since announced still represent a signal that the essential mining industry is facing major changes.

Magnus Evertsson points out that mining companies in South Africa have traditionally played an important role as a creator of jobs -- hardly any work has been seen as so unimportant as to not lead to a job.

Now he believes that as mechanization and automation progress, the mining companies will move towards a more western model: higher wages, but fewer jobs. For Chalmers, the research project in South Africa presents a glimpse into a "new" area for the university: the international mining industry. Although Magnus Evertsson himself spent twenty years researching the most effective way to crush stone, his focus has been on the construction industry's need for gravel and macadam.

"Mining is very energy-and resource-intensive. The world's need for minerals is increasing at a steady pace, while the mineral content of the ore mined is constantly declining," he explains.

"In other words, in order to obtain a given amount of metal, ever more mountains must be pulverized. Therefore this is a direction of research that is well worth our while."


THE SUPERVISOR ON SITE during Josefine Älmegrans and Anton Kullhs thesis work was Aubrey Mainza, who leads a research group in mineral processing at the University of Cape Town. He recently visited Sweden and Chalmers for the first time:

​"As new and more advanced technologies are introduced into the mining industry in South Africa, the primary motivation is not to rationalize and reduce the number of employees. Rather, it is to produce more within the context of existing limitations - primarily the availability of energy but also of water," he says. Aubrey Mainza also points out that research and better technology can increase the yield of the ore being mined.

"Today, waste from mining still contains valuable minerals."

But technological progress also affects the workplace.

"Technology creates jobs that are safer, as is seen in the increasing degree of mechanization of underground mining. Furthermore, technology requires employees with better education, which in turn means higher wages. Advanced equipment requires more maintenance, and this provides more jobs. This will help the mining industry to create wealth."

Although he believes that the mining industry in South Africa has a bright future, he also has concerns.

"We do not know if the number of employees in the mining industry can be maintained at the same level as in the past when more advanced technology is introduced. In our case many miners will need to be retrained for other jobs. Here, mining companies have a huge responsibility," says Aubrey Mainza.​

By: Björn Forsman"