A breath of fresh air
Landing in the snow-blanketed town of Skellefteå in north-eastern Sweden, it’s impossible to miss the large gold bar in the airport terminal. It’s a reminder that this is the gateway to Sweden’s mining industry.
Just five minutes from the airport, the first reindeer peer curiously through a wire fence on the side of the road. About 50 kilometres away is the town of Boliden, the ancestral home of the Swedish minerals company of the same name, where gold was discovered in 1924.
Old meets new
Just 50 metres from what was once Europe’s largest and richest gold mine is the newest kid on the block: a brand new regrinding station, commissioned in January 2014. The station is used to regrind top hammer bits from Boliden’s four mines in the area, which produce zinc, copper, gold, silver and lead. Regrinding keeps the rock tools in good shape, but the cemented carbide used in the tools contains cobalt, which can pose health risks if it is not contained.
One of the most modern regrinding stations in the world, this joint effort between Boliden and Sandvik* sets a standard for how to protect employees and the environment from cobalt-related activities.
A home away from home
Inside the new regrinding station, massive shiny silver-and-blue ventilation pipes run along the ceiling and walls. Over each grinding machine hangs a large exhaust pipe to extract mist, dust and fumes when the machine is in operation. A good ventilation system is essential to minimize workers’ exposure to cobalt. The machines have splash protection to limit the amount of water mixed with traces of cobalt that falls on the work surfaces. The electrolyte machine, which previously used acid fluid, now uses saltwater.
In the centre of the station is a comfortable break room that can only be entered after passing through a buffer zone, changing clothes and stepping onto a sticky mat to remove all traces of cobalt. It’s clean and modern, a place where the workers can take a hard-earned fika (a Swedish coffee break). They start early, often arriving at Boliden’s mines at 5:30 a.m. to pick up the bits that they will bring back to the workstation.
From clean-up to operation
The need for a new regrinding station arose after Boliden and Sandvik learned that cobalt could be classified as a carcinogenic substance if inhaled. An old warehouse from the 1950s, previously used to house the heating systems, was selected as the site of the new station, and work began in October 2013.
Minimizing exposure to cobalt
• Wear long sleeves, gloves, goggles and face mask.
• Wash hands and face regularly.
• Use a barrier hand cream and a conditioning hand cream.
• Have a good ventilation system in the regrinding station.
• Keep the workplace clean of dust and mist.
• Take care of work clothes to reduce the spread of dust.
To learn more about commitments Sandvik Mining has made to preventing cobalt exposure, visit the company’s Environment, Health and Safety (EHS) campaign site.
Boliden’s Anders Holmbom, the former maintenance manager at the Renström mine, was tasked with setting up the new regrinding station. He says he was happy to see the old station close.
“That place was really worn out,” he says. “Now we have better ventilation, dust control, lighting and more control over the noise. Everything’s better.”
To make it suitable for regrinding activities, a high-tech ventilation system and water pipe system were installed. All the water from the regrinding station, which can contain traces of carbide and cobalt, goes through pipes to a special tank where it is emptied, so none of the water is released into the environment.
Next door is a recycling bin. There, the worn-out bits from the regrinding process are collected to be sent to Sandvik facilities that specialize in recycling cemented carbide.
Holmbom relied on input from Sandvik during the renovation process.
“They fed us figures on how much ventilation was needed for acceptable cobalt limits and how much water and electricity we would use,” he says. “They also gave us suggestions on how to make the site as safe as possible.
“The grinding station sets an example for the standards we want to achieve in meeting cobalt safety requirements.
“It was worth the investment,” he says. “It was a good opportunity to clean up an old house and use it for something new. Also, it was important for us to give the grinders a healthier place to work.”
Safeguarding human health
Minimizing the grinders’ risk of exposure to cobalt was the main driver behind the new regrinding station.
Cemented carbide, which contains cobalt, has been used for machining metal since the 1920s. The powder used in hard-metal products, including rock tools, wear parts and rotary cutters, is a mix of wolfram carbide and cobalt, with sometimes a dash of nickel, tantalum carbide or molybdenum thrown in.
This means that workers at sites where hard-metal products are reground face the risk of exposure. When regrinding, water is used to catch most of the particles, but the operators may still inhale some particles. That means it is essential to have an efficient ventilation system that captures the particles and mist.
The National Toxicology Program in the United States set alarm bells ringing when it found that the risks of exposure were higher than in previous studies, but further research is needed to establish the level of exposure that creates a risk.
Sandvik didn’t need to hear these findings to take action. Its Hard Metal Policy, an industry-first which was implemented in 1999, sets standards for workers in close contact with cobalt.
Sandvik regrinding station at Boliden’s site
The rock tools regrinding station at Boliden in north-eastern Sweden is equipped with one RG470 machine, two RG440 machines, two cross-bit grinders and one electrolyte machine. There are also two other machines that Sandvik “inherited,” which will be replaced when they have reached the end of their life. Sandvik has three full-time employees and one part-time employee working at the station.
The station is used to regrind top hammer bits from the four Boliden mines in the area. In addition, the regrinding staff offer support to the mine staff, transport the bits to and from the mines, select the tools for operations in the mine and test the equipment. Sandvik has offered this service to Boliden since 2001.
Safety comes automatically
Gunnar Nygren has been doing regrinding for the Renström mine for 13 years. He says putting on protective clothing, glasses and earplugs has become automatic for him before he switches on his regrinding machine.
“It goes like clockwork,” he says. “It’s always been important, but the standards are much higher now than when I started out. Besides protective clothing, we’ve also been trained on how to protect our skin – for example, by washing our hands regularly and using a barrier hand cream to keep the skin in good condition and minimize the intake of cobalt through the skin.”
Better quality of life
Even though he now has to drive farther to get to Renström from the new regrinding station, Nygren is not complaining.
“The environment here is so much better for me and my lungs, and that means a better life for me,” he says.
His daughter Jeanette has followed in her father’s footsteps and works as a grinder alongside him. She is equally enthusiastic about the new workplace.
“This place is like a castle compared to the former station,” she says. “It’s much cleaner and more pleasant than the old one. Having a more comfortable workplace makes it much nicer for me to come to work every day.”
Björn Bergmark has to travel the farthest to the mine he is responsible for – Kristineberg, a 240-kilometre round trip. He appreciates having a great work environment to return to.
“This place is another world compared to where we worked before,” he says. “Not only is this station much bigger and more modern, the ventilation system is better. Having clean air at work is really important for me.”
Bergmark is fully aware that working with cobalt is not a normal working environment.
“That’s why it is so important to keep everything nice and clean, to minimize water flow and reduce dust,” he says. “We’ve done a lot of environment, health and safety training about how to protect ourselves and minimize our exposure to cobalt, so I feel well informed on the subject.”
Besides raising internal awareness of the effects of cobalt, Sandvik is also working externally to drive research on the subject. In Sweden, it collaborates with Karolinska Institutet, one of Europe’s most prestigious medical universities, to examine the effects of cobalt exposure through the skin. Together with other hard-metal companies and factories, Sandvik is part of an international study to determine the threat of cobalt to human health, the results of which are due in 2015.
The Swedish government’s exposure limit is 0.02 mg of cobalt per cubic metre of air. Sandvik sets a tighter maximum of 0.01 mg per cubic metre.
“We need to take precautions and put controls in place so our employees don’t face any risk,” says Anna Gruffman, EHS manager for Europe at Sandvik Mining, who is responsible for the global cobalt awareness program.
In addition, annual urine checks and comprehensive medical examinations every three years are mandatory for the employees.
A win-win project
For Mattias Markusson, head of rock tools for Sandvik in Scandinavia, the opening of the new regrinding station is important, not just from an EHS point of view, but also from a customer’s perspective.
“The importance of regrinding is sometimes overlooked,” Markusson says. “When you regrind you extend the life expectancy of the bit, maintain a high product performance and thereby increase the productivity of drilling. In addition, the regrinding station serves as a necessary service and information hub in our collaboration with customers.”
Markusson compares the regrinding station to a service station on a highway.
“It’s about keeping up the flow, keeping things moving and sorting out any problems at an early stage to keep up the drilling performance at the mines,” he says. “Our regrinding people are ambassadors for us. They are problem solvers, a shoulder for the mine staff to lean on when they need advice about how to maintain their drill equipment.”
Holmbom hopes that the pilot at Boliden will inspire others around the world to take a similar approach to improving safety, conditions and performance.
“Safety is No. 1 for us at Boliden, and I hope others will feel inspired to make their sites better places for their employees to work,” he says.
*Boliden built the regrinding station featured in this video, for which Sandvik currently provides all regrinding services of rock tool bits.
History: Boliden was created in 1931 by the merger of Swedish mining companies Västerbottens Gruvaktiebolag and Skellefteå Gruvaktiebolag. From 1940 to the 1960s, Boliden continued to add new mines to its portfolio, including Laisvall, an important supplier of lead in Europe. In the 1960s Boliden branched out into the production of sulphuric acid and chemicals. In the 1970s it expanded into new areas such as lead smelting and overseas operations through a joint venture with the German company Preussag. Sweden’s Trelleborg acquired it in 1987 but sold it nine years later. After being listed in Canada for a short period, Boliden returned to its Swedish roots in 2001 with a listing on the Stockholm Stock Exchange. In 2003 it acquired the smelting and mining activities of Finnish company Outokumpu.
Products: Zinc, copper, lead, gold, silver, aluminium fluoride, sulphur products and nickel sulphate.
Employees: About 4,800 worldwide.
Sites: Boliden operates four mine areas in Sweden and Ireland and five copper, zinc and lead smelters in Sweden, Finland and Norway.