E&MJ looks at how innovation in energy supply and biodiversity are helping the Swedish powerhouse to futureproof its mining operations
By Carly Leonida, European Editor
Incorporating measures to build resilience in the face of immediate threats such as COVID-19 has been a big focus for many Scandinavian miners this year. However, just as important is the work that these companies are doing to strengthen their businesses and operations against longer term challenges, such as climate change, waste management and social license to operate.
One name synonymous with sustainable mining is Swedish firm, Boliden. The company has a portfolio of metals spanning zinc, copper, nickel, gold and silver among others. This has not only helped to provide stability in the face of fluctuating commodity prices over the past 12 months, but also means it is well positioned to supply European producers of low-carbon energy and transport technologies going forward; a key part of the European Union’s strategy on critical raw metals.
The 2019-2020 financial year was an important one for Boliden. The company invested 8.826 billion SEK (US$971.8 million) in growth and improvement projects; it’s highest number ever. And initiatives to cut energy supply from fossil fuels, minimize waste and rehabilitate mine sites were front and center.
To get a feel for some of these, E&MJ spoke to project managers in two varied yet equally important business areas…
Working Toward Carbon-free Operations
Currently, electricity accounts for 70% of energy consumption at Boliden’s mines and smelters. In April, the company announced it had signed an agreement with Agder Energi for the supply of renewable energy to its operations in Sweden and Finland totaling 1,000 GWh per year for 15 years from 2022.
Jonas Ranggård, manager for Boliden’s Mine Energy Program, said, “We have such clean electricity in Scandinavia, especially in Sweden, that our carbon footprint from electrically powered equipment is now close to zero. The two main sources of CO2 from our Swedish mines are propane for heating incoming ventilation air, and diesel for mining vehicles.
“We have worked intensely over the past few years with ventilation on demand. Boliden was the first company to have full Wi-Fi coverage in all our mines and we use that to position vehicles and control the ventilation systems to achieve maximize efficiency. We have very low ventilation inflow to start with, but now we have replaced some propane burners with electrical heaters and we also have heat exchangers heat the incoming air with the outcoming from the mines.”
While this is a massive step toward achieving Boliden’s goal of a 40% reduction in carbon dioxide intensity (CO2 emissions per unit of metal produced) by 2030, it still leaves the question of what to do about diesel mining equipment?
November 2018 saw the startup of a pilot trolley-assist system with ABB and Caterpillar at the Aitik open-pit mine in Sweden and, following successful operation, Boliden has expanded this investment to its Kevitsa site as well. But there is more to come…
“So far, the Aitik installation has performed very well,” Ranggård told E&MJ. “The original trolley line was built on a waste rock ramp where we could add a third lane. That allowed us to play around with the technology without harming production. We’re now building the first in-pit trolley line that will really push the system capabilities.
“As soon as you start widening ramps in a steep open-pit mine such as Aitik, there are extra waste material handling costs, so we need to be able to fit this technology on a two-lane ramp and that is not that common.
“What we’re doing now is building a 1 km trolley line down into the open-pit mine in very high-production pushback, so we will have high traffic intensity on that line. Then we’ll convert 10 more trucks — equip them with pantographs — and extend or build more trolley lines in Aitik in the next two or three years. We also have funding to build a couple of kilometers of trolley lines in Kevitsa in northern Finland as well and convert 16 trucks.”
The Kevitsa installation was scheduled to be commissioned in the fall of 2020. However, this has been postponed to spring 2021 due to COVID.
Making Trolley Assist Fashionable Again
The Aitik installation sparked renewed interest in trolley-assist technology across the industry, and representatives from various mining companies have visited the site see the system working; the first to operate in Arctic conditions.
“I usually say that we are not the first to build a trolley line, we are just the first to brag about it,” Ranggård said with a chuckle.
“The reason the technology took off in South Africa during the 1980s was due to the apartheid oil embargos. Currently, in Sweden, we have a very similar cost ratio between diesel and electricity as they had in South Africa at that time. Especially since last year when the government took away the tax reduction for mining diesel…
“But we see that this is profitable in Finland as well. And if it’s profitable in Finland, it’s profitable in Canada and South America since they have similar energy prices.”
To cope with the tough environment and the larger mining trucks, the poles and foundations for the trolley lines at Aitik are larger, and the pantographs from the OEM (in this case Caterpillar) are more sophisticated than their 80s predecessors. Otherwise, the systems are fairly similar.
“The long-term target is to have all our trucks running on trolley,” Ranggård explained. “At Kevitsa, we have 16 trucks converted for trolley at present and, in Aitik, we have 14 converted out of a fleet of 40. That is just the start.”
Trolley is Just the Start…
While trolley technology will play a key role in meeting Boliden’s carbon reduction targets, Ranggård said tackling the CO2 footprint of a mine as complex as Aitik requires a multi-pronged strategy.
“Even if we install trolley technology everywhere it’s feasible, we will still only achieve diesel savings of 30%-50%,” he said. “That’s good, but it’s not good enough.
“Sweden aims to be fossil-neutral by 2045, so we need to act thereafter. Pretty much from day one, we concluded that we need to pair trolley technology with some kind of onboard energy storage for our trucks, such as batteries.
“We’ve been putting a lot of R&D into this and have done some simulations together with Chalmers University of Technology in Gothenburg where they simulated the combination of trolley and battery packs on a mining truck. The idea is to take out the diesel engine and fill that space with a really large battery pack.
“You use the battery pack to travel from the shovel up the ramp until you reach the trolley line. The truck then connects to the trolley line, travels up the ramp to the crusher or dump and starts to charge the battery as well. While traveling down into the pit again, the regenerative energy from braking also recharges the battery pack.
“We can definitely achieve the energy balance doing this and also make it profitable. It’s feasible based on the tech-
nology that’s available today, so that’s a top priority for us right now. Trolley is really interesting, but I see it just as a first step toward a completely diesel-free hauling cycle.”
Ranggård hopes to see battery-electric trucks in operation at Boliden’s open-pit mines within the next five years and, thereafter, at other mining operations across the globe.
“We really want others to use this technology as well to help push the costs down,” he said. “We have been sharing a lot of the trolley technology and learnings from Aitik with other mining companies and we will continue doing that for our battery initiatives as well.”
Why batteries? E&MJ asked. Why not use biodiesel or fuel cells to complement the trolley technology?
“Actually, we already have 20% HVO mixed into our diesel. That is partly our own initiative, but it’s also a consequence of the law in Sweden,” Ranggård explained. “There is an option of going all in on biodiesel as well, but you take a huge risk doing so.
“First, it will probably cost more, but it also carries political risk, because a large part of the biodiesel imported into Europe today comes from palm oil or palm oil products.
“When it comes to fuel cells… we would need a really large hydrogen electrolysis production plant on-site. Today, producing hydrogen using electrolysis is only about 70% efficient. Then you have the fuel cells that only have an efficiency of roughly 50%. So, the overall efficiency of using fuel cells is much lower.
“When converting trucks to use hydrogen, you still need a battery pack to store regenerative energy, so we would rather make the battery packs larger and use them with trolley lines instead.
“From other mining companies’ perspectives, I can definitely see why they’re looking into hydrogen, but because we have really good, stable electric supply to our sites, battery plus trolley will be more efficient for us.”
Electrifying the Underground
What about Boliden’s underground operations?
“We already have some electric-driven equipment,” Ranggård said. “We have some electrical pickups and drill rigs, and then we have some upcoming field trials that I can’t speak more about yet. We have been focusing mostly on open-pit mines because they are the largest diesel consumers, but also because mines in North America leading the way on underground electrification, mainly due to legislation and regulations on the working environment.
“We will, of course, try to be early adopters, but we aren’t pushing the OEMs as hard when it comes to underground electrification as we are for the open-pit mining.”
What’s your grand vision for energy efficiency at Boliden’s mines?
“By 2030, I hope that we will have our first underground fossil-neutral mine and that we will have at least a couple of diesel-free large open-pit mining trucks,” he said. “Since the large open-pit trucks have a long lifespan, I don’t think we will be able to replace all of them with battery ones before 2030… but at least some of them.
“And, if we open a new large open-pit mine by 2030, I am convinced that by then, we will have the technology to use diesel-free machinery.”
Growing Interest in Biodiversity
Another important area that will contribute to increased operational resilience is biodiversity. Boliden is currently preparing a guideline to help the company achieve increased biodiversity in all regions where it operates by 2030.
Many of the tools it already uses, such as the mitigation hierarchy to minimize and compensate for potential biodiversity losses, are a key requirement of the International Council on Mining & Metals to which Boliden recently applied for membership.
Anders Forsgren, senior project manager for business development at Boliden, spoke to E&MJ about his team’s work.
“At an international level, we are working through SVEMIN — the Swedish Mining Association,” he said. “The environmental committee has a subgroup focused on biodiversity, and I’m the chairman of that. That group is feeding back to the Convention on Biological Diversity’s (CBD) new framework, which envisages a net positive impact to biodiversity by 2050, and also the European Union’s Biodiversity Strategy — part of the Green Deal — that’s ongoing. We are also currently producing a roadmap on biodiversity financed by STRIM, Boliden and LKAB for the Swedish mining industry as a whole.
“If we go to the next level — Boliden as a company — one of our aims for 2020 is to develop a guideline for biodiversity and land use. That will hopefully be published in October.
“Within Boliden, we have formed what we call the ‘Green Group,’ which drives most of our biodiversity projects. We share information, discuss biodiversity targets, develop benchmarks, share good examples, get inspiration, etc.
“We have meetings four times a year, and the group includes representatives from all our active and closed mine sites, a representative from our smelting business, Boliden’s exploration group, and the group that manages our land and forests.
How do you choose those representatives? Is it based on people’s personal interests or the role that they play at the sites?
“Both, I would say,” replied Forsgren. “We have a lot of people with a biological background, so I would say we have experts in each business unit. It’s really interesting to see the growing concern for this. Even from the management level, there’s a lot of interest in biodiversity, and understanding about its importance, the social benefits, access to land, stakeholders engagement, minimizing of risks…
“Our goal is to contribute to increased biodiversity by 2030, in all regions where we operate.”
Compensation Measures at Aitik
A key project the team has been working on is at the Tara underground zinc mine in Ireland.
“It’s a really good example of a green mine,” Forsgren explained. “If you visit Tara, you will never know that this is quite a big mine site.
“One of the most impressive projects when it comes to offsets or ecological compensation is at Aitik. It’s a really large open-pit mine in quite an industrial area. A few years back, we had to take a new area of land into consideration to expand the tailings facility. It was around 167 ha of forest and the nature was of very high value, so we bought an additional 837 ha of land close to the mine site to compensate for that. We protected it for the future and made it possible for the authorities, county administration to make these nature reserves without cost.
“We moved different types of logs — around 700 just for this research project — different species, different standing dead wood and lying dead wood… We have initiated a research project together with the University of Agricultural Sciences. They are monitoring our progress in moving different species and settling them into the new habitat. We are also funding a Ph.D. project based on this.”
Forsgren explained that collaboration with academia is an important part of Boliden’s work in biodiversity.
“It’s one way to build trust in what we do,” he said. “To me, it’s really important to involve universities and others. There is a big lack of knowledge in this area, and in how we succeed in moving species or creating habitats.
“If we [the mining industry] want to use land and get permits to open new mines or expand, then it’s absolutely crucial that we show we can manage it in a good way.”