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Aug 03, 2023Walz budget proposal includes millions in grants for taconite industry to reduce mercury, sulfate
DULUTH — Millions in public funding could go toward reducing some of the taconite industry's most stubborn pollutants.
A $20 million request by the Minnesota Pollution Control Agency in Gov. Tim Walz's budget proposal would make $17.6 million in grants available to mining companies to install mercury or sulfate reduction technologies; $2.1 million to ramp up water treatment processes targeting sulfate, phosphate and PFAS developed by the University of Minnesota Duluth's Natural Resources Research Institute; and $300,000 for staffing and running the grant program.
Katrina Kessler, commissioner of the MPCA, told the News Tribune that reducing both mercury emissions and sulfate levels in the taconite industry are key to healthy, safe water.
"Because we have not seen progress like we want to and because of the availability of the surplus, we thought, ‘OK, now's the time.’ We can get some seed money out there to get over that initial capital barrier and see if we can make progress on sulfate and on mercury — both of which combine to be problematic for aquatic life like fish," Kessler said.
As the News Tribune reported in 2021, the taconite industry is not on pace to reduce its mercury emissions by 72% by 2025, a state goal set almost 15 years ago.
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It was part of Minnesota's effort to reduce overall mercury emissions across all industries to just 789 pounds per year by 2025, a 93% reduction in mercury emissions compared to 1995 levels.
Today, the industry remains off pace, putting the state on track to exceed its desired mercury emissions by almost 550 pounds. If the taconite plants follow through on a 72% reduction, the state would still miss the target but only by about 80 pounds.
"Despite significant reductions from some sectors, the MPCA projects that the state will not meet the 2025 statewide reduction goal," the MPCA said in its most recent "The Air We Breathe" report. "Meeting that goal will require significant reduction of mercury emissions from the taconite mining sector and further reductions from mercury use in various products."
According to plans filed in 2018 , the industry has largely said reducing mercury emissions by 72% was either too expensive, not technically possible, or both.
Only Cleveland-Cliffs’ Northshore Mining said it could reach the required 72% reduction, by shutting down its coal-fired power plant and changing working habits on its indurating furnace. Minorca, now owned by Cliffs but then owned by ArcelorMittal, said it could reduce mercury emissions by 22%
The other four plants — U.S. Steel's Minntac in Mountain Iron and Keetac in Keewatin, and Cliffs’ Hibbing Taconite in Hibbing, and United Taconite in Eveleth and Forbes — said reaching 72% reduction in mercury emissions was cost-prohibitive or not technically achievable.
Kessler said the agency knows these are "extremely expensive" upgrades and sees the $17.6 million in matching grants as a possible solution.
The mining companies could choose to use the grant money to reduce either mercury or sulfate — or both.
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"We recognize that the state should not be subsidizing all of it, that there needs to be some skin in the game, similar to how we provide grants to public facilities," Kessler said.
Mercury is found naturally in the Earth's crust, and the amount of it in taconite generally increases from east to west along the Mesabi Range. It's released into the atmosphere through stack emissions as the pellets are fired, or hardened, in the pelletization process, according to a 2003 report from the Department of Natural Resources.
But mercury is a neurotoxin that can harm human health even in small amounts and makes its way back to earth via snow and rain and into water bodies. It becomes toxic as methylmercury and works its way through the food chain.
In 2011, the Minnesota Department of Health found 10% of Minnesota infants born in the Lake Superior basin had mercury levels above the U.S. Environmental Protection Agency's reference dose for methylmercury.
Hassan Bouchareb, an engineer at the MPCA, told the News Tribune that there are three technologies that would work well at reducing mercury: fixed carbon beds, GORE Mercury Control System and activated carbon injection.
All are pricey options.
It costs about $100,000 to remove one pound of mercury using activated carbon injection, with annual operating costs totaling between $5 million and $14 million for each taconite facility, Bouchareb said.
That doesn't include the initial costs of constructing and installing the mercury reduction equipment.
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"There's a lot of zeros attached to these projects," Bouchareb said.
The News Tribune asked U.S. Steel and Cliffs if the companies would take advantage of the grant money if it were to pass. And if it didn't pass, would they still invest in mercury or sulfate reduction without public funding.
"We are unaware of the specifics of the request and have had no discussions with MPCA regarding the proposed grants," U.S. Steel spokesperson Amanda Malkowski said in an email to the News Tribune. "Once details are available, we will review and determine if the program has any applicability to potential future projects at our facilities."
Cliffs did not respond to the News Tribune's request for comment.
The 2025 mercury reduction "goal date is fast approaching," Bouchareb said.
"It's not unattainable, but we certainly need some reductions from taconite as well as additional reductions elsewhere, too," he said.
If passed, the grant program would allow iron ore mining companies to seek funding for a mercury reduction technology or sulfate reduction technology — or both.
Those sulfate treatments could come from the NRRI, which would also receive funding under this proposal to scale up methods it developed to remove sulfate from water, said Executive Director Rolf Weberg.
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Sulfates are discharged into water by industrial activities like mining and wastewater treatment and can harm wild rice at high levels.
In Minnesota, sulfate levels for wild rice waters should be at 10 parts per million.
While reverse osmosis works well in removing sulfates from water, it's often a cost-prohibitive at an industrial scale.
But NRRI's methods could be more cost-effective.
Right now, the treatment plants are confined to trailers — one is a former Minnesota Department of Health trailer, now labeled the Mobile Pilot Unit — which can process about one or two gallons of water per minute.
They’ve been tested at places like Minnesota Power's Boswell Energy Center — a coal-fired power plant — and the city of Aurora's water treatment facility, which is currently releasing treated water of 250 parts per million, 25 times the state's sulfate rule.
One of the methods adds barium chloride to the water, which can separate the sulfate from the water. The method is not new, but the NRRI has invented a way to use it with lower concentrations of sulfate, Weberg said.
The two other options use biological processes, with bacteria eating the sulfate and excreting sulfide, which can then be "trapped" with waste iron, Weberg said.
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Weberg said the different methods could be linked together "in a treatment train," and would ideally rely mostly on gravity to move the water instead of pumps, which add to the expense.
"Let's say we go to a waterbody that has 500 parts per million and we use the biological (method) to knock it down to 200 (parts per million). Then we polish it with a chemical (method), and now we can basically tune a treatment train to give us what we want at the end of the pipe," Weberg said.
Of the $2.1 million requested, $700,000 would go toward scaling up the sulfate technology while $600,000 would go toward phosphate removal treatments and $800,000 would go toward PFAS, or forever chemicals, removal treatments.
Weberg said that scale-up would mean NRRI bringing the trailer-sized experiments all the way up to full-scale engineering drawings that a water treatment plant, mine, power plant or other industrial plants can take and build.
"How do we bring it to the next level so that there's a confidence that we can reduce the risk to investment?" Weberg said. "At the end of the day, NRRI ain't going to build this. That's not our job. Our job is to put it out there and assist other people to adopt."
There's interest. Almost 30 people from private industry joined a March webcast hosted by NRRI, which explained the technologies and future prospects.
But NRRI's potential scale-up hinges on state funding. Weberg said the federal government is unlikely to fund it because getting sulfate to such low levels for wild rice waters is unique to Minnesota.
So if the funding doesn't pass the Legislature?
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"We won't do it. We don't have the money, " Weberg said. "It's that blunt because NRRI is a soft-money organization, and the federal government is not going to pay for this."
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