Enormous cache of rare earth elements hidden inside coal ash waste, study suggests

[Jim__]

From phys.org

Total and potentially accessible coal ash reported by the electric power sector during 1985–2021. Credit: Reedy et al
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Even though the level of rare earth elements in coal ash is relatively low when compared with those mined from geological deposits, the fact that the ash is readily available in large quantities makes it an attractive resource, said co-author Davin Bagdonas, a research scientist at the University of Wyoming.

"There's huge volumes of this stuff all over the country," Bagdonas said. "And the upfront process of extracting the (mineral host) is already taken care of for us."

The researchers found that about 70% of the coal ash produced from 1985 to 2021—a total of about 1,873 million tons—is potentially recoverable, with the material stored in landfills, ponds and offsite storage areas. The rest of the coal ash has been sold and used by other industries, such as cement production and road construction.

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For example, ashes from Appalachian Basin coal contain the highest amounts of rare earth elements, with an average value of 431 milligrams per kilogram. But only 30% of the rare earth elements it contains can be extracted. In contrast, coal from the Powder River Basin has the lowest average value of rare earth elements at 264 milligrams per kilogram, but it has an extractability of about 70%.

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[OKIsItJustMe]

1. It also should be an incentive to clean up the mess

There may be concerns about the other stuff found in the “ash” but just leaving it there isn’t good either.

https://www.epa.gov/coalash/coal-ash-basics

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Why does EPA regulate coal ash?

Coal ash contains contaminants like mercury, cadmium and arsenic. Without proper management, these contaminants can pollute waterways, ground water, drinking water, and the air.

The need for federal action to help ensure protective coal ash disposal was highlighted by large spills near Kingston, TN and Eden, NC which caused widespread environmental and economic damage to nearby waterways and properties.

• Kingston, Tennessee.
• Eden, North Carolina.

To address the risks from improper disposal and discharge of coal ash, EPA has established national rules for coal ash disposal and is strengthening existing controls on water discharges. For more information, visit the following webpages.

• Regulations for the safe disposal of coal ash.
• Water regulations on power plant discharges.

Last updated on April 18, 2024

Personally, I would like to see them go after the “tailings pile” in Mineville, NY. (It also represents a great deal of rare earth material, just sitting in an artificial hill.)

https://www.usgs.gov/news/national-news-release/mine-waste-eastern-adirondacks-may-be-untapped-accessible-source-rare

Mine Waste in the Eastern Adirondacks May be Untapped, Accessible Source of Rare Earth Element Minerals
By Communications and Publishing December 22, 2020

Waste rock from long-closed mines in the eastern Adirondack Mountains, New York, may prove valuable due to its rare earth element content, according to newly published research. The results are from airborne and ground surveys conducted by the U.S. Geological Survey and collaborators.

Rare earth elements are critical for advanced technologies such as cell phones, supermagnets, computers, medical apparatus, renewable energies and advanced defense systems. Currently, the U.S. depends heavily on imports for rare earth mineral resources.

“The possibility of accessing rare earth elements from mine waste and mill tailings is attractive partly because the minerals have already been excavated from the ground,” said USGS scientist Ryan Taylor, who led analyses of rock samples from the region. “This would reduce mining costs by making it easier to access the minerals. It also allows ‘recycling’ of discarded materials, which could help to remediate these mined areas,” he said.

USGS scientists were able to detect both mineral deposits and larger mill tailings piles from airplane surveys of old iron mines that occurred in December 2015. They then analyzed samples that showed rare earth content from the deposits, waste and mill tailings.

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