Meet Paul Ziemkiewicz, PhD. Paul grew up in western Pennsylvania. As a child, he dreamed of cleaning up his local rivers and streams, which were devoid of life due to acid mine drainage. Today, as the Director of Water Research at West Virginia University (WVU), Paul is living out that dream.
What is acid mine drainage?
Abandoned coal mines cause various types of water pollution. Acid mine drainage is the most prevalent. Abandoned coal mines leave pits of highly acidic water that contain large amounts of heavy minerals. Over time, infiltrated groundwater and surface water from precipitation fill these pits to the brim. When the water spills over, harmful chemicals are carried into the surrounding water and soil. These chemicals can hurt humans, plants, and animals.
How do we clean up acid mine drainage?
Scientists at WVU, with direction from Paul, developed a process for removing the heavy metals from acid mine drainage. This process is used at hundreds of plants across West Virginia and is cleaning up water at the watershed level. With the water cleaned, aquatic life can be restored.
But it gets better…
As scientists were learning more and more about how to turn acid mine drainage into clean water, they discovered that the remaining acid mine drainage sludge was a source of rare earth elements.
17 metallic elements are classified as rare earth elements, and these elements are key materials needed to produce many of today’s high-tech devices – including smart phones. Interestingly, rare earth elements are not actually rare, it is just rare to find them in high concentrations and it is difficult to extract them. This is where the beauty of extracting rare earth elements from acid mine drainage comes in – Paul explains:
“Acid mine drainage happens when coal waste rock weathers and forms sulfuric acid,” Ziemkiewicz says. “The acid leaches all manner of metal pollutants out of rock, so why wouldn’t it leach rare earths? Mother Nature does that heavy lifting for free. Fortunately, AMD is, in fact, enriched in rare earth elements and critical materials in an easily recovered form. Best of all, you can’t recover them without treating AMD to environmental standards. Our byproduct is clean water.”
WVU's Rare Earth Extraction Facility is able to produce very highly-concentrated rare earth products. The image above shows a sample that is 87% rare earth oxide.
With this discovery, WVU was able to approach the US Department of Energy and secure $5M in funding to scale up the Rare Earth Recovery Project. Rockwell Automation also agreed to provide sensor and control technology, and develop a pilot plant for REE extraction, to help push this sustainability initiative forward.
The ribbon cutting for the first rare earth element production facility is just around the corner. Following this, WVU has plans to launch rare earth element production from acid mine drainage across the United States. The work Dr. Paul Ziemkiewicz is doing is changing the face of the energy industry, creating jobs, and cleaning up the environment. At Rockwell Automation, we are so excited to be able to help.
To watch a short video explaining the process, view the story via Rockwell Automation.