Coal and coal byproducts produced annually contain enough rare earth elements (REEs) to meet current U.S. demand. The REEs exist in the form of minerals, ion-exchanged elements associated with clays and chemically bonded elements within the organic coal matrix. Researchers at three universities have collaborated to evaluate the effectiveness of existing physical and chemical concentration processes for the recovery of the REEs. The efforts have found that physical separation processes can increase the total REE content in the thickener underflow material collected from a Central Appalachian coal cleaning facility from around 300 ppm to values greater than 17,500 ppm on an ash basis. On the other hand, leaching was effective in recovering REEs from coarse middlings materials collected from multiple coal basins as indicated by recovery values exceeding 80%. Based on material characterization data and process evaluations conducted for several potential feed coal sources, economic recovery of the REEs will require byproduct production of both clean coal and REE concentrate using a process flowsheet that is unique for each source.
|Title of host publication||SME Annual Conference and Expo 2017|
|Subtitle of host publication||Creating Value in a Cyclical Environment|
|Number of pages||7|
|State||Published - 2017|
|Event||SME Annual Conference and Expo 2017: Creating Value in a Cyclical Environment - Denver, United States|
Duration: Feb 19 2017 → Feb 22 2017
|Name||SME Annual Conference and Expo 2017: Creating Value in a Cyclical Environment|
|Conference||SME Annual Conference and Expo 2017: Creating Value in a Cyclical Environment|
|Period||2/19/17 → 2/22/17|
Bibliographical notePublisher Copyright:
Copyright © 2017 by SME.
ASJC Scopus subject areas
- Geotechnical Engineering and Engineering Geology