Rare Earth Mining and Its Damaging Impact
An open pit rare earth mine (click to enlarge) |
The
mining of rare earth elements (also known as REEs) is different from many other strategic materials
because of the unique geology of rare earths. Rather than being highly
concentrated in ore deposits, most rare earth elements are found in combination with many
minerals in very small amounts. This scattered nature of rare earth deposits
means that although there are more rare earths than copper or zinc in the
Earth's crust, they are far harder to extract in an economically feasible
manner. Exploitable deposits of rare earths are often found inside uncommon
types of igneous rocks, like alkalines and carbonatites. Rare earth elements are also present
in alluvial deposits, and alongside highly valuable iron-oxide copper-gold
deposits. As assaying these scattered mineral deposits of REEs is costly, much
exploration is still being done for suitable REE mines. Most current production
of rare earth elements is within China, where it is mined from carbonates and
phosphates. (To read more about this, click here.)
After
rare earth-containing minerals are extracted from the ground, they must be
refined, separating the rare earth elements from impurities. Because of their
low concentration, vast quantities of ore must be extracting, resulting in much
of the refining process being performed on site, at the mine. Refining REEs
involves chemically treating the ores, with many REEs requiring different
chemical techniques for each kind of ore. Typically, REEs are refined by
milling the ore, down to fine particles, where it will then be subjected to a
series of specific chemical treatments.
The complex nature of refining these ores,
along with the massive amount of ore that must be processed, means that there
is a large amount of chemical waste and
tailings, some of them radioactive, produced by rare earth mines. (For more information on the waste produced, and its damage to environment, read here and here.)
An
interesting look into the process of how rare earth elements are produced and the
issues currently present in rare earth extraction, are shown in this video of
the Bayan Obo Mining District in Baotau, China, which produces nearly
half of the supply of all rare earth metals.
An illegal mountaintop-removal REE mine in China (click to enlarge) |
Even
more damaging than facilities like Bayan Obo are the illegal mines that have
sprung up throughout China as small companies bribe officials and quickly
pillage an area, extracting REE without any regulation or regard for the
environment.
To stop the terrible toll that REE mining is
taking on people and the environment in the emerging third world, it is
important that we act now to increase the supply of rare earths through
recycling, and lessen the demand of rare earths through intelligent
consumption (like skipping upgrade cycles and buying refurbished phones).
If we could raise the current rate of E-cycling from 25% to 50% we would
recycle another 2.37 million tons of electronics annually. I urge everyone
to act now by contacting all their friends and family members and
offering to help and urging them to recycle all of their E-waste.
Sources:
Electronics Waste Management In the United States Through 2009. (2011, May 1). Retrieved November 20, 2014, from http://www.epa.gov/waste/conserve/materials/ecycling/docs/summarybaselinereport2011.pdf
Rare Earth Elements. (n.d.). Retrieved November 20, 2014, from http://web.mit.edu/12.000/www/m2016/finalwebsite/elements/ree.html
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