Despite their name, rare earth metals are are abundant in nature but are hazardous and costly to extract. Rare earth metals are a group of 17 metals that have moved from being a by- product of mining operations to an important component of many or most of the hi-tech products that are becoming/ have already become a key component of everyday life for most of us. As a society nearly all the technology that we use includes rare earth metals, including many of the green technologies (tablets, cell phones, solar panels, wind turbines, electric cars) that we hope will help us transition to a more sustainable society. This makes rare earth metals both a valuable input into, and a strategic for, sustainable economic development. This is especially true within the context of climate change, environmental degradation and an ever increasing need for more efficient resource use. It is therefore essential that these metals are used and extracted in the most sustainable way possible.
It is particularly important to consider rare earth metals within the renewable energy and green technology context. It is also essential to weigh up the pros and cons of transitioning to new technologies before simply adopting them. It is just as important for your ecocide that you know what the real impact of your renewable energy, paperless office, electric car etc really is as you do not want to be lulled in to a false sense of green-ness. For example:
- Electric cars seen as a way to reduce carbon footprints and GHG emissions so necessary for climate change mitigation. However, an electric car might use nearly 10 times the amount of rare earth metals as opposed to a conventional car which uses a little more than one pound of rare earth materials.
- A single large wind turbine (rated at about 3.5 megawatts) typically contains 600 kilograms, or about 1,300 pounds, of rare earth metals. (http://dgrnewsservice.org/2012/04/09/bright-green-technologies-dependent-on-rare-earth-metals-that-may-soon-be-economically-unviable/)
- Moving towards a paperless office may save trees and water but the technology needed to do so will require rare earth metals that will necessarily involve mining, pollution and environmental degradation.
I am not saying new hi-tech solutions are unsustainable, what we need are solutions that have the least impact. It is therefore essential that we weigh up the costs and benefits of any new, greener technologies that we adopt as we make our way towards sustainability.
|Rare Earth Element||Used in|
|Scandium||metal alloys for the aerospace industry|
|Yttrium||phosphors, ceramics, metal alloys|
|Lanthanum||batteries, catalysts for petroleum refining|
|Cerium||catalysts, polishing, metal alloys|
|Praseodymium||improved magnet corrosion resistance, pigment|
|Neodymium||high power magnets for laptops, lasers|
|Promethium||beta radiation source|
|Samarium||high temperature magnets, reactor control rods|
|Europium||liquid crystal displays, fluorescent lighting|
|Gadolinium||magnetic resonance imaging contrast agent|
|Terbium||phosphors for lighting and display|
|Dysprosium||high power magnets, lasers|
|Holmium||the highest power magnets known|
|Erbium||lasers, glass colorant|
|Thulium||ceramic magnetic materials under development|
|Ytterbium||fibre optic technology, solar panels|
|Sources: (Nath, 2011) (British Geological Survey, Royal Society of Chemistry, 2010)|
At present the majority of the rare earth metals are mined and processed in China. China produces an estimated 97% of the rare earth metals that are used around the world (Nath, 2011). China is also associated with unsustainable mining and production practices making society’s reliance on unsustainably sourced Chinese rare earth metals somewhat “unsustainable”.
An example is;The town of Baotou, in Inner Mongolia, where two-thirds of Chinas rare earths are mined and processed. Baotou is the largest Chinese source of rare earth minerals, the minerals are mined at Bayan Obo, north of Baotou then brought to Baotou for processing. The mining and processing operations in Baotu has resulted in soil, air and groundwater pollution which has in turn negatively impacted on the health and well-being of people living in the area.
“According to an article published by the Chinese Society of Rare Earths, “Every ton of rare earth produced generates approximately 8.5 kilograms (18.7 lbs) of fluorine and 13 kilograms (28.7 lbs) of dust; and using concentrated sulfuric acid high temperature calcination techniques to produce approximately one ton of calcined rare earth ore generates 9,600 to 12,000 cubic meters (339,021 to 423,776 cubic feet) of waste gas containing dust concentrate, hydrofluoric acid, sulfur dioxide, and sulfuric acid, approximately 75 cubic meters (2,649 cubic feet) of acidic wastewater plus about one ton of radioactive waste residue (containing water).” Furthermore, according to statistics conducted within Baotou, “all the rare earth enterprises in the Baotou region produce approximately ten million tons of all varieties of wastewater every year” and most of that waste water is “discharged without being effectively treated, which not only contaminates potable water for daily living, but also contaminates the surrounding water environment and irrigated farmlands.” (www.thecuttingedgenews.com, 2012 )
While rare earth minerals may be able to help us transition to a more sustainable society they are not the silver bullet to enabling the transition towards a low carbon, greener economy. It is therefore essential that mining and processing of the rare earths occurs in a sustainable manner as does the use of technologies containing rare earths. As a society we need to be more mindfull of how we use our technology and not blindly assume that we are doing the environment a favour by changing to a so called “greener technology”.
So the next time a new tablet, ipod, cellphone or whatever is released don’t just buy the new one for the sake of having the latest model, “Wasting rare earth minerals on gadgets is not going to get us any closer to being sustainable”, (says the blogger typing away on her latest hi-tech tablet/ gadget!)
Dr Chandrika Nath 2011, Rare Earth Posst Note UK Parliament.
Rare Earth Elements, June 2010, British Geological Survey