What’s Going on Here?
From hard drives and electric vehicles, to wind turbines and generators, a plethora of modern technologies rely on the incredible magnetic properties of rare earth elements like neodymium. This large demand has led to the establishment of a sizable global neodymium material flow. The life cycle of neodymium can be analyzed throughout its collection, processing, manufacturing, transportation, use, and eventual disposal to better understand the effects that neodymium as a material has on society, energy, and the environment. Due to uncertainty in metric choice, unavailability of data, and the large scale and distribution of neodymium extraction, it is difficult to come to any exact figures. However, through the use of data where it is available and estimation where it is not, we can come to reasonable conclusions regarding the effects of the global flow of neodymium.
How Much Do We Use?
Since Neodymium is so useful in the electronics and energy industries, the scale of its usage is quite large. The Materials Information System of the European Commission concluded that global collection of rare earth elements yielded 130,000 tonnes of metal in 2012. Since neodymium is not the only rare earth element currently extracted and used by humanity, neodymium extraction comprised only 21,000 tonnes, or 16%, of that figure. While this data only applies to global collection in 2012, the organization also estimated that neodymium demand would grow at a rate of 7% each year. Using this estimate, we can calculate approximate neodymium extraction figures for 2017, 2020, and 2050:
Accounting for significant figures, these calculations yield estimates of approximately 30,000, 36,000, and 270,000 tonnes for the years of 2017, 2020, and 2050, respectively. It is important to note, however, that these figures are only meaningfully accurate if two important assumptions hold true:
- Global demand of neodymium continues to grow at a rate of 7% each year.
- Global extraction of neodymium is able to keep up with the rate of demand.
Where Do We Get It?
Approximately 95% of global neodymium extraction occurs in China. The next biggest players in neodymium collection are Australia and the United States. Notable reserves have also been identified in South Africa, Canada, and North Korea. While the former two may become global contenders in the near future, the political implications surrounding North Korean trade make it unlikely that the country will soon enter the market.
Why Does Supply Matter?
The importance of the location of the world’s neodymium supply can be understood in the context of the following example:
“Between 2010 and 2012 the Chinese government put strict export quotas on their rare earth minerals … The quotas reduced the output by nearly 60% compared to the 2008 total release of 34,156 tonnes. These quotas created a gap between demand and supply and large increases in the prices of the rare earths.” (Haque et al)
After global concerns were raised by bodies such as the United States, the European Union, Canada, and Japan, China eventually agreed to revert its restrictions. While the prices of rare earth elements such as neodymium eventually dropped back down, the dramatic surge in market price resulting from China’s actions shows just how much influence the country has on the global supply of neodymium.
Since neodymium is very abundant in the earth’s core, most experts believe that current reserves will not limit neodymium production in the foreseeable future. However, the actual extraction and processing of neodymium may not be able to keep up with the exponential growth in global demand. If demand surpasses the ability of countries to provide neodymium, another sharp increase in the price of neodymium, such as the one seen between 2010 and 2012, may occur. Such a price surge would likely decrease the viability of several types of technologies which rely on neodymium, including many clean-energy solutions.
Where Does It Go?
Neodymium is collected via the mining of monazite and bastnäsite ores, usually in open pit mines. The process of producing usable neodymium involves removing the unwanted earth (overburden), mining the ores, crushing and grinding, separation, extraction, concentration, and final processing. According to research conducted by Australia’s Commonwealth Scientific and Industrial Research Organization in 2014, the separation stage alone ends up requiring around 0.6 GJ of energy and 1 ML of water per tonne of rare earth ore produced. During the extraction and concentration stages, additional resources are required. Specifically, the rare earth ores are treated with concentrated sulfuric acid, hydrochloric acid, and ammonium bicarbonate. Unsurprisingly, this stage of the production is also energy intensive. The ores are roasted in 400 – 500 degrees Celsius temperatures, washed, and heated again. Finally, neodymium and other lighter metals are extracted via a process called molten salt electrolysis. Additionally, neodymium must also be shaped, magnetized, coated, and transported to the factories where it will be used in the making of various products. Transport is especially difficult, due to neodymium’s incredible magnetic properties. Since neodymium magnets are so powerful, careful precautions must be taken. As a result, shipping a neodymium magnet disc with a diameter of just 6 inches requires packaging it in almost 8 cubic feet of cardboard, Styrofoam, and plywood. It is difficult to estimate the intensive energy demands of heating, treating, magnetizing, and shipping neodymium. However, it is safe to say that the .6 GJ / tonne required for the separation stage of neodymium mining is only a minuscule fraction of the total energy required to manufacture industry-ready neodymium magnets.
How Is It Used?
After neodymium is extracted from the mined rare earth ores and shaped into convenient forms for shipping, it enters the consumer and industry space. Some neodymium enters the market in its pure form, to be used in dielectrics, glass coloring, catalysts, welding goggles, CRT displays, various alloys, rubber additives, capacitors, and lasers. However, the vast majority of the material is combined with iron and boron to create Nd2Fe14B permanent magnets. While permanent neodymium magnets are often cited as being necessary for the manufacturing of electric vehicles, they are also used to make starter motors, brake systems, seat adjusters, and car stereo speakers. In the electronics industry, neodymium magnets are used in speaker systems, headphones, vibration motors in smartphones, and most importantly, computer hard drives. However, the use of neodymium in wind turbines and electric vehicles is frequently stressed due to the immense amount of material required. The Institute for Energy Research and the Bulletin of Atomic Sciences estimate that a 2 megawatt wind turbine requires 800 pounds of neodymium. By contrast, Toyota’s Prius is estimated to use around 2 pounds of neodymium, but around 2 million units have been manufactured and sold.
Where Does It End Up?
The end-of-life destination of neodymium is particularly important for two reasons: neodymium which is recycled can help satisfy the global demand for the material and neodymium which is disposed of has environmental impacts. Unfortunately, current recycling rates for rare earth elements like neodymium are abysmal. For example, it is estimated that in 2013, only 1% of cell phones were recycled. Even worse, consumer headphones, earbuds, and hard drives are likely recycled at much lower rates. In 2014, Australia’s Commonwealth Scientific and Industrial Research Organization estimated that neodymium reuse, recovery, and recycling manages to meet only 1% of the global demand for the material. The large majority of the metal, then, is disposed of in landfills or other dumps. Consumer electronics containing neodymium are shipped from countries which use them in massive quantities to the slums of Hong Kong, Ghana, and India. Thankfully, however, neodymium carries nowhere near the health concerns of dangerous metals like mercury, lead, arsenic, and cadmium. However, the global flow of neodymium is not without its own health concerns. The waste water from the mining and separation of neodymium ore, when improperly disposed, accumulates into large and dangerous “tailing ponds”. Baotou, China, one of the world’s largest suppliers of neodymium and other rare earth metals, is home to perhaps the most famous example of such a “pond”. The toxic lake of Baotou, filled with black sludge as far as the eye can see, is the result of flooding the town’s farmland with the harmful byproducts of rare earth metal mining. Since tailing ponds are created by neodymium production, they are not direct results of neodymium disposal. However, since around 99% of neodymium is disposed of, rather than being recycled, mining sites like Baotou are met with immense pressure from global demand.
What Does the Future Hold?
Finding an alternative to the use of neodymium for permanent magnets would help ease some of the world’s demand for the material. Such a reality is certainly not impossible. In fact, even engineers at Toyota have been researching ways to create electric cars without the use of rare earth metals. Likewise, discovering more energy efficient processes for extracting, treating, and magnetizing the metal would help reduce its energy demand. However, the biggest challenge facing the global material flow of neodymium is its poor recycling rate. Unfortunately, this is the area which has seen the least global attention. While researchers are looking into neodymium substitutes and better ways to harvest the metal, very little awareness has been raised about the benefits of recycling the material. While the world’s reserves of neodymium are vast, current extraction methods are energy intensive, often environmentally dangerous (as in the case of Baotou), controlled by certain countries (mainly China), and could potentially become economically unviable (as seen in the 2010-2012 price surge). If society wishes to continue using wind turbines, electric vehicles, hard drives, and speakers, it is going to need to do more than just find better ways to produce magnets and cars. Namely, policy makers and citizens of technologically developed countries must begin to raise awareness of the importance of recycling the luxury goods we have come to appreciate.
Materials Information System. “Neodymium.” European Commission SETIS. Apr 2016. https://setis.ec.europa.eu/mis/material/neodymium
Haque, Hughes, Lim, and Vernon. “Rare Earth Elements: Overview of Mining, Mineralogy, Uses, Sustainability and Environmental Impact.” Resources. MDPI. 2014.