Rare but everywhere
From iPhones and TV to wind turbines and electric cars, rare earths are minerals essential to modern technology and 21st century society. Brigid Mullane spoke with experts on Australia’s nascent rare earth industry, its place in the international market and the environmental implications of mining.
Out in Western Australia, an ancient volcano is stirring: it is called Mount Weld, and it’s near Laverton, about 700 kilometres northeast of Perth.
While it’s not actually going to erupt, with some help from heavy machinery, it will be releasing tonnes of minerals called rare earth elements, that are essential to modern life.
Dr Matthew James of Lynas Corporation Ltd, the mine’s developer, said he was enthusiastic about the many applications of these minerals, particularly in computers.
“That hard disk drive has two rare earth magnets, one to make the disk spin, the other that controls the arm that reads and writes data on that disk and that has allowed the miniaturisation of these hard disk drives . . . the phosphors behind the computer screen – the materials that create the colour and light – are a combination of rare earths.”
“Europium creates the colour red and terbium creates the colour green and there are no substitutes for those, so no rare earths – black and white world,” he said.
Rare earths in minute quantities are found in many of our modern electronic gadgets, but their crucial role today is in green energy technology, notably, hybrid electric cars.
“Rare earths create the world’s strongest magnets – neodymium rare earth magnets – and they’re used in the electrical generator of the car, also the electric motor of the hybrid vehicle,” James said.
A car like the Prius needs about one kilogram of neodymium for its generator and motor as well as 10 to 15 kilograms of lanthanum for its battery and one-kilowatt wind turbine’s generator requires more than 200 kilograms of neodymium.
So, in the renewable energy age, the market for rare earths will continue to expand, and Australia may be looking at a new mining boom.
In the mining boom, China will be a competitor, not a customer.
In recent years, China has virtually cornered the rare earths market, with an estimated 60% of the world’s reserves and 95% of production.
China wants to use its supply for its own technology industries, and has recently reduced exports – that could mean higher prices in the short term.
On the other hand, China could increase production and exports at any time and with cheap labour, poor environmental regulation and a large black market, it could price other suppliers out of the market, as it did in the late 1990′s.
Despite the uncertainty, Australian miners are forging ahead with exploration and development.
The Mount Weld site is likely to be the first to get its minerals processed to a factory-ready state, by the second half of 2011.
The processing starts at the concentration plant adjacent to the mine, where the ore is crushed and ground to liberate the fine grains of rare earths.
These are added to a soap-like solution where they cling to the bubbles and float to the surface, where the floatation process
produces a concentrate of various rare earths.
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The concentrate is then shipped to the company’s processing plant at Kuantan on the east coast of Malaysia.
“Our plant uses quite a lot of water, natural gas and chemical reagents, and water in Western Australia is scarce; in Malaysia it’s plentiful. Also the chemical reagents we require we can find locally in the industrial estate in Malaysia”, James said, adding that natural gas is also available nearby from Petronas, Malaysia’s national oil and gas company.
At Kuantan, the concentrate gets severe treatment.
“We hit it with sulphuric acid at relatively high temperatures and this breaks down the minerals and releases the rare earths from the mineral structure,” says James.
The resulting sulphate solution is subjected to a technique called solvent extraction, to separate the individual rare earths and produce single oxides such as neodymium oxide, ready for industrial use.
The company expects to sell its output to manufacturers in Japan, Europe and the United States, with many supply contracts already signed.
One question remains: Will the environmental benefits of green technology be undermined by the environmental impact of mining and processing essential components like rare earths?
James believes that his company is dealing with the issue.
At the Australian mine site they retain the topsoil removed from the pit area to allow future rehabilitation.
The plant in Malaysia needs more complex procedures.
“We have a very good . . . waste gas system that cleans the gases before they’re released to the atmosphere. We have what will be the largest industrial wastewater plant on the east coast of Malaysia, again to ensure that any water we release is properly treated and cleaned and meets the environmental standards,” he said.
The company also makes use of the plant’s byproducts.
“The non-rare-earth solids that we produce are actually synthetic mineral products like gypsum . . . and these products can be used in cement products or plasterboard.”
Recycling is another goal of the industry.
James noted that it is difficult to recycle the very small quantities in many discarded electronic items, but recycling programs are being put in place in the automotive industry.
As well, magnet manufacturers make use of production off cuts, and so optimise resource use.
So, if Australian rare earth producers cannot compete with the Chinese on price, they may be able to trade on their environmental credentials, at least until China catches up.
And with Australia’s new government contemplating a revised mining tax and a carbon-pricing mechanism, this new mining boom could be a long one.
Brigid Mullane is a reporter for Diffusion. She is also a minor shareholder in Lynas Corporation Ltd.