Tuesday, March 15, 2011

Taking a risk for rare earths

8 March 2011

KUANTAN, Malaysia - A colossal construction project here could help determine whether the world can break China’s chokehold on the strategic metals crucial to products as diverse as Apple’s iPhone, Toyota’s Prius and Boeing’s smart bombs.

As many as 2,500 construction workers will soon be racing to finish the world’s largest refinery for so-called rare earth metals - the first rare earth ore processing plant to be built outside China in nearly three decades.

Rare earths, a group of 17 elements, are not radioactive themselves. But virtually every rare earth ore deposit around the world contains, in varying concentrations, a slightly radioactive element called thorium.

Once little known outside chemistry circles, rare earth metals have become increasingly vital to high-tech manufacturing. But as Malaysia learned the hard way a few decades ago, refining rare earth ore usually leaves thousands of tons of low-level radioactive waste behind.

The word ‘low’ here is just a matter of perception - it’s a carcinogen,” said Dr. Jayabalan A. Thambyappa, a general practitioner physician and toxicologist. He has treated leukemia victims whose illnesses he and others have attributed to the old Mitsubishi Chemical refinery.

That plant, on the other side of the Malay peninsula, closed in 1992 after years of sometimes violent demonstrations by citizens protesting its polluting effects. Now, in an engineering effort that has largely escaped the outside world’s notice, Mitsubishi is engaged in a $100 million cleanup.

Currently, a giant Australian mining company, Lynas, is hurrying to finish a $230 million rare earth refinery here, on the northern outskirts of Malaysia’s industrial port of Kuantan. The plant will refine slightly radioactive ore from the Mount Weld mine deep in the Australian desert, 2,500 miles away. The ore will be trucked to the Australian port of Fremantle and transported by container ship from there.
The new Lynas refinery, with nearly two dozen interconnected buildings and 50 acres of floor space, will house the latest in pollution control equipment and radiation sensors. A signature feature will be 12 acres of interim storage pools that will be lined with dense plastic and sit atop nearly impermeable clay, to hold the slightly radioactive by-products until they can be carted away.
But carted to where? That is still an open question.
Building the lined storage pools was one of the promises Lynas had made to win permission to put the refinery here, in an area already environmentally damaged by the chemical plants that line the narrow, muddy Balok River.
Mr. Curtis, the Lynas chairman, insists that the new factory will be much cleaner and far safer than the old Mitsubishi plant, which “never should have been built,” he said recently.
One big difference, he said, is that the ore being imported from Australia is much less radioactive. It will have only 3 to 5 percent of the thorium per ton found in the tin mine tailings that Mitsubishi had processed. And he said the Lynas factory would also process 10 times as much ore with only twice as many employees - about 450 in all - thanks to automation that will keep workers away from potentially harmful materials.

But the long-term storage of the Lynas plant’s radioactive thorium waste is still unresolved.

Source: The New York Times

No comments: