Thursday, 10 January 2013

China Blazes Trail for 'Clean' Nuclear Power from Thorium


Princeling Jiang Mianheng, son of former leader Jiang Zemin, is spearheading a project for China's National Academy of Sciences with a start-up budget of $350m.

He has already recruited 140 PhD scientists, working full-time on thorium power at the Shanghai Institute of Nuclear and Applied Physics. He will have 750 staff by 2015.

The aim is to break free of the archaic pressurized-water reactors fueled by uranium -- originally designed for US submarines in the 1950s -- opting instead for new generation of thorium reactors that produce far less toxic waste and cannot blow their top like Fukushima.
----------------------------------------------
Thorium has its flaws. The metallurgy is complex. It is "fertile" but not fissile, and has to be converted in Uranium 233. Claims by the International Atomic Energy Institute in 2005 that it has "intrinsic resistance" to proliferation but have since been qualified. It could be used as feedstock for bombs, though not easily.

Yet it leaves far less toxic residue. Most of the mineral is used up in the fission process, while uranium reactors use up just 0.7pc. It can even burn up existing stockpiles of plutonium and hazardous waste.

Cambridge scientists published a tantalising study in the Annals of Nuclear Energy in February showing that it is possible to "achieve near complete transuranic waste incineration" by throwing the old residue into the reactor with thorium.

In other words, it can help clean up the mess left by a half a century of nuclear weapons and uranium reactors, instead of transporting it at great cost to be encased in concrete and buried for milennia. It is why some `greens' such as Baroness Worthington -- a former Friends of the Earth activist -- are embracing thorium. Though there are other reasons.

The thorium molten salt process takes place at atmospheric pressures. It does not require the vast domes of conventional reactors, so costly, and such an eyesore.

You could build pint-size plants largely below ground, less obtrusive than a shopping mall, powering a small town the size of Tunbridge Wells or Colchester. There would be shorter transmission lines, less leakage, and less risk of black-outs. The elegance is irresistible.

Mr Sorensen says his group Flibe Energy is exploring 250 MW reactors that could be tailor-made to power a single steel plant. Imagine the benefits for China, which drives is collosal steel industry -- 40pc of the world's total -- with high-polluting coking coal, much of it shipped from distant mines in lorries.

Mr Sorensen said his molten salt design could not cause a meltdown because it never reaches a high enough temperature to melt the nickel-alloy vessel.

If there is an emergency, a plug melts and the salts drain into a pan. "The reactor saves itself," he said.
http://www.telegraph.co.uk/finance/comment/ambroseevans_pritchard/9784044/China-blazes-trail-for-clean-nuclear-power-from-thorium.html


[Posted at the SpookyWeather blog, January 10th, 2013.]

No comments: