‘Consuming plutonium for producing energy is the superior option'

A paper published today (May 10) in Nature states that the process of converting plutonium to MOX (mixed oxide fuel containing uranium and reprocessed plutonium) for use in reactors is costly and risky. Using in fast breeder reactors does not address the central issue of reducing the quantum of separated plutonium. So should India be taking this route?

Dr. Anil Kakodkar, former chairman of the Atomic Energy Commission, explained to R. Prasad, in an email,why India should continue with the fast breeder route for disposing of the man-made element.

 

The authors argue that direct plutonium disposal is a “less costly and less risky method” compared with recycling plutonium and using it in reactors? Your comments.

 

In a world where direct permanent disposal of even spent nuclear fuel has remained an unresolved issue for several decades with no sign of its resolution in sight and an estimated used uranium fuel inventory that has piled up to a level in excess of 270,000 tons as per WNA [World Nuclear Association] estimate, above argument is questionable. 

Clearly direct permanent plutonium disposal is a more complex matter as compared to disposal of spent nuclear fuel. On the other hand, there is today commercial scale experience in France where nearly entire spent fuel arising is recycled as MOX fuel in PWRs [pressurized water reactor]. In India, we have adopted the policy of recycling right from the beginning.

They state that recycling plutonium is “dangerous.” Your comments

 

“Direct permanent plutonium disposal” is a greater long term danger since one is creating a potential “plutonium mine” which can be open to uncontrolled access after a long time when most of radioactivity would have decayed out.

On the other hand, it is a superior option to consume plutonium in a controlled manner for producing much needed energy and permanently dispose of only proliferation irrelevant radioactive materials. There is sustained and successful commercial experience on reprocessing and plutonium recycling in France. In India too, we have significant and successful industrial scale experience on reprocessing and plutonium recycling. 

Is it right that both kinds of disposal — direct disposal after immobilizing plutonium, and disposing MOX spent fuel — “require about the same repository space”? 

 

May be. However in the latter case one would have extracted much larger energy and plutonium rendered more proliferation resistant. Thus repository space needed per unit of energy produced would be much less. It is worth noting that even MOX spent fuel has been reprocessed on a trial basis. 

Will we not end up with more plutonium by converting plutonium to MOX fuel and using in fast breeder reactors? Will we not reach a stage when the amount of plutonium produced is more than what we can use?

 

The safest place for storing plutonium is in operating nuclear reactors. Reprocessing can be always be adjusted to just meet the demand. For a country like India where our per capita electricity use is 15-20 times lower compared with industrialised countries, this question is irrelevant.

While the use of thorium will not result in plutonium, will the U233 that is produced be more difficult to handle (since U233 is a gamma radiator unlike plutonium)?

 

Surely U233 is more difficult to handle if one resorts to technology similar to what one uses in the case of plutonium. That is where we need to adopt technologies appropriate to handling U233. By the same token U233 use is much more proliferation resistant. We also need to recognize that when used with thorium, destruction of fissile plutonium is much deeper. 

The authors have quoted a year 2000 estimate that recycling plutonium through the MOX route adds about $750 million every year in the case of France? That will mean that power produced by France by recycling plutonium has become expensive. Will that be the same case in India too? 

 

As I understand it, in France, cost of MOX and uranium fuel on per unit energy basis is similar. Even if you take the above number to be true, this corresponds to less than 9 paisa per unit. I think this is not too much recognizing the fact that this avoids a potential plutonium mine. In India, the experience is that we practise high technology at a much lower cost. 

They have also cited the example of the U.S. where the cost of recycling through the MOX route has increased from $4 billion in 1999 to $13 billion now. Your comments.

 

I cannot comment on this since escalation in cost is related to issues of project management. 

-The Hindu