August 5th, 2009 | 4:19 pm

Inquisitive Questions on Recycling

by Gilles Clement, Vice-President of Recycling Technologies, and Dr. Alan Hanson, Executive Vice President of Technology and Used-Fuel Management

Today we’d like to highlight a thought-provoking question about recycling that was asked recently on the AREVA North America blog.

Randal Leavitt asked:

Recycling fission fuel is better than not recycling, but there are other approaches that are better still. My preferred technology is the liquid fluoride thorium reactor. How do we shift the nuclear industry over to this technology?

We definitely agree that recycling used fuel is much better than “throwing it away” (i.e: direct disposal). The ability to shift the nuclear industry to a new technology is really something that is determined by the success of three conditions:
1. It must be proven and demonstrated at large industrial scale
2. It must be economically justified as compared to other alternatives
3. It must be licensed by the appropriate nuclear regulatory authorities

Large scale deployment of new technology requires – as soon as the principles are reasonably well stabilized and enough data from R&D is available – the preparation of a thorough and credible business case to justify the large investments needed to develop it.

To demonstrate that a new technology is fully proven and obtain the final license, one has to go through a lengthy piloting process. This involves designing, building and operating a series of “pilot models” of progressively increasing scale. A first model is developed to evaluate and understand the basic performance of the new technology, and it takes several years to test it rigorously. This first step is followed by incremental increases in the scale and the capacity of the models, (generally two further steps) to reach full commercial production size. The final model is considered as pre-industrial and is used to demonstrate the full range of safety, security and reliability requirements. Today nuclear reactors fueled with thorium have not yet been shown to meet the three conditions.

  • Max Epstein

    I’d like to repeat a question I originally posted in the blog post after Randal Leavitt’s question above.

    I have heard the argument (including by at least one professor with a related PhD) that the benefits of reprocessing in terms of reducing volume of waste overstate the real benefits, because the reprocessed fuel comes out hotter (or ends up hotter after being run back through a reactor). Since the real constraint on storage capacity of any geologic site is heat load, not volume of the casks, then the heat issue would be a problem if true. But obviously many experts do not seem to agree with this, which I presume means they do not agree that reprocessing and reusing fuel leads the eventual waste to be hotter. If you could help clear this up it would be much appreciated. Thanks.