Re: CO2 emissions/atmospheric increase -C-14 Dose reduction

[AndrewsJP@AOL.COM]

Here is more about C-14 related to nuclear systems.  The highly touted pebble bed reactors now proposed will use graphite coated and carbide coated fuel pellets. Some carbon-14 is formed in these.  Any recovery operations involving burning the graphite and carbide coatings to retrieve and recycle uranium-233 (from thorium) and -235 and plutonium-238 and -239 will presumably release radioactive carbon dioxide to the atmosphere.  This will probably be deemed unacceptable because of the increase in long lived atmospheric carbon-14, so some capture may well be required.  One of the early proposals for the HTGR system was to capture the carbon as carbonate such as calcium carbonate which is generally very insoluble (clamshell, limestone, etc.). I have been away from the HTGR systems for so long that I am not up to date on current spent fuel handling thoughts.


Also, large-scale processes that produce such materials as an agricultural byproduct would also tend to reduce the carbon dioxide load in the atmosphere.


Of course, we could just bury pebble bed spent fuel in Yucca Mt. and be done with it.  It won't go anywhere. Ever. (Unless we need to retreive it in 150 years to reprocess it to get the materials for fueling the breeders that will be required then.)


Just some thoughts.


John Andrews

Knoxville, Tennessee