Adams stated:
"I do not think that anything that we do will "solve the problem of nuclear waste" since it is not really a problem in the first place.
There are plenty of people in the world with an interest in making it an unsolvable problem; those people will never be satisfied no matter how tightly we wind up the technical details.
My solution is to accept the fact that there is opposition and to try to help the rest of the people understand that the opposition is a body of people with financial interests in slowing nuclear power. That way, the opposition does not disappear, but they become far less effective in changing the way that we need to do business."
My response:
One major advantages of having an up to 98% burn up rate plus FP recycling is that very little of site construction has to be devoted to post reactor by product storage. The facilities to handle LWR post reactor fuel, are not inconsiderable part of current reactor construction expenses. The fluoride salts FP extraction technology researched and developed at ORNL during the 1950's to 1970's demonstrate that low cost extraction of FPs from nuclear fuel is possible. By separating FPs we change them from "waste" into by products, which have real and/or potential uses in the economy.
I am in complete agreement with the very idea that there is no such a thing as "nuclear waste" in the conventional meaning of the term. Where I differ with Rod is in our evaluation of a once through fuel cycle, which I regard as very inefficient and "wasteful" because it fails to extract more than a small fraction of the potential energy from nuclear fuel. I do see a waste of fuel potential by the once through Uranium fuel cycle.
I discussed the fundamental problem of the uranium fuel cycle in a March post on Nuclear Green. My discussion of the relative merits of the uranium fuel and thorium cycles, rests on the discussion of those cycles in WASH-1097 which makes the issues wonderfully clear.
"The relevant characteristics of the important fissile and fertile isotopes in thermal and fast-spectrum reactors are summarized as follows:
(1) Thermal absorption in U-233 produces more neutrons per neutron absorbed** than does
corresponding absorption in either Pu-239 or U-235.
(2) The neutron production for U-233 is relatively insensitive to change in temperature, but for U-235 and Pu-239 eta decreases as the temperature increases. Thus, the advantage of U-233 over U-235 and Pu-239 is more pronounced in a hard (higher energy) thermal spectrum than in a soft (lower energy) thermal spectrum.
(3) From a nuclear standpoint, the use of U-233 in a thermal reactor makes it possible to achieve
higher fuel conversion ratios and longer fuel burnups than is practical with either U-235 or Pu-239 (Section 2.2).
(4) The higher conversion ratios which can be obtained in thermal-spectrum reactors when using U-233 instead of Pu-239 can result in a significantly better utilization of natural uranium fuel resources with thorium-fueled reactors than with the low-enrichment, light-water cooled uranium-fueled reactors (Section 2.3).
(5) A higher breeding ratio can be obtained with Pu-239 than with U-233 in a very high-energy, fast-neutron spectrum reactor. On the other hand, in a degraded (10 to 100 keV) fast spectrum, U-233 would probably be as good as, or better than, Pu-239. Also, the variation of U-233 and Pu-239 cross sections with energy are such that improved reactivity coefficients would be obtained with the use of U-233 in a large sodium-cooled FBR. This leads to improved nuclear safety characteristics.
(6) The energy dependence of the fast-fission cross sections of Th-232 and U-238 is such that the use of Th-232 would produce an improved reactivity coefficient in a liquid-metal-cooled FBR. The fast fission cross-section of Th-232 is much lower than that of U-238 so that use of the latter leads to much larger conversion ratios in fast-spectrum reactors."
The inference is clear, even in fast neutron spectrum reactors, the Thorium fuel cycle is more efficient and thus less wasteful than the Uranium fuel cycle. My disagreement with Rod is not about these facts, but about their implications for reactor and especially PBR construction costs. If i am right, the prize for lowest overall reactor construction should be given to the reactor that uses fuel most efficiently, all other things being equal. There is little doubt that if the price of fuel reprocessing is factored into the price of reactor construction the LFTR would be lss expensive than the PBR. If you do not pay the price of reprocessing, cost are related to the cost of storing and handling of unprocessed post reactor fuel.
My other disagreement with Rod has to do with the best approach to dealing with opposition to nuclear power. I believe that the problems of post reactor nuclear fuel, and the problems of reactor safety are real issues that the nuclear community needs to solve. The best answer to opponents questions about "nuclear safety," and "nuclear waste," is not simply a public education, being able to say, "our reactors are safe and do no produce nuclear waste," is really what, in my view, is required to answer nuclear critics.
I must add that I have very high regard for Rod's intelligence, integrity and abilities. Rod isan amazingly talented man, and I am very happy that we have him in our camp.
I must add that I have very high regard for Rod's intelligence, integrity and abilities. Rod isan amazingly talented man, and I am very happy that we have him in our camp.
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