March 05, 2009
Nuclear Reactor Could Operate 200 Years On Same Fuel
Imagine a reactor that can burn very abundant Uranium-238 and not need refueling for a couple of centuries.
The scientists there have come up with a preliminary design for a reactor that requires only a small amount of enriched fuel--that is, the kind whose atoms can easily be split in a chain reaction. It's called a traveling-wave reactor. And while government researchers intermittently bring out new reactor designs, the traveling-wave reactor is noteworthy for having come from something that barely exists in the nuclear industry: a privately funded research company.
As it runs, the core in a traveling-wave reactor gradually converts nonfissile material into the fuel it needs. Nuclear reactors based on such designs "theoretically could run for a couple of hundred years" without refueling, says John Gilleland, manager of nuclear programs at Intellectual Ventures.
Since refueling is a rare event waste generation is far less and therefore waste disposal becomes a much smaller problem. Also, the U238 would cost less and the way it burns in this design greatly reduces the risk of nuclear proliferation. What's not to like?
Also read about the Aim High Plan for Factory Mass Produced Liquid Flouride Reactors. They burn thorium which also is more abundant than Uranium-235 which current reactors burn.
Darn; this screws up our plan to remain energy dependent. The Chosen One will not be happy. Brothers and sisters; comrades fellow members of the bourgeois we much oppose this with vigor. Remember attack the messenger not the message. It's so hard to recall all these socialist terms. Thought we were through with all that. The O brings it all back with a venegence.
Let us be frank and earnest about the process that "converts nonfissile material into the fuel it needs". It's making either U235 or Pu239 and not just a little bit either. The Soviets had a similar design...they moderated it with carbon graphite, cooled with with water from a nearby lake, and watched it all go up in a plume of radioactive smoke one night. Fast breeder, using U238 to make Pu239, no containment and damned little control of the safety process (with a notable absence of what could be termed adult supervision, but hey, that's socialism for you).
Also, given current technology, or even expected technologies in metallurgy, why would you suppose that the loaded fuel is the limiting factor in reactor designs? It isn't. Its the vessel, specifically the welds that connect the various forgings of the vessel together, that over time and accumulated exposure to fast neutron flux, will embrittle and or crack to the point where it is no longer sound as a pressure vessel. WHen that happens (actually, before that happens), the reactor installation has come to the end of its operating life.
If now you have a vessel that has no further commercial value, and that is full of a century or more of spent fuel (that would be a Sh@t load, by the way, measured in tons for a commercial plant), what kind of ecological crap storm might you find yourself in if the then operator just walks away from it? Remember, our friend Senator Reed of Nevada was successful in killing the 30 billion dollar Yucca Mountain repository, so there is still no place to put irradiated/spent fuel.
Somebody in the US is going to actually design an ultra-safe, non-stupid theremal fission commercial reactor that we can build, cookie-cutter like, all over like the Franch have already done, and that design will be an economically viable plant. It may use something like a homogenous slurry system to periodically refuel it (no fuel rods, more like the ideal reactor with the fuel and neutron control features loaded in like a sand slurry). I never see a time when we will have a century's worth of fuel IN THE VESSEL. I also never see a time when someone outside of DOE or DOD will ever build a fast breeder in the US that could produce weapons grade fissiles as a possible side business.
You know, I could spell check, but then I would not appear to be as much of a bumpkin....
When you wrote
"Somebody in the US is going to actually design an ultra-safe, non-stupid thermal fission commercial reactor that we can build, cookie-cutter like, all over like the Franch have already done, and that design will be an economically viable plant. It may use something like a homogeneous slurry system to periodically refuel it (no fuel rods, more like the ideal reactor with the fuel and neutron control features loaded in like a sand slurry)."
you almost invented the liquid fluoride thorium reactor described in the Aim High article. Rather than a slurry, it uses LiF and BeF molten salts in which ThF is dissolved and converted to dissolved UF fuel. [Forgive the valence errors.]
B Dubya, nobody is making a breeder, and nobody is using water as a coolant or moderator. Did you even read the article?
Now, there are lots of ways we could use breeders (and become truly energy independent, including making liquid hydrocarbon fuels via thermal depolymerization) using just Uranium reactors. Or we could use liquid fluorine thorium reactors (which was so safe to run that for three years on weekends it was allowed to go into failure mode, monday they'd start it up and run it all week again), or this technology which has as the only long-lived byproduct Pa-231, a relatively benign alpha emitter (and you'd only open the case to get it every few centuries).
Sounds like a pretty good idea to me
No refueling for only a couple centuries?
What happens then?
Surely we can find something, somehow, more readily renewable
and truly sustainable.
Peak Uranium—238: Because it's only a matter of time before we run out of it.
But atoms are icky, and none of this will move us toward the eviro's goal of reducing us all to driving goat carts and living in mud huts. Therefore it will not be allowed.
Virtually any potential problem which may, or may not, occur a hundred or two hundred years down the road is not worth discussing unless there is an expectation that technical progress will stop a long time before then. And if technical progress stops or reverses the world there won't be enough population around to worry about some trivial scars of uninhabitable land.
Such discussions are similar to the idiocy surrounding worry about primitive savages opening up a nuclear waste site in ten thousand or a hundred thousand years. Why isn't someone designing non verbal signage to warn primitive savages about volcanos, sinkholes and the dangers of ten thousand year floods in river valleys? Why isn't someone designing signs to warn primitives of the danger of living in the path of glaciers?
"No refueling for only a couple centuries?
What happens then?"
Good plan. It's not perfect and doesn't magically make energy with no cost or resources so better not even try. After all, technology today is no different than 1800, so why would we possibly imagine it would be different in 2200?
The Soviet design for the RBMK-1000 (responding to the comment above) was horrible. It was extremely loosely coupled, neutronically speaking, had a very large positive void coefficient, and thus an overall positive power coefficient. An overall positive power coefficient is not allowed in the U.S. under the code of federal regulations.
The reactor designs will advance, but the ones we have now are just fine, regardless of whatever detractors and idiot environmentalists want to say about it. Refueling outages have become much more efficient and much shorter, containments are strong (unlike the RBMK-1000), and nuclear power remains the cleanest, safest source of energy available in the world today.
No one has to wait on "safe" designs. We already have them. No one has to wait on "new" designs. The ones we have work just swimmingly. In fact, no one has to design any more breeder reactors. Simply decide to undo the stupid, doltish Carter era commitments against reprocessing spent fuel, and the entire issue goes away (since LEU reactors at 4-5% U-235 are both critical and able to sustain power, and yet also produce Pu-239 from U-238).
The problem is not now and has never been technology. The problem is what it always is: politics and volition.
It didn't help that the Soviets were running the Chernobyl plant in excess of 100% of capacity *and* with some, most, or all of what safety devices they had disabled, either, I bet.
Note to Harry (Someone is squeezing my nuts) Reid. The French have been reprocessing fuel for decades but our "experts" say it MIGHT be dangerous. When are we going to kick these nincompoops in the butt and start doing things right?
I'm thinking that was deep, deep sarcasm on Jonathan Silber's part.
Sun Stu Nephew: "nobody is making a breeder'
Actually, the reactor in the article is a sort of breeder, it just does it very slowly, and burns that plutonium as it makes it.
Sort of a "Just in time" breeder.
This is all irrelevant, since Obama has decided to stealthily shut down the nuclear power industry by deep-sixing Yucca Mountain.
It's not his first atrocity.
There's a misunderstanding here. The Liquid Fluoride Thorium Reactor does not use U-238 because that is not fissionable. What they are doing is adding Neutrons to Thorium-232 which turns it into Protechtanium-233. If you merely remove the Protechtanium from the reactor and bubble some fluorine gas through it, it comes out of solution as Pr F6. All you need do then is store the gas for 27 days and it will become Uranium 233 which is fissionable. You dump this U-233 in the reactor and it fissions creating heat to run a helium gas turbine generator. The system should scale well from 50 to a 1000 megawatts. That is from a small to medium sized town to a major city.
What's nice about this system, is that it is safe. First of all, you can't make atom bombs out of it -- U-233 can't support a runaway reaction like U-235 or Plutonium can. Second. there is no catastrophic meltdown possible -- no China Syndrome. The Uranium-233 or U-235 are a liquid which expands as it gets hotter. You throw in Lithium or Boron fluoride to maintain the correct neutron density for fission. If the inner core gets too hot, it is self regulating, because the liquid expands so the neutron density decreases. As a fail safe in case you lose the load to your turbine generators, when the system gets above its design specifications the solid plug of Reactor mixture in the base melts and all the contents fall into a tray below the reactor where the reaction is stopped cold. When you fix what ever caused the power spike, then just pump the reactor mixture back into the reactor and the reaction starts heating up again. The scientists at Oakridge labs, where the system was developed, would shut it down for the weekend and start it up on Monday Morning.
The waste products of the reactor are much smaller and less dangerous than with a light water reactor. Instead of thousands of pounds of radio active waste, a One gigawatt reactor could run for a year and convert a ton of thorium into power while producing only ten pounds of radioactive waste. Moreover, the fission byproducts have a half life of 300 years instead of over 10 thousand years for a light water reactor. Since the reactor runs at normal atmospheric pressure no containment building is necessary. It could be placed in any commercial building. There is enough known deposits of Thorium in the US to supply the world's power needs for a thousand years.
No practical reactors have been built yet, although it is technically no more dangerous than for many high temperature industrial processes. I suspect that the US will not be building one, even though it will only cost about 200 million for a one gigawatt power plant. I expect Israel, Taiwan or China is more likely to attempt it since the Democrats want to starve America for power. Every means of generating power is a taboo for the Environmentalists in charge of our government. And nuclear power is a worst taboo for them than coal, oil or gas.
This is all irrelevant, since Obama has decided to stealthily shut down the nuclear power industry by deep-sixing Yucca Mountain.
Nuclear power is not the least bit dependant on Yucca. Yucca allways has been a political solution to a nonproblem. The best place to store spent fuel is in a dry cask in the parking lot. It'll keep there for several hundred years and we can revisit the issue then.
This talk about sustainable solar power really ticks me off. It is about time we called solar power the flawed energy source that it is obvious is: The sun is going to run out of power in a few billion years.
Also, we all know there's a finite source of protons and neutrons. Fusion power on this planet is no more sustainable.
Wind power won't work once all the atmosphere boils off of the planet. So wind power isn't sustainable either.
And geothermal? The planet is cooling. Geothermal will fail eventually.
We shouldn't embrace any energy source that is not sustainable - and that means forever!
I like the Lftr. The LFTR is a very simple, efficient, and elegant type of reactor. It can use any kind of nuclear fuel, bomb material, or nuclear waste product to produce very high temperature heat and at the same time breed more fuel in the bargain. This thrifty approach to nuclear energy greatly appeals to me, but I became even more interested in the LFTR when the details of a new patent were revealed by Dr LeBlanc. It opens up the possibility of building a reactor that can run for 30 years without refueling in an unattended mode, air cooled, sited underground while it breeds new fuel within the thorium structure of the reactor itself.
Yes, pure U233 can be used for bombs. But, in order to get to this U233 that has been produced inside the very walls of the reactor containment vessel, a proliferator must destroy the reactor, chop it up into small pieces while enduring heavy high energy gamma radiation exposure without being detected, then reprocess these reactor pieces using isotopic separation since the U233 is denatured with enough U238 to make chemical separation of bomb grade U233 impossible. Now, this is a tall order for any proliferator and may just be an impossible assignment.
At the end of the service life of the Lftr, the reactor vessel is sent back to the factory where it is reduced to liquid fluoride salts that become the feedstock of a next new Lftr. This feedstock can only be used by the new Lftr and not for bombs. The waste products are held at the factory for a few hundred years to cool down before they are mined for the many precious elements contained within like platinum and iridium. Now that’s what I call a safe, efficient and thrifty mode of operation.
The sun is going to run out of power in a few billion years.
So how are we going to deal with Peak Hydrogen?
What in tarnation, Randall Parker: Am I to understand you to be saying
that the sun will extinguish in a few billions years?
I need to short my stock in Hawaiian Tropic.
The liquid fluoride thorium reactor sounds like the way to go:
clean, safe, power that fights against tooth decay.
I am glad I could help you tune your stock portfolio in this manner. It makes blogging all that much worthwhile.
I would also suggest selling stock in agricultural industries since the lack of sunlight will cut crop production.
Yes, Peak Hydrogen. Good term. Glad you suggested it.
What I'm fervently hoping for: Peak Stupidity. I want to see the worst of it in our rear view mirrors.
I think our living standards will have to decline some before reality will intrude on policy deliberations. We'll probably repeat the experience of Britain where they blocked new coal and nuclear reactors for too long and now they look set to have a gap in their electric power generation capacity in the late 2010s. Though maybe they'll extend the operating lifes of some existing reactors to fill in their gap.
Robert Schwartz: "…evaluating energy options on the basis of the purity of their offerings to Gaia."
Now that, Mr. Schwartz, is hitting the nail on the head!
For two lengthy presentations on this subject, I would highly recommend the following Google Tech Talks. If you pay attention, they ought to help disabuse many on this thread of their ill-informed prejudices.
The Liquid Fluoride Thorium Reactor: What Fusion Wanted To Be
"Thorium is the third source of fission energy and the LFTR is the idealized mechanism to turn this resource into electrical energy. Enough safe, clean energy, globally sustainable for 1000's of years at US standards. This talk is aimed at explaining this thorium energy resource from fundamental physics to today's practical applications. The presentation is sufficient for the non-scientist to grasp the whole subject, but will be intriguing to even classically trained nuclear engineers. By providing the historical context in which the technology was discovered and later developed into a power reactor, the story of thorium's disappearance as an energy source is revealed. But times have changed, and today, thorium energy can be safely exploited in a completely new form of nuclear reactor."
Liquid Fluoride Reactors: A New Beginning for an Old Idea
"Since then he has been teaching at the Carleton University physics department and continued his investigations primarily in the field of Molten Salt Reactors, also known as Liquid Fluoride Reactors. David founded Ottawa Valley Research Associates Ltd to expand these efforts and has completed a license agreement with a European firm with a goal of development of a new generation of Molten Salt Reactors."
Robert Schwartz: "...evaluating enrgy options on the basis of the purity of their offerings to Gaia."
I find an incredible amount of dogmatic ignorance on the part of BOTH the radical left AND right. Many ignorant people of the extreme right-wing frown upon the Gaia Hypothesis with disdain to be some kind of pot- smoking hippie stoner religion from the late 1960s or something. Truth is, the Gaia Hypothesis is actually a very credible scientific hypothesis that the entire biosphere of the living planet is all one synergistic living organism where everything supports the survival of everything else.
And just who came up with this Gaia Hypothesis? None other than scientist James Lovelock himself,a rational and informed environmentalist(as opposed to the ignorant and stupid kind)who supports nuclear power as the savior of the planet. Considering all the catastrophic and less desirable alternatives(coal strip-mining,global warming,oil spills,and etc.),James Lovelock, the originator of Gaia, is indeed evaluating energy options on the basis of environmental purity offerings to Gaia ! ! !
Especially when considering Einstein's famous equation E=MC2 and the fact that uranium fission is the most high energy density fuel known to man, having 10,000 times more energy than burning the best quality anthracite coal. You can either strip-mine an entire thousand acres for coal.... or else immobilize nuclear waste in a water insoluble glass or ceramic object only the size of an aluminum Pepsi cola can. It's your choice, all you irrational Jane Fonda and Amory Lovins type of idiots.