the FBR
will use mixed plutonium-uranium oxide as fuel in its core, with a blanket of depleted uranium oxide that will absorb neutrons and transmute into plutonium 239
by dean 1/23/2012 12:10:19 AM
coolant for the FBR will be liguid sodium which is a very volatile solution
by dean 1/23/2012 12:11:01 AM
In fast reactors, the core isn't in its most reactive--or energy producing-- configuration when operating normally. Therefore, an accident that rearranges the fuel in the core could lead to an increase in reaction rate and an increase in energy production. If this were to occur quickly, it could lead to a large, explosive energy release that might rupture the reactor vessel and disperse radioactive material into the environment.
by dean 1/23/2012 12:11:31 AM
Many of these reactors also have what is called a "positive coolant void coefficient," which means that if the coolant in the central part of the core were to heat up and form bubbles of sodium vapor, the reactivity--a measure of the neutron balance within the core, which determines the reactor's tendency to change its power level (if it is positive, the power level rises)--would increase; therefore core melting could accelerate during an accident. (A positive coolant void coefficient, though not involving sodium, contributed to the runaway reaction increase during the April 1986 Chernobyl reactor accident.)
by dean 1/23/2012 12:12:06 AM
In contrast, conventional light water reactors typically have a "negative coolant void coefficient" so that a loss of coolant reduces the core's reactivity.
by dean 1/23/2012 12:12:30 AM
That sounds rather hard to control. Has there been any sort of challenge to the safety assumptions for fast breeder reactors? As in has anyone said they can't be run unless certain things are resolved and have a safety mechanism to solve that particular risk?
by lillymunster 1/23/2012 12:15:30 AM
@lilly.. this may be a prototype reactor but the plans were to build many of the 1200 Megawatt ones
by dean 1/23/2012 12:19:36 AM
More largely, international experience shows that fast breeder reactors aren't ready for commercial use. Superphénix, the flagship of the French breeder program, remained inoperative for the majority of its 11-year lifetime until it was finally shuttered in 1996.
by dean 1/23/2012 12:20:52 AM
Concerns about the adequacy of the design of the German fast breeder reactor led to it being contested by environmental groups and the local state government in the 1980s and ultimately to its cancellation in 1991. And the Japanese fast reactor Monju shut down in 1995 after a sodium coolant leak caused a fire and has yet to restart. Only China and Russia are still developing fast breeders. China, however, has yet to operate one, and the Russian BN-600 fast reactor has suffered repeated sodium leaks and fires.
by dean 1/23/2012 12:23:12 AM
thebulletin.org further reading @lilly
by dean 1/23/2012 12:24:15 AM
Monju had such an expensive dangerous mess when they jammed a tool in the reactor. Makes me wonder what the potential energy output vs. total cost of these reactors is.
by lillymunster 1/23/2012 12:24:25 AM
well I think the first indian FBR is only 500 MW and is a prototype, overall expense is much greater... I claim that there are other reasons like plutonium production that drive the decisions rather than the savings on fuel
by dean 1/23/2012 12:27:52 AM
en.wikipedia.org @lilly.. good article on the breeder reactor not far from where I worked
by dean 1/23/2012 12:29:49 AM
if fukushima reactors would have been sodium cooled and had gone through what they did I just can't imagine how much worse things would have been
by dean 1/23/2012 12:32:31 AM
@dean do fast breeders require constant power?
by lillymunster 1/23/2012 12:35:56 AM
Radioactive substances in the air dropped...because now they are in everything else
ajw.asahi.comby lillymunster 1/23/2012 12:43:11 AM
Ohio gozaimasu all
by bo 1/23/2012 12:48:44 AM
hi Bo!
by lillymunster 1/23/2012 12:56:23 AM
@lilly.. yes and heat for the sodium
by dean 1/23/2012 1:08:38 AM
@Ron.. yes it wuld be the same for the fuel but the fuel configuration is different in FBR's , typically commercial fuel elements need to get to a point where they are generating a low enough heat that they won't boil water without cooling or in the case of dry storage, won't be too hot to cause damage to the fuel element once it's in the cask
by dean 1/23/2012 1:25:31 AM
@Ron, I believe that commercial fuel has to be stored in the spent fuel pool for a year or more prior to movement in a cask or storage in a cask
by dean 1/23/2012 1:33:32 AM
www.nucleartourist.com @ Ron, this is a good article on fuel cooling, it is longer than a year (sounds like 10 years) in the article before the fuel elements can be stored in the cask and have air cooling
by dean 1/23/2012 1:36:35 AM
@Ron, looks about right, I believe that fresh fuel from the reactor goes to one sfp grid and then cools and is then moved to another area in the canal to await cooling to either be moved to the general storage canal via a cask and short trip to the building usually close by and they further cooling to meet the cask design specifications
by dean 1/23/2012 1:40:47 AM
will return
by dean 1/23/2012 1:46:48 AM
Davis-Bessie dividing the Democratic candidates in an Ohio congressional district. Kuinich fighting a long time anti-choice nut:
www.deseretnews.comby bo 1/23/2012 2:07:20 AM
@bo Someone should look into Kaptur's campaign donations. The abrupt change of stance on the nuclear plant sounds like it came with a healthy donation...
by lillymunster 1/23/2012 2:21:38 AM
@lilly Kaptur is one of the Blue Dog Dems who sabotaged Obama's health care bill. I have no doubt she walks around with a price tag on her forehead.
by bo 1/23/2012 2:22:49 AM
www.tms.org good write up on concrete use at NPR's
by dean 1/23/2012 2:23:11 AM
Suspected contaminated concrete, use at six hospitals -
www.yomiuri.co.jpby lillymunster 1/23/2012 2:26:49 AM
www.tampabay.com New crack at Crystal River nuclear plant casts doubt on repair plan nov-2011 report
by dean 1/23/2012 2:30:40 AM
via twitter feldspar, a flux used in ceramics is produced in Fukushima. Someone was sending out cautions on origin of products people use in making ceramics. I don't know if this is a local issue or if this is larger production that they produce and ship it elsewhere.
by lillymunster 1/23/2012 2:36:37 AM
@lily there are many sources of feldspar. It's just that this has to be removed from sale, which we know is not guaranteed.
by bo 1/23/2012 2:47:52 AM
5.0 quake in Hawaii - depth 8km
earthquake.usgs.govby lillymunster 1/23/2012 2:48:29 AM
by lillymunster 1/23/2012 3:19:21 AM
@lilly, oh yes, I'm all over it. I have the 2004 Gojira release, but I know the Criterion version will be much crisper.
by bo 1/23/2012 3:22:59 AM
@bo I don't think I have seen the unedited one yet. They always play the Raymond Burr one here.
by lillymunster 1/23/2012 3:26:39 AM
@lilly they are completely different movies. The original Gojira is very political and very anti-nuclear. The American one with Raymond Burr strolling around in it is just a hack monster movie.
by bo 1/23/2012 3:29:17 AM
Heading to my office. Back on soon.
by bo 1/23/2012 3:40:21 AM
Shimane NPP shuts down Jan 27
mdn.mainichi.jpby lillymunster 1/23/2012 3:42:22 AM
1seg mobile TV may be used for emergency broadcasts in the future
mdn.mainichi.jpby lillymunster 1/23/2012 3:43:13 AM
Bombing Antarctica
trove.nla.gov.au by lillymunster 1/23/2012 4:05:04 AM
So NHK knew but were told to keep quiet! ex-skf.blogspot.com Sunday, January 22, 2012
@dean for spent fuel rods in a typical US/Japan nuke power plant, how long do you need water cooling before you could put the fuel rods in dry cask storage? Would a fast breeder need a similar cooling time?by RonD 1/23/2012 1:21:17 AM
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