Ed Lizard Posted March 12, 2011 Share Posted March 12, 2011 I'd have designed the plant with passive cooling, ie, natural circulation, as well as redundant systems, if I was building one in an area known for strong quakes. As soon as a reactor is scrammed, it continues producing about 7% of the average power production of the previous several days of operation because of radioactive decay of unstable isotopes produced by fission. This decay heat then declines. http://www.rertr.anl...EV1/TDHEAT.html (Former NEC 3383, surface ship reactor operator, ET2/E-5 before I went to college) Link to comment Share on other sites More sharing options...
ArtRosen Posted March 12, 2011 Share Posted March 12, 2011 http://www3.nhk.or.jp/daily/english/12_38.html The operation at Fukushima No.1 plant to lower pressure of the containment vessel has been suspended due to high radiation levels at the site. Pressure of the reactor container is rising as its cooling system became dysfunctional due to a blackout and power generator breakdown. This has raised concern about possible damage to the container. The power station's operator, Tokyo Electric Power Company, began to vent air from the reactor container at 9AM on Saturday. Under the plan, 2 valves close to the container would be opened manually, but radiation level on the second valve was found higher than expected. The operation has been suspended because of the possibility that workers could be exposed to radiation. The utility is reportedly studying how to open the valve by replacing workers at a short interval, or using electric remote control. The Nuclear and Industrial Safety Agency says if radioactive substance is released in the air, safety of residents evacuated beyond a 10-kilometer radius from the No.1 reactor will be ensured. Saturday, March 12, 2011 13:09 +0900 (JST) Link to comment Share on other sites More sharing options...
Ed Lizard Posted March 12, 2011 Author Share Posted March 12, 2011 I'd have designed the plant with passive cooling, ie, natural circulation, as well as redundant systems, if I was building one in an area known for strong quakes. As soon as a reactor is scrammed, it continues producing about 7% of the average power production of the previous several days of operation because of radioactive decay of unstable isotopes produced by fission. This decay heat then declines. http://www.rertr.anl...EV1/TDHEAT.html (Former NEC 3383, surface ship reactor operator, ET2/E-5 before I went to college) Thread merge? http://www.americanwx.com/bb/index.php/topic/15243-possible-partial-or-full-nuclear-meltdown-as-a-result-of-89-earthquake-in-japan/ Link to comment Share on other sites More sharing options...
baroclinic_instability Posted March 12, 2011 Share Posted March 12, 2011 Thread merge? http://www.americanw...quake-in-japan/ Threads merged. Link to comment Share on other sites More sharing options...
Nikolai Posted March 12, 2011 Share Posted March 12, 2011 I'd have designed the plant with passive cooling, ie, natural circulation, as well as redundant systems, if I was building one in an area known for strong quakes. As soon as a reactor is scrammed, it continues producing about 7% of the average power production of the previous several days of operation because of radioactive decay of unstable isotopes produced by fission. This decay heat then declines. http://www.rertr.anl...EV1/TDHEAT.html (Former NEC 3383, surface ship reactor operator, ET2/E-5 before I went to college) I'm pretty sure the Japanese know more about building nuclear power plants in earthquake-prone areas than you do... just hazarding a guess... It's too bad you weren't around to help out with Chernobyl either because that *totes* wouldn't have melted down if the Soviets had followed your advice. Link to comment Share on other sites More sharing options...
Scott747 Posted March 12, 2011 Share Posted March 12, 2011 http://www.chron.com...ll/7469065.html A nuclear power plant affected by a massive earthquake is facing a possible meltdown, an official with Japan's nuclear safety commission said Saturday. Ryohei Shiomi said that officials were checking whether a meltdown had taken place at the Fukushima Daiichi power plant's Unit 1, which had lost cooling ability in the aftermath of Friday's powerful earthquake. Shiomi said that even if there was a meltdown, it wouldn't affect humans beyond a six-mile (10-kilometer) radius. Link to comment Share on other sites More sharing options...
ArtRosen Posted March 12, 2011 Share Posted March 12, 2011 http://www.chron.com...ll/7469065.html A nuclear power plant affected by a massive earthquake is facing a possible meltdown, an official with Japan's nuclear safety commission said Saturday. Ryohei Shiomi said that officials were checking whether a meltdown had taken place at the Fukushima Daiichi power plant's Unit 1, which had lost cooling ability in the aftermath of Friday's powerful earthquake. Shiomi said that even if there was a meltdown, it wouldn't affect humans beyond a six-mile (10-kilometer) radius. How do they calculate that? Link to comment Share on other sites More sharing options...
LovintheWhiteFluff Posted March 12, 2011 Share Posted March 12, 2011 no, it turns out we weren't delivering after all... Japan refused the offer or something... http://blogs.wsj.com...oogle_news_blog That's my point exactly. Of course Japan refused our offer. The coolant is WATER. They have plenty of that there. Link to comment Share on other sites More sharing options...
Scott747 Posted March 12, 2011 Share Posted March 12, 2011 How do they calculate that? Because to this point it's contained. Link to comment Share on other sites More sharing options...
ArtRosen Posted March 12, 2011 Share Posted March 12, 2011 I'm pretty sure the Japanese know more about building nuclear power plants in earthquake-prone areas than you do... just hazarding a guess... It's too bad you weren't around to help out with Chernobyl either because that *totes* wouldn't have melted down if the Soviets had followed your advice. The nuclear power plants at risk were built in the 1940s and are first generation, old power plants. They may know more now, as in 2011, but I highly doubt they knew more then. Link to comment Share on other sites More sharing options...
Rick G Posted March 12, 2011 Share Posted March 12, 2011 IF the containment building is breached, then we will need to know the wind patterns around the plant. if the worse case happens then we will have what is called a China Syndrome. where the reactor core melts through the bottom of the reactor vessel and hits the water that is under ground. the water then flashes to steam and that pushes through the top of the reactor. this will spread radiation and radioactive particles for hundreds of miles. this is what happened in Chernobyl. this isn't something that can be cleaned up. Link to comment Share on other sites More sharing options...
Ed Lizard Posted March 12, 2011 Author Share Posted March 12, 2011 I'm pretty sure the Japanese know more about building nuclear power plants in earthquake-prone areas than you do... just hazarding a guess... It's too bad you weren't around to help out with Chernobyl either because that *totes* wouldn't have melted down if the Soviets had followed your advice. You'd hope they would. Chernobyl, my understanding was it was a poorly planned and perhaps not authorized experiment, in a style of reactor plant perhaps not used in the US since the Manhattan Project itself. I didn't design passive cooling/natural circulation of course, but I've know about it since I was at the Knolls Atomic Power Laboratory in New York about twenty five years ago. And I'd think every civilian nuclear reactor should be designed to maintain coolant flow in case of loss of power. Your experience with nuclear power? Link to comment Share on other sites More sharing options...
ArtRosen Posted March 12, 2011 Share Posted March 12, 2011 Because to this point it's contained. Everything I'm seeing says there's a meltdown about to occur.. Another link.. http://english.aljazeera.net//news/asia-pacific/2011/03/20113124353222667.html Link to comment Share on other sites More sharing options...
LovintheWhiteFluff Posted March 12, 2011 Share Posted March 12, 2011 I'm pretty sure the Japanese know more about building nuclear power plants in earthquake-prone areas than you do... just hazarding a guess... It's too bad you weren't around to help out with Chernobyl either because that *totes* wouldn't have melted down if the Soviets had followed your advice. Chernobyl happened because they didn't have the proper containment buildings setup in case of an emergency. The Japanese plants are like the US plants in that they have a containment building to hold in the radiation if they have a meltdown. This Japanese plant would be similar to Three Mile Island, not Chernobyl. Link to comment Share on other sites More sharing options...
JoMo Posted March 12, 2011 Share Posted March 12, 2011 A 'meltdown' would likely be contained in the containment building. The presence of cesium is what set off the 'uh oh, this may be melting down' alarms. Link to comment Share on other sites More sharing options...
jburns Posted March 12, 2011 Share Posted March 12, 2011 IF the containment building is breached, then we will need to know the wind patterns around the plant. if the worse case happens then we will have what is called a China Syndrome. where the reactor core melts through the bottom of the reactor vessel and hits the water that is under ground. the water then flashes to steam and that pushes through the top of the reactor. this will spread radiation and radioactive particles for hundreds of miles. this is what happened in Chernobyl. this isn't something that can be cleaned up. Being blown to the east would be the best case scenario. Link to comment Share on other sites More sharing options...
MJW155 Posted March 12, 2011 Share Posted March 12, 2011 Chernobyl happened because they didn't have the proper containment buildings setup in case of an emergency. The Japanese plants are like the US plants in that they have a containment building to hold in the radiation if they have a meltdown. This Japanese plant would be similar to Three Mile Island, not Chernobyl. Except there are numerous reports that the containment buildings may be damaged from the earthquake. This can end up being a much bigger deal than what happened at 3 Mile. Link to comment Share on other sites More sharing options...
Ed Lizard Posted March 12, 2011 Author Share Posted March 12, 2011 If these reactors are from the 1950s and 1960s, I'm surprised they hadn't been decommissioned. After about 30 years operating at full power, the containment vessel experiences something called neutron embrittlement. I know the A4W/A1G reactors on the CVN-68 (Nimitz) class were expected to last about 40 years, or be refueled a single time. They last a little longer because the reactors are almost never at full power, and are usually shut down in port. If I'm not mistaken, the Enterprise (CVN-65) which has an older design power plant, will soon be retired, mainly because its reactor plants are nearing the end of useful service life. Link to comment Share on other sites More sharing options...
Scott747 Posted March 12, 2011 Share Posted March 12, 2011 Everything I'm seeing says there's a meltdown about to occur.. Another link.. http://english.aljaz...4353222667.html There could still be a 'meltdown' and containment at the same time. Don't equate this to Chernobyl which many folks will probably initially think when they see the word 'meltdown. A better equation at this state is TMI. Link to comment Share on other sites More sharing options...
ineedsnow Posted March 12, 2011 Share Posted March 12, 2011 why on earth would someone build one of these plants so close to the ocean where something like this can happen!! STUPID! Link to comment Share on other sites More sharing options...
Bozart Posted March 12, 2011 Share Posted March 12, 2011 Being blown to the east would be the best case scenario. Obviously. And we've got about a sh*t-pile of mets on here. Can ONE of them tell us what the winds are doing, and are forecast to do? Link to comment Share on other sites More sharing options...
ArtRosen Posted March 12, 2011 Share Posted March 12, 2011 http://www.straitstimes.com/BreakingNews/Asia/Story/STIStory_644342.html TOKYO - JAPANESE quake-hit nuclear plant Fukushima No. 1, located about 250km north-east of Tokyo, 'may be experiencing a nuclear meltdown', Kyodo and Jiji news reported on Saturday. Parts of the reactor's nuclear fuel rods were briefly exposed to the air after cooling water levels dropped through evaporation, and a fire engine was pumping water into the reactor, Jiji Press reported. The water levels are recovering, said operator Tokyo Electric Power, according to Jiji. Link to comment Share on other sites More sharing options...
janetjanet998 Posted March 12, 2011 Share Posted March 12, 2011 PER NHK: Cessium and Iodine have been detected around the Fukoshima One plant. Up to 1 1/2 meters of fuel rods may have been exposed, and water levels are sinking in the plant. If I recall correctly Cessium and Iodine are products of a nuclear reaction ....so something has happened Link to comment Share on other sites More sharing options...
Ed Lizard Posted March 12, 2011 Author Share Posted March 12, 2011 http://www.straitsti...ory_644342.html TOKYO - JAPANESE quake-hit nuclear plant Fukushima No. 1, located about 250km north-east of Tokyo, 'may be experiencing a nuclear meltdown', Kyodo and Jiji news reported on Saturday. Parts of the reactor's nuclear fuel rods were briefly exposed to the air after cooling water levels dropped through evaporation, and a fire engine was pumping water into the reactor, Jiji Press reported. The water levels are recovering, said operator Tokyo Electric Power, according to Jiji. The plants are not fixable if that is true. Exposure to air, which doesn't transfer heat readily, will almost certainly lead to swelling of the matrix (usually niobium) the uranium fuel is contained in, and possible blistering or even rupturing of the cladding of the fuel rods. Link to comment Share on other sites More sharing options...
Ed Lizard Posted March 12, 2011 Author Share Posted March 12, 2011 Distribution of iodine pills would seem to be in order anywhere near there. The thyroid gland takes up iodine, and loading the body with iodine will reduce the amount of radioactive iodine isotopes the thyroid would otherwise take up. Link to comment Share on other sites More sharing options...
patrick05 Posted March 12, 2011 Share Posted March 12, 2011 Obviously. And we've got about a sh*t-pile of mets on here. Can ONE of them tell us what the winds are doing, and are forecast to do? i'm not a met but looking at JMA, there's a high pressure area in the region and the winds look like variable at 5-10mph... look at this map for Fukushima: http://www.jma.go.jp/en/amedas/205.html?elementCode=1 Link to comment Share on other sites More sharing options...
LovintheWhiteFluff Posted March 12, 2011 Share Posted March 12, 2011 Except there are numerous reports that the containment buildings may be damaged from the earthquake. This can end up being a much bigger deal than what happened at 3 Mile. From the Science Media Centre of Canada: John Luxat, Professor and Industrial Research Chair in Nuclear Safety Analysis, McMaster University says: What seems to have happened at the Fukushima nuclear plant? “It’s very difficult to make definite conclusions at this point because information is coming in bits and pieces. What we do know is that when the quake hit the reactors at Fukushima, there were three of the reactors up and running – the other three were shut down for regular inspection. The three that were up and running immediately shut down, as they are designed to do when the ground shakes above a certain level. “The emergency backup diesel generators that provides electricity to the shutdown cooling system operated as designed for about an hour, and then they failed for some reason that’s not clear. They lost power to the pumps providing cooling water. Reports are that they have brought in backup generators and hooked them up. “One reactor is reported to have a slightly greater problem with cooling, which is not fully clear. “At this stage, they need to reestablish the electrical power supply to the cooling system. “The other thing is that the containment buildings haven’t suffered any reported damage. The plants are designed to strict seismic requirements because they’re in an earthquake region in Japan, and there’s no reported damage to these structures. The function of a containment building is to contain any radioactive material released from the reactor and limit any subsequent release outside the plant.” http://www.scienceme...christchurch-2/ Link to comment Share on other sites More sharing options...
ArtRosen Posted March 12, 2011 Share Posted March 12, 2011 TMI was not a full meltdown in one unit. Right now, we're talking *5* units in Japan that could fully meltdown. Three mile island was also brought under control... it does not look like this will be brought under control. Link to comment Share on other sites More sharing options...
Bozart Posted March 12, 2011 Share Posted March 12, 2011 i'm not a met but looking at JMA, there's a high pressure area in the region and the winds look like variable at 5-10mph... look at this map for Fukushima: http://www.jma.go.jp...l?elementCode=1 Thank you for that link. A nice strong west-to-east fetch would have been good to see. Bears watching. Link to comment Share on other sites More sharing options...
Ed Lizard Posted March 12, 2011 Author Share Posted March 12, 2011 why on earth would someone build one of these plants so close to the ocean where something like this can happen!! STUPID! The ocean is a big heat sink needed to cool the steam that has passed through the turbines back to feed water. Almost every big reactor is built near a lake, river or ocean. Link to comment Share on other sites More sharing options...
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