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clancy688 said:Don't know if that was posted here before:
http://www.mod.go.jp/j/approach/defense/saigai/tohokuoki/temp.html
Daily thermal images from the reactors.
why the hot spots in the turbine bldgs?
clancy688 said:Don't know if that was posted here before:
http://www.mod.go.jp/j/approach/defense/saigai/tohokuoki/temp.html
Daily thermal images from the reactors.
tsutsuji said:I would like to know it too.
The generators Exelon is using in the United States are :
And locomotives are air-cooled, aren't they ?
Perhaps, with so many variables it is hard to predict. IMO - the only certain system would be something powered by the reactor heat in the event of electrical failure.Joe Neubarth said:A pipe was not in my thoughts.
But if the whole island moved about eight feet or more, a pipe would be fine.
Krikkosnack said:Tsunami Warnings/Advisories
http://www.jma.go.jp/en/tsunami/
A strong earthquake with a preliminary magnitude of 7.1 shook buildings in Tokyo and a wide swathe of eastern Japan on Monday, with an advisory for a one-meter tsunami issued after the quake. reuters
AntonL said:It is now downgraded to 6.6 but most interesting it triggered a swarm of nine aftershocks within two hours, a 5.2 only ten minutes later followed four minutes later by a 4.7
Whereas, the 7.1 quake on 7 April had two 4.6 aftershocks about an hour later and the third 7.5 hours later
http://earthquake.usgs.gov/earthquakes/recenteqsww/Maps/10/140_35_eqs.php
AntonL said:Follow Up: the swarm of aftershocks continues 22 aftershocks in 8 hours !
compare this to 67-22 = 45 for the week preceding todays 6.6 event
something is rumbling beneath the Earth - any seismologist here?
Now a new study from Hiroshima and Kyoto Universities has found that the radioactive content of soil samples beyond the 30 km semi-evacuation zone is as much as 400 times the normal. From Asahi: "The predicted changes in the level of radiation at the ground surface were calculated after analyzing the amounts of eight kinds of radioactive materials found in the soil and taking into consideration the half-lives of each material. The study results are considered more accurate than the study conducted by the science ministry, which only released information concerning two types of radioactive material. [Scholars] collected soil samples from five locations in the village at depths of five centimeters. All the locations were outside the 30-km radius and were by roadways in various hamlets. The study found cesium-137 at levels between about 590,000 and 2.19 million becquerels per cubic meter." Comparing this to Chernobyl: "After the Chernobyl nuclear accident in the former Soviet Union in 1986, residents who lived in areas where cesium-137 levels exceeded 555,000 becquerels were forced to move elsewhere. The amounts of cesium-137 found in Iitate were at most four times the figure from Chernobyl."
timeasterday said:Yes, they are radiator cooled. They mention "locomotive-sized" which I take it to mean very big. The larger generators we make (>3MW) typically use remote-mounted radiators unless they are CHP applications.
artax said:No, they could have used that water for emergency cooling of the reactors AFTER the damage instead of sea water. Sorru... hadn't followed the previous threads very comprehensively!
Some images just released... mostly terrible resolution!
http://cryptome.org/eyeball/daiichi-npp6/daiichi-photos6.htm
Joe Neubarth said:...when millions of lives are at stake ...
tsutsuji said:This sounds close enough to the "D/G Inoperable due to Tsunami flood" analysis on page 12 of http://www.nisa.meti.go.jp/english/f...110406-1-1.pdf and professor Yoshiaki Oka's analysis :
Emergency DGs started at the earthquake. But Tsunami damaged ultimate heat sinks (sea water pumping and cooling system) of units 1F1-4. caused common cause failure
ivars said:
|Fred said:Considering that at d + almost 30 , they aren't any closer to restore cooling , if anything situation is worse , containment is not really containing , what option do they have ? They can't let it bleed out for ever ...
Astronuc said:Here is another good overview of the Fukushima event.
www.vgb.org/vgbmultimedia/News/Fukushimav15VGB.pdf
a core melt might be a cleaner solution than a continues feed and bleed, only if it can be guaranteed that the molten core does not go critical, and to prevent a steam explosion the dry well must dry which it is not.TCups said:3) Prepare to let the cores melt and deal with the consequences.
TCups said:An interesting question, indeed. Posited another way: If the emergency efforts to cool the reactor cores are (and it would seem, can only be) a temporary solution as long as the coolant (water) is not contained in a closed system,
Then only three alternatives exist:
1) Continue to spill contaminated water and slowly (relatively) contaminate the ground water and ocean while temporizing. (possibly, to allow time to deal with the spent fuel in the SFPs?), or
2) Somehow devise a stable, permanent system to contain, decontaminate and if possible, recirculate the water being used for cooling the cores (unlikely), or
3) Prepare to let the cores melt and deal with the consequences.
Is there another option I am missing? If not, then option (3), it seems, is most likely the "not if, but when" final event in the Fukushima disaster sequence.
Which begs the question: What might be done while temporizing with the current efforts to cool the cores to mitigate the ultimate consequences of one or more melted reactor cores with loss of the primary containment? If the answer to that question is "nothing effective", then, is option (1) with ongoing contamination by un-contained, highly contaminated water for as long as humanly possible worse than option (3)?
I don't know.
http://www3.nhk.or.jp/daily/english/12_05.htmlThe Japanese government's nuclear safety agency has decided to raise the crisis level of the Fukushima Daiichi power plant accident from 5 to 7, the worst on the international scale.
The Nuclear and Industrial Safety Agency made the decision on Monday. It says the damaged facilities have been releasing a massive amount of radioactive substances, which are posing a threat to human health and the environment over a wide area.
Pheesh said:Well it's now basically official, I guess they just felt like skipping 6!
http://www3.nhk.or.jp/daily/english/12_05.html
TCups said:An interesting question, indeed. Posited another way: If the emergency efforts to cool the reactor cores are (and it would seem, can only be) a temporary solution as long as the coolant (water) is not contained in a closed system,
Then only three alternatives exist:
1) Continue to spill contaminated water and slowly (relatively) contaminate the ground water and ocean while temporizing. (possibly, to allow time to deal with the spent fuel in the SFPs?), or
2) Somehow devise a stable, permanent system to contain, decontaminate and if possible, recirculate the water being used for cooling the cores (unlikely), or
3) Prepare to let the cores melt and deal with the consequences.
Is there another option I am missing? If not, then option (3), it seems, is most likely the "not if, but when" final event in the Fukushima disaster sequence.
Which begs the question: What might be done while temporizing with the current efforts to cool the cores to mitigate the ultimate consequences of one or more melted reactor cores with loss of the primary containment? If the answer to that question is "nothing effective", then, is option (1) with ongoing contamination by un-contained, highly contaminated water for as long as humanly possible worse than option (3)?
I don't know.
TCups said:Is there another option I am missing?
|Fred said:Considering that at d + almost 30 , they aren't any closer to restore cooling , if anything situation is worse , containment is not really containing , what option do they have ? They can't let it bleed out for ever ...
shogun338 said:RPV temperatures remain above cold shutdown conditions in all Units, (typically less than 95 °C). In Unit 1 temperature at the feed water nozzle of the RPV is 228 °C and at the bottom of the RPV is 121 °C. In Unit 2 the temperature at the feed water nozzle of the RPV is 149 °C. The temperature at the bottom of the RPV was not reported. In Unit 3 the temperature at the feed water nozzle of the RPV is 92 °C and at the bottom of the RPV is 111 °C. With the temperature being over 428 degrees Fahrenheit at the feed nozzle does this indicate that fission is still occurring inside Unit 1 ? http://www.iaea.org/newscenter/news/tsunamiupdate01.html
Astronuc said:The temperatures on Unit 1 are puzzling, and the Unit 3 temperatures are problematic.
http://www.f.waseda.jp/okay/news_en...ower_Plants_suffered_big_eart_quake110331.pdf
Pg5
Emergency DGs started at the earthquake. But Tsunami damaged ultimate heat sinks (sea water pumping and cooling system) of units 1F1-4. caused common cause failure
•Without ultimate heat sink, Emergency DG (need to remove its generated heat for operation) and spent fuel pool cooling do not work.
Pg6
2:46pm: The earthquake happened. Plants automatically shut down. Offsite power lost. Emergency DG started up.
•3:42pm Emergency DG(diesel generator) stopped due to loss of equipment cooling water. (Tsunami was bigger than expected.) All AC power was lost for 1F1-4 and consequential isolation from UHS(ultimate heat sink), except for IC (isolation cooling system) in 1F1. RCIC(reactor core isolation cooling system) in 1F 2 Blackout + (mostly) loss of UHS"