India and Japan: News and Discussion

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Re: India and Japan: News and Discussion

Post by Naidu »

My heartfelt support and condolences to the Japanese people. Recover, rebuild and come back stronger than ever!

My local cable TV provider (Cablevision in NJ) is providing live feed of Japan's NHK TV on Ch 265. The scenes of destruction are pretty devastating. They are also playing the videos and pics captured by people from the effected areas.

I don't understand a word of Japanese, but no language is needed to understand this tragedy. :-(
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Re: India and Japan: News and Discussion

Post by joshvajohn »

It is sad that many people lost their lives in this disaster. I was surprised to see even Japan is not prepared to face this disaster. They need to be prepared for any eventualities similar to this. While facing disaster no country is spared whether rich or poor, it is better to be prepared.
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Re: India and Japan: News and Discussion

Post by astal »

Ramana, AmberG, YIP, Bade,

Thanks for your updates on the nuclear reactor related situation. From the looks of it there is no good news so far. Could any of you explain how and when the core will be cooled down enough to ensure that the containment vessel is not breached?
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Re: India and Japan: News and Discussion

Post by Amber G. »

....3) reactor is sub-critical, so reaction will not go out of control. Half the battle has already been won. In Chernobyl they could not lower moderator rods (they got warped and stuck) so meltdown happened through runaway reaction. This will not be a Chernobyl

(4) VERY IMPORTANTLY, if all else fails, they can dump moderator into reactor and shut down all heat decay permanently. This will kill the reactor, but it will also remove all source of heat i.e. decay of fuel rods
......

What they are doing is to "turn down the thermostat on water heater to vacation mode" so reactor can be brought back up as fast as possible. THEY ARE NOT YET FIGHTING A MELTDOWN.

....
May be of interest …. Perhaps control rod (neutron absorbers) is being confused with moderator (which slows down neutrons and actually help nuclear fission)

- Actually, moderator is needed for nuclear reaction and if (water used as moderator) boils away fission stops . United States (and now even Russian. After Chenobyl) reactors are all required by law to be slightly under-moderated. This way, if a catastrophic event occurred where all coolant was lost the reactor would shut itself down (like Three Mile Island)… Chernobyl was a graphite moderated reactor that used water only for cooling. Moreover, its prompt-temperature coefficient was positive. Now all reactors are required by law to have this coefficient negative. ( A negative coefficient means the hotter the core gets the more it wants to shut itself down).

The problem with Chernobyl control rods, which is well documented, was that its tips did not contain neutron poison (like boron or hafnium which the rods contain) but had graphite, a moderator which briefly increased the power before bringing it down.
Dumping down moderator will not stop the fission (actually opposite ie, removing all of it will stop it). Neutron poisons (eg boron etc) dumping will stop the fission, but, even if all the fission is stopped, there is no “removal of all source of heat”, the radioactivity of the fuel will keep it hot.. That’s why cooling it is very important (even when all the fission has stopped)!
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Re: India and Japan: News and Discussion

Post by Amber G. »

astal wrote: ..
Thanks for your updates on the nuclear reactor related situation. From the looks of it there is no good news so far. Could any of you explain how and when the core will be cooled down enough to ensure that the containment vessel is not breached?
It depends on the half life, and amount of fission products, which are radioactive (how long the reactor was in operation before shutdown, and the reactor type etc..) for this one the time period is measured in days (or a week).. when the cooling is done with full power.

Ramana will know more, but - if all else fails type scenario where one floods it with sea water the cooling period mentioned, I have seen, is about two days for this kind or reactor.

Another not so good news is that there is report of Cs radioactivity which, if true and if significant, is bad news.. (means there was a little melt down of the core..).
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Re: India and Japan: News and Discussion

Post by Hiten »

Nuclear plant issues in Japan are the least of their worries
......The almost certain scenario at all of the nuclear plants in Japan is that all of the hazardous material will be contained within the carefully engineered and constructed reactor pressure vessels and the surrounding containment building that were installed before the plants were ever started. During the course of events, there will almost certainly be a need for at least some of the the plant operators to carefully release non-condensible gases from their containment building. Some of those gases will be chemically inert "noble" gases that contain radioactive isotopes. No one will receive a high enough dose of radiation to cause any negative health effects.

Because standard water cooled nuclear reactors need to be supplied with more water as fission products decay and they cool down, their fuel can be damaged if the water is not delivered. Without water, even the ceramic fuel pellets that can withstand extremely high temperatures can melt. However, the fact that even moderately well trained nuclear specialists may not fully grasp is that the melted fuel is only generating enough heat to melt itself; it is not generating sufficient heat to melt through the thick steel pressure vessel where it resides....

The plant's containment dome will be contaminated as a result of being the reception location for the steam that boils away while the operators are trying to restore cooling flow. That water will have contacted the core and will contain some of the core material as the cladding gets overheated and damaged.

Radiation levels inside the containment will be many times higher than usual, but that is okay because no one needs routine access inside containment buildings and no humans will be over exposed. The containment walls, reactor coolant piping, and other equipment inside the containment building will condense and capture much of the radioactive materials that are entrained in the water. Other than those vented noble gases mentioned above, essentially nothing will be released to the environment.....

....There may well be some damage at the plant, but the damage will be contained as a result of the defense in depth strategy that is enabled in nuclear power plants because of the exceedingly compact nature of the fuel material. Since nuclear fuel is so compact and so inexpensive, we can afford to surround it with several protective layers and still produce power plants whose output is affordable and normally very reliable.....

In the Gannon Station case, the hydrogen for the explosion came from the cooling system for the very large electrical generator. Maintenance workers apparently did not ensure that the system was properly purged before opening it for maintenance.

My guess is that a similar generator cooling system was in use at Fukushima Daiichi. Considering the devastation that has occurred as a result of the earthquake and the tsunami, it would not be terribly surprising if the electrical generator cooling system developed some hydrogen leaks
. From what I have read about the actions taken to cool down the nuclear fuel inside the reactor, which is inside a robust containment building, not a steel frame building, I am guessing that the explosion had nothing to do with the heat source that normally supplies the the steam to turn the turbines that turn that electrical generator.
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Re: India and Japan: News and Discussion

Post by Theo_Fidel »

joshvajohn wrote:It is sad that many people lost their lives in this disaster. I was surprised to see even Japan is not prepared to face this disaster. They need to be prepared for any eventualities similar to this. While facing disaster no country is spared whether rich or poor, it is better to be prepared.
This is not the time for this. Very callous comments. :( :cry: No one can prepare for 9.0 type event. Best our technology can handle is 7.5. This is a physical limit.

Remember the Himalayas are known for 9.0's as well. It has been quiet for a long time. Sooner or later one will let go. Wonder what you will say about preparedness then.

As far as Three mile Island Unit 2 is still radioactive even though the fuel was removed decades ago. The coolant leaked radioactivity into the concrete, sub-structure and maybe some of the soil. The reactor itself has been entombed in concrete which has a life of hundred years or so while the radioactive particles have lives of thousands of years. This will be the long term legacy of this particular accident as well. Another dead tomb for radioactivity that will have to be monitored for centuries. Our children will be dealing with this site for centuries.
Last edited by Theo_Fidel on 13 Mar 2011 02:06, edited 1 time in total.
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Re: India and Japan: News and Discussion

Post by Y I Patel »

Thanks for correcting some sloppy writing.

If boric acid or some such material has to be used, would it be pumped in through the cooling loop, or directly into reactor core? Also, would that imply an irreversible shutdown of fuel rods, or could new fuel rods be inserted at a future date?

Of course, given all other stringent certification requirements for nuclear power, any of these actions would effectively imply that the unit will be shut down permanently.
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Re: India and Japan: News and Discussion

Post by astal »

Thank you for the information AmberG.

From:http://www.ctpost.com/business/article/ ... z1GQDs1ody
The blast destroyed the building housing the reactor, but not the reactor itself, which is enveloped by stainless steel 6 inches (15 centimeters) thick.

Inside that superheated steel vessel, water being poured over the fuel rods to cool them formed hydrogen. When officials released some of the hydrogen gas to relieve pressure inside the reactor, the hydrogen apparently reacted with oxygen, either in the air or the cooling water, and caused the explosion.

"They are working furiously to find a solution to cool the core," said Mark Hibbs, a senior associate at the Nuclear Policy Program for the Carnegie Endowment for International Peace.

Nuclear agency officials said Japan was injecting sea water into the core — an indication, Hibbs said, of "how serious the problem is and how the Japanese had to resort to unusual and improvised solutions to cool the reactor core."

Officials declined to say what the temperature was inside the troubled reactor, Unit 1. At 2,200 degrees Fahrenheit (1200 degrees Celsius) , the zirconium casings of the fuel rods can react with the cooling water and create hydrogen. At 4,000 degrees (2,200 Celsius), the uranium fuel pellets inside the rods start to melt, the beginning of a meltdown.

Chief Cabinet Secretary Yukio Edano said radiation around the plant had fallen, not risen, after the blast. Virtually any increase in dispersed radiation can raise the risk of cancer, and authorities were planning to distribute iodine, which helps protect against thyroid cancer. Authorities urged people within 12 miles (20 kilometers) of the reactor to leave.

Read more: http://www.ctpost.com/business/article/ ... z1GQDs1ody
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Re: India and Japan: News and Discussion

Post by Cosmo_R »

"Japan Floods Nuclear Reactor Crippled by Earthquake to Avert a Full Meltdown"

http://www.nytimes.com/2011/03/13/world ... ar.html?hp

Overall, given the double whammy (tsunami/earthquake), the Japanese have done remarkably well. The people are the real heroes--they did not panic, did what they were told to by authorities and displayed remarkable cohesion and discipline.

True there will be thousands dead and we will grieve for them. Nevertheless, imagine what the toll would have been in India. We would have had 5 million casualties and that too from stampedes to get closer to the epicenter to wonder at the destruction.

I am not a Japanophile but we are all Japanese now.
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Re: India and Japan: News and Discussion

Post by Amber G. »

..If boric acid or some such material has to be used, would it be pumped in through the cooling loop, or directly into reactor core? ..
From the press release
http://www.tepco.co.jp/en/press/corp-co ... 301-e.html
Plant Status of Fukushima Daiichi Nuclear Power Station (as of 2am March 13th)


All 6 units of Fukushima Daiichi Nuclear Power Station have been shut down.

Unit 1(Shut down)
- Reactor has been shut down. However, the unit is under inspection due to
the explosive sound and white smoke that was confirmed after the big
quake occurred at 3:36PM.
- We have been injecting sea water and boric acid which absorbs neutron
into the reactor core.

Unit 2(Shut down)
- Reactor and Reactor Core Isolation Cooling System have been shut down.
Current reactor water level is lower than normal level, but the water
level is steady. After fully securing safety, we are preparing to
implement a measure to reduce the pressure of the reactor containment
vessels under the instruction of the national government.

Unit 3(Shut down)
- Reactor has been shut down and we continue injecting water by High
Pressure Core Injection System. After fully securing safety, we are
preparing to implement a measure to reduce the pressure of the reactor
containment vessels under the instruction of the national government.
- Currently, we do not believe there is any reactor coolant leakage
inside the reactor containment vessel.

Unit 4 (shut down due to regular inspection)
- Reactor has been shut down and sufficient level of reactor coolant to
ensure safety is maintained.
- Currently, we do not believe there is any reactor coolant leakage inside
the reactor containment vessel.

Unit 5 (outage due to regular inspection)
- Reactor has been shut down and sufficient level of reactor coolant to
ensure safety is maintained.
- Currently, we do not believe there is any reactor coolant leakage inside
the reactor containment vessel.

Unit 6 (outage due to regular inspection)
- Reactor has been shut down and sufficient level of reactor coolant to
ensure safety is maintained.
- Currently, we do not believe there is any reactor coolant leakage
inside the reactor containment vessel.

Casualty
- 2 workers of cooperative firm were injured at the occurrence of the
earthquake, and were transported to the hospital.
- 1 TEPCO employee who was not able to stand by his own with his hand
holding left chest was transported to the hospital by an ambulance.
- 1 subcontract worker at important earthquake-proof building was
unconscious and transported to the hospital by an ambulance.
- The radiation exposure of 1 TEPCO employee, who was working inside the
reactor building, exceeded 100mSv and was transported to the hospital.
- 4 workers were injured and transported to the hospital after explosive
sound and white smoke were confirmed around the Unit 1.
- Presence of 2 TEPCO employees at the site are not confirmed

Others
- We measured radioactive materials inside of the nuclear power station
area (outdoor) by monitoring car and confirmed that radioactive
materials level is higher than ordinary level. Also, the level at
monitoring post is higher than ordinary level. We will continue to
monitor in detail the possibility of radioactive material being
discharged from exhaust stack or discharge canal. The national
government has instructed evacuation for those local residents within
20km radius of the periphery because it's possible that radioactive
materials are discharged.

- We will continue to take all measures to restore the security of
the site and to monitor the environment of the site periphery.
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Re: India and Japan: News and Discussion

Post by sanjaykumar »

As someone who finds much to appreciate in Japan, Indian PM's statement was very appropriate and certainly much more sincere sounding than some other countries'. Japanese society is quite remarkable-yet to see television images of hysterical survivors.
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Re: India and Japan: News and Discussion

Post by sanjaykumar »

Nevertheless, imagine what the toll would have been in India. We would have had 5 million casualties and that too from stampedes to get closer to the epicenter to wonder at the destruction.



We are like this only.
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Re: India and Japan: News and Discussion

Post by Cosmo_R »

sanjaykumar wrote:Nevertheless, imagine what the toll would have been in India. We would have had 5 million casualties and that too from stampedes to get closer to the epicenter to wonder at the destruction.



We are like this only.
I wish we were not.
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Re: India and Japan: News and Discussion

Post by joshvajohn »

Prime Minister offers India's help to quake-hit Japan
http://www.sahilonline.org/english/news ... &nid=10460

India stands in 'full solidarity' with Japan
http://www.google.com/hostednews/afp/ar ... 6306f8.371
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Re: India and Japan: News and Discussion

Post by Venkarl »

Image

So many lives :(
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Re: India and Japan: News and Discussion

Post by Bade »

The No3 plant unit (reactor) at Fukushima-I has declared an emergency too as per NHK world news this morning there. A total of 5 plantsunits at two different plants has now been declared at emergency level due to cooling issues. A Level 4 emergency on a scale of 0 to 7.

Cesium found outside No1 unit, so a partial meltdown confirmed. So fuel rod meltdown is being confirmed by NHK tv.

They also report at least 4 people exposed to radiation.
Last edited by Bade on 13 Mar 2011 04:21, edited 2 times in total.
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Re: India and Japan: News and Discussion

Post by Theo_Fidel »

sanjaykumar wrote:Nevertheless, imagine what the toll would have been in India. We would have had 5 million casualties and that too from stampedes to get closer to the epicenter to wonder at the destruction.



We are like this only.
Nagapattinam received a full 20 foot Tsunami and about 10,000 casualties, yet there was no panic and very little looting, etc. People pitched in helped each other with their bare hands and most orphans were adopted by relatives. If you went there today the coast is completely repaired and restored. It helps that we build with brick and plaster and not timber. Most pucca structures only needed a cleaning and fresh paint.

No need for own goals.

We are not like that only. :)
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Re: India and Japan: News and Discussion

Post by sanjaykumar »

Perhaps the time is right for a thread on the history of that event-its lessons but more importantly how the local inhabitants, relief and religious operations and rest of India reacted and coped.
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Re: India and Japan: News and Discussion

Post by Cosmo_R »

sanjaykumar wrote:Perhaps the time is right for a thread on the history of that event-its lessons but more importantly how the local inhabitants, relief and religious operations and rest of India reacted and coped.
Indeed and I hope you will make the effort. I promise to contribute FWIW
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Re: India and Japan: News and Discussion

Post by Amber G. »

Up to 160 may have radiation exposure in Japan nuclear accident
Nine individuals had already shown possible exposure to radiation from the plant, based on information from tests by municipal authorities and other sources, and estimates from the authorities suggested the figure could rise as high as 70 to 160, the official from the Japan Nuclear and Industrial Safety Agency told a news conference.
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Re: India and Japan: News and Discussion

Post by Amber G. »

Wrt to a question that how long the cooling is needed for the core after shutdown..
For sea water flooding/ cooling (I said before 2 days or so) the plan is about 10 days..
link ..
BTW simple calculation shows that typical fuel will produce around 10Kw/ton of decay heat even after a year..(one would still need passive heat sink!). For the reactor even after a week the heat output is about 0.2% of the power when it was running. (Just after shutdown the radioactive decay heat (beta decay of the fragments) is about 7% of heat(when reactor is working) and it goes down as time passes on... so it seems to me that one needs a good active cooling system for days/week(s) after shutdown.
Last edited by Amber G. on 13 Mar 2011 05:08, edited 1 time in total.
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Re: India and Japan: News and Discussion

Post by Gaurav_S »

Tried to find what GoI is doing to provide relief to Japanese. Are we sending any food, tents, medical etc there? Sending big team of manpower won't be perhaps best due to nuclear meltdown. I was expecting big relief to be sent there by India.

Was thinking like sending teams who have training dealing with nuclear exposure with full kit. Would show our support as well we will get fresh experience dealing with such disasters.
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Re: India and Japan: News and Discussion

Post by VenkataS »

If there is a chernobyl type disaster at one of these units, what would be the effect of that on the US west coast.

The north pacific jet stream carries winds from around Japan to the US west coast. Should people living on the US west coast be concerned and be prepared for some eventuality and fallout from this disaster.

[Added Later: To clarify, I live on the US west coast and from the TV coverage here was concerned that there might be some effect here as well. But my concern is nothing compared to what Japanese people near the affected area might be experiencing now.]
Last edited by VenkataS on 13 Mar 2011 09:05, edited 2 times in total.
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Re: India and Japan: News and Discussion

Post by sanjaykumar »

Yes it would be much more important to anticipate radiation fallout effects on white people than worry about the yellow ones being poisoned now.
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Re: India and Japan: News and Discussion

Post by Ambar »

I sincerely hope US west coast will not be impacted in anyways. My ears are already bleeding with CNN and FOX screaming about ONE confirmed death of a US citizen, and how US is rushing 7 ships to Japan. They repeat this every 10 mins, it makes you wonder about the self-importance and narcissism of some human beings.
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Re: India and Japan: News and Discussion

Post by svinayak »

Ambar wrote:I sincerely hope US west coast will not be impacted in anyways. My ears are already bleeding with CNN and FOX screaming about ONE confirmed death of a US citizen, and how US is rushing 7 ships to Japan. They repeat this every 10 mins, it makes you wonder about the self-importance and narcissism of some human beings.
This is a psychological image creation during the time of fear and uncertainty.
This kind of high pitch news will establish some authority and sense of control over the gobal arena.
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Re: India and Japan: News and Discussion

Post by Bade »

I switched to NHK for the last 2 hours and though the imagery is more devastating than what is shown by CNN/Fox the voice is more soothing and detailed. It is in English too. Don't know why I did not watch them before.

CNN is so jarring had to turn the tv off in the morning. CNN/Fox new reports had no people (local) in it. Streets were shown as empty in the i-reports, maybe because they were recorded immediately following the quake. No pics of rescue attempts and briefing by local officials.
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Re: India and Japan: News and Discussion

Post by ramana »

AmberG and YI Patel, Normal reactor water has boron injection to moderate the reactor. Boric acid is added in tanks containing the water.

Early on I speculated the hydrogen was formed by disassociation. That seems to be the case. The flooding of the containment bldg to cool the reactor down is good idea. The normal shutdown also would be the same thing dump borated water through pumps.

NHK can be seen in Bay Area TV KCSM 60 in program Newsline.

NHK is very clear and balanced in its coverage without hype or hysteria.

Bay Area radio and TV is whining about a few boats being tossed around in Santa Cruz harbor and some dude who got washed away while taking pictures of the waves. And as usual iflating the damage. Some guy was claiming 30,000 patrons lost business as he ha to shut down under govt orders!

I think the reactor shutdown will be just a matter of time. Need to ensure the water doesnt overflow and contaminate the surroundings.

AmberG, There is a branch called Health Physics that deals with radiation dosage.
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Re: India and Japan: News and Discussion

Post by ramana »

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Re: India and Japan: News and Discussion

Post by Amber G. »

Ramana - I was talking about Boron in the control rods (which is a good neutron poison like Cadmium, Hafnium etc). In BWR type reactors, boron in water is not a moderator but more like control rod (to adjust the rate of reaction - eg ..to shut down the reactor or to accommodate short term transients such as changes to load on the turbine, etc..).
(Added wiki link later )

(Moderator (eg water, heavy water, graphite etc) - slows down neutron to thermal velocity, so that fission can continue...
Neutron poison (eg Cd, Boron etc) absorbs neutron and stops fission. )

BTW boron (as impurity) was the main cause Germans were unsuccessful around WWII. Their graphite moderators failed to work because it had boron impurity which absorbed the neutrons.. (Fermi & Co used highly pure graphite)..They never discovered this problem, and were forced to use far more expensive heavy water moderators...(Fortunately for US . Szilard discovered the problem - of boron prperty - and graphite used in Fermi's pile was free of boron)

In Chernobyl, ironically, the control rods which were Hf and Bo, had graphite tips.. and when controllers put them in, the graphite actually sped up the fission (instead of shutting it down) which finally resulted in blowup. (moderator and poison should not be confused :) )

Also there has been some talk about venting steam/vapor .. that as I said before, with filters does not contain much radioactivity.. (Things like radioactive Nitrogen has very short half life) and really of not much concern. Leakage of Cs etc is... (Reports of partial melt down of the core)

Added later: From wiki:wiki (Normally there is no boron in BWR coolant water.. in PWR some use it like control rods)
..., BWRs have no boron in the reactor coolant and control the reactor power by adjusting the reactor coolant flow rate.
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Re: India and Japan: News and Discussion

Post by Amber G. »

xpost
NRao wrote:Japan Scrambles to Avert Meltdown After Another Nuclear Reactor Fails
Japanese officials announced Sunday that the cooling system at a second nuclear reactor crippled by Japan’s devastating earthquake had failed completely, even as they took the extraordinary step of flooding a separate reactor with seawater in a last-ditch effort to avoid a nuclear meltdown.
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Re: India and Japan: News and Discussion

Post by vera_k »

How is it that the containment structure for the reactor can be destroyed so easily?
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Re: India and Japan: News and Discussion

Post by Amber G. »

^^^According to reports I have seen - Containment structure(s) at all Fukushima plants are intact.
(Where do you hear otherwise?)
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Re: India and Japan: News and Discussion

Post by Y I Patel »

Thanks for the education!

Once boron is inserted as poison, would the fuel rods be usable at a later date, or are they coated by poison and therefore ruined for good?

I assume salt water in such a hot environment will be exteremely corrosive and will damage a lot of the piping.

Taken together, looks like the two will kill the reactor for good. Am I correct in that interpretation?

Also, if the water decreases and BWR has negative voids coefficient fission rate should go down in any case, correct? I read that with Western designed reactors this one feature ensures that even total meltdown will not cause containment chamber to be breached. However, I also read that there is controversy surrounding that issue.
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Re: India and Japan: News and Discussion

Post by vera_k »

I was looking at the photo in this article where the internals are shown exposed to the elements.

Second nuclear meltdown likely under way in Japan
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Re: India and Japan: News and Discussion

Post by Singha »

I think saving the reactor parts for future would be last thing on anyone's mind. containing the fallout and stabilizing the issue would 1st and last priorities right now.

japan can manage fine without a power plant or two - they have plenty.
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Re: India and Japan: News and Discussion

Post by Y I Patel »

That is true. However, Tokyo Electric Power Company, which owns the reactors, has been operating on the tract to save reactors for later use. When things looked like they were getting out of control, then they pulled the trigger to kill the reactor. At least that is what I think has been happening, and I wanted to confirm that.
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Re: India and Japan: News and Discussion

Post by devesh »

is this the second coming of Matthew Perry for Japan? it will take a monumental effort by Japan to repair the damages done. and they don't have a vibrancy they once did. it will be interesting to see how Japan copes and takes care of the disaster. for now, condolences to the nation and hopes and wishes for a quick recovery.
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