Fukushima's No. 2 reactor may be reheating

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  • 1

    some14some

    The utility said it will check the accuracy of the thermometer in question, as two others on the same reactor have been measuring its temperature at around 35 degrees.

    defective thermometer? made in Japan, i guesss. well it might not be due to global warming either. It will be sfe to assume 'cause under investigation.'

  • 5

    JeffLee

    “Rather than the actual temperature rising, we believe there is high possibility that the thermometer concerned is experiencing display error,” he said.

    Um, right. Now now Tepco has lost the ability to monitor the basic situation inside the reactor. How reassuring.

  • 13

    zichi

    I think the temperature is measured by a thermocouple device, and not a thermometer. It could be defective or even damaged by the probe TEPCO recently inserted to try and locate the melted fuel, which it failed to do.

    The temperature is reading between 82 to 92degC, depending on which source you want to accept. There's a 20degC error margin, which even at the lower temperature of 82degC, would put it above 100degC, the limit set by the government to call it a "cold shutdown" or "safe shutdown ".

    The rad levels inside the reactor building remain very high, above 400 microsieverts/hr, too high to send a worker to check the thermocouple device.

    This event, reminds us all the fragile nature of the badly damaged reactors and supporting plant. Even calling the NPP in "safe shutdown" is walking something of a knife edge.

    There'll be hundreds or even thousands of similar events over the coming decades before the plant can be called safe, if ever?

    Even though the plant remains in a fragile condition, the government is planning to allow some of the people from the no-zone to return to their homes and communities, which in my opinion, would be the wrong decision.

  • 2

    NetNinja

    May be reheating?? Now more like they're turning it on. After it's on again they'll be like..."Look, it's running safely"

    J/K It's a terrible situation and the worst is yet to be discovered.

  • 2

    tamanegi

    Maybe might possibility...just the facts please!

  • 1

    tkoind2

    And we should trust your statements why?

  • 3

    Charles M Burns

    “We believe the state of cold shutdown is being maintained,” TEPCO spokesman Junichi Matsumoto told a press conference.

    Well, that's comforting...

  • 6

    escape_artist

    Just a quick "thank you" to zichi and some others for their helpful & thoughtful posts. I like following a discussion where I can walk away feeling like I've learned something.

  • 2

    yildiray

    I have never seen a thermometer malfunction...have you?

    How many thermometers have you seen working in highly radioactive surroundings?

  • 1

    SquidBert

    I have never seen a thermometer malfunction...have you?

    Yes, especially if they are exposed to heat way beyond their operating specifications. Which is likely here. But then again, thermocouples used in a NPPs should be set up so they have predictable failure modes. Which would mean that they should be able to tell a functioning thermocouple from a bad one?

    I think Zichi, might have some experience with industrial processing, so maybe he has some input on this?

  • 5

    YongYang

    Cold shutdown was not can not be achieved at any of the three units suffering meltdowns / melt throughs. A Corium mass sat on / eating through its concrete mat is not a viable state to define a reactor, whic is needed for a cold shutdown. The announcement that it was was an appalling affront to honesty, a lie to the world. All this ad-hoc dead ending process is doing is creating more radioactive waste and lulling the easily fooled into a sense of false security. THe catastrophe is STILL a Level 7. That's 3 Level 7s. Storage Pool No 4, well, that could take us to a new dimension, IF it collapses and one thing we HAVE to ahve learned is... That's right. The Corium mass is heating up, a self sustaining reaction very possible. Keep an eye on what is going on, will we get some truth? Exhale now, no point waiting. My thoughts, respect and thanks AGAIN to those working to save us still.

  • 2

    Elvensilvan

    These keep nagging my mind:

    Is the current increase in temperatures caused by the broken flanges and leakages last week? Exactly where in the reactor are the thermometers, specifically this "defective" one? Is it closer to the fuel, to the floor, the water? Can't they put in a new thermometer inside the reactor, just to make sure?

    I mean, they were able to punch a hole for an endoscope, why not use the same hole to insert a thermometer and double-check?

  • 2

    tchanglee

    I don't quite beleive what they say. There is always something not mentioned. This news is to condition public's opinion before reporting something nasty - radiation leaks to water, air, etc.

  • 0

    Sarcasm321

    They're softening us up for something more scary, classic PR tactic of drip-feed info so that the shock of the "big" news isn't so great. I urge the readers of JT who live in Japan and have children TO GET OUT NOW and stop risking your kids' health. This is serious guys, c'mon.

  • 5

    zichi

    SquidBert,

    I'm a former electrical engineer and instrumentation, measurement and control engineer with extensive experience in the heavy chemical industry, but none with nuclear reactors.

    The point is, first this reactor was damaged by the earthquake, cracking open the suppression chamber. Followed by a total meltdown of the nuclear fuel creating temperatures in the thousands of degrees. This will have distorted the reactor and damaged all the instrumentation.

    There are just so many unknowns and much of what is going on is nothing more than educated guess work with trial and error.

  • 0

    Charles M Burns

    The utility said it will check the accuracy of the thermometer in question, as two others on the same reactor have been measuring its temperature at around 35 degrees.

    I assume this hasn't been done already because it is difficult to do? Would seem like step number 1, before injecting tons of additional water.

  • 0

    Puff_the_Magic

    BURY IT!

  • -1

    Paul Arenson

    And all this points to another problem....the govt has been inviting reporters in to cover life as it supposedly gets back to normal....and they (JAEA) have first told reporters to don protective suits, then when the reporters entered the area, they did an about face and said it would agitate people, so please remove them, they said. And they have succeeded in removing radiation from 100 to 60 micro sievert in one case, but at the expense of using sub sub sub sub contractors and risking their health... And that is still a high figure. Rather better to make it like Chernobyl and keep it a forever no go zone. Decontamination is a publicity stunt. But that works against their plan to create the image that all is ok.....to pretend that the damage done is not as bad as it is, to rebuild confidence, to avoid the country going non nuclear. I think better to write off a large area of Fukushima. You cannot blame local people when they get angry that others shun them in a repeat of Hirishima syndrome...these people have no choice because the govt does not extend evacuation areas and all is voluntary. But neither can you blame people who are wary of products from the area, when there is no strict testing regime.... And so as Tepco and the govt play one against the other, they succeed in dividing the citizenry. As Zichi and others say, this thing will go on and on for a long time. People who have left are now as far as Miyazaki where we live, trying to rebuild their lives. People who have stayed are now having trouble where to place their anger-at those who left or at the corporation and govt which betrayed them. There is no easy way to deal with their rage, but the criminal acts of Tepco and the govt must be kept in full focus. Even now they are threatening to ban protestors who are camped out in front of METI....they want to wish anti nuclear sentiment away. And any real attempt the dangers will be swept under the rug so as to create the illusion of normalcy. A country which has still not addressed the lingering issues stemming from Minamata disease cannot be expected to act with morality here either.

  • 2

    SquidBert

    @Zichi,

    I get what you are saying, I have some education along the same lines but ended up doing other things in life. Still it is surprising to me that they are not able to diagnose whether or not the thermocouple is still working. My point being here, that the accuracy of the thermocouples that are measuring 35 something degrees is not question by TEPCO, while the one that is reading an 'uncomfortable' level immediately gets its accuracy questioned.

    On a different topic, as Paul Arenson is saying here, it took more than 35 years before the government even began recognizing Minamata disease as being caused by the mercury released from the Chisso corporation. At least mercury exposure to the body can be proven long after it's occurrence. With radiation exposure we are not as lucky, so it will be very difficult for someone to prove that their symptoms 10,20,30 years down the line is related to a specific event. And I bet that the nuclear industry/government is very thankful for that.

  • 1

    Harry_Gatto

    As Meatloaf said, "Two out of Three ain't Bad". Maybe, however the facts will out soon but how reliable these facts are remains to be see.

  • 1

    Fadamor

    IMHO, a thermocouple with a documented temperature variance of +/-20°C is worthless. Why even bother if the actual temperature is in a 40°C bracket around the indicated reading? The thermocouple on my school's weather station has a +/-2.5°F variance. Something's not right.

  • 0

    Samantha Ueno

    Hope people held on to their potassium iodide tablets from the first scare.

  • 0

    Elvensilvan

    If the variance of thermocouples is at +/-20°C, then who knows, all the thermocouples may be correct after all!

    35 + 20 = 55 82 - 20 = 62

    So they're not that far apart!

    Sarcasm aside though, I hope TEPCO and the Japanese government have made provisions ... just in case kind of scenarios. With TEPCO's track record of mismanagement, and the Japanese government's reluctance in disclosing several facts from the general public (I know, to avoid mass panic situations), it's kind of getting hard to trust both of them in terms of proper nuclear management.

  • 3

    zichi

    When the temperature of the reactor reaches an indication of 80degC, TEPCO is required to report the event to the prefecture governor and must continue with hourly updates until it drops again. All temperatures reported by TEPCO, are the indicated ones.

  • 0

    Patrick Hattman

    “Rather than the actual temperature rising, we believe there is high possibility that the thermometer concerned is experiencing display error,” he said.

    Yeah, right, it must be a faulty thermometer.

  • -1

    NetNinja

    Now my question is this: Is it going to blow?

    I'm serious.

    Is this thing going to physically explode? It's reheating means they are NOT in control.
    Cooling down = Good Reheating = Bad

  • -5

    japan_cynic

    Yet more scaremongering from the tinfoil hatters. Don't you guys get tired of all the hyping? Sure, it's a problem, but the simple fact is that this accident has not, and will not, kill many people. Campaign against mochi if you really want to save lives.

  • 0

    hanataro

    reheating, i think so. they just pump in the water but the whole thing is leaking. the temperature meters should be proper if they get the same data from more thermometers. they should be careful with the temperature. Now is around 80 degress celsius. At the 80 the water is already damping with the radiation as well. At TEPCO are they only amateurs, i think

  • 0

    nandakandamanda

    I guess they are constantly in two minds. They will be believing one scenario but preparing for the other just in case.

    Let's hope they are not just believing the scenario that the thermocouple is malfuctioning because it is easier to deal with.

    Let's hope that common sense prevails there and they have a Plan B.

  • 0

    gifu

    No backup thermometer? !

  • 2

    Darren Brannan

    Went up to 94 degrees. Tepco now claim 'it's broken' yet the other two 'aren't' so they aren't going to 'test' the other two. That is the 'truth'. According to Tepco and NISA. The guys who supply vital data to the US before Japanese citizens.

  • 0

    SetagayaObserver

    We will see this kind of trouble for decades, at least! There is only one way for Japan- turn off and dismantle all the other Plants, store the Fuel in a safe Place until we will find a way how to handle this Pandora Box!

    Maybe Thorium-Reactor are a way to go- maybe not!

    Todays Radiation: 0.145uSv/h at Groundlevel in Setagaya-Ku

  • -2

    Utrack

    The thermocouple may not be broken because watching video footage it looks like it is so hot the clouds evaporate above reactor 2 on Tepco live camera and the heating gauge indicating 276.4℃ now.

    http://fukushima-diary.com/2012/02/cloud-is-erased-above-reactor-2-on-tepco-live-camera/

  • 0

    Utrack

    Another heating gauge on reactor 2 is showing increasing temperature, It’s attached to the Control Rod Drive Housing, which is under the container vessel. It's shows increasing temperatures along with the "broken guage". the diagram is on Fukushima Diary.

  • 0

    nandakandamanda

    I have read reports today of over 300 degrees and over 400 degrees. Apart from the broken gauge theory, I read in a Q&A with Tepco that there could be a lump of corium stuck to one wall which is not getting the direct trickle of water it was getting before.

    Also, SetagayaObserver, I saw that the Governor of Shizuoka has suggested Hamaoka be dedicated to research into Thorium reaction in place of Uranium. Chugoku Denryoku (Chuden) replied that they know nothing about Thorium and anyway it would be the government's decision to make, not theirs. Interesting article here.

    http://www.chunichi.co.jp/article/shizuoka/20120212/CK2012021202000005.html

    Tepco continue to deny any detection of Xenon gas (which should be given off with re-criticality), which leads them to the conclusion the gauge itself is bust..

  • -1

    Star-viking

    Utrack Feb. 13, 2012 - 09:33PM JST

    The thermocouple may not be broken because watching video footage it looks like it is so hot the clouds evaporate above reactor 2 on Tepco live camera and the heating gauge indicating 276.4℃ now.

    Look, if there really was an actual reading of 276.4℃ we would also see an increase from the other two thermocouples, which we are not.

    http://fukushima-diary.com/2012/02/cloud-is-erased-above-reactor-2-on-tepco-live-camera/

    Wrong link - that's about TEPCO 'erasing clouds'... the conspiracy deepens!!!

  • -1

    Star-viking

    UtrackFeb. 13, 2012 - 10:21PM JST

    Another heating gauge on reactor 2 is showing increasing temperature, It’s attached to the Control Rod Drive Housing, which is under the container vessel. It's shows increasing temperatures along with the "broken guage". the diagram is on Fukushima Diary.

    This page: http://fukushima-diary.com/2012/02/another-heating-gauge-is-showing-increasing-temperature/

    The CRD readout spikes twice in January and February without a response from the broken gauge, so I doubt the link is as solid as Fukushima Diary makes out. Indeed, for a few days it reads zero degrees or lower, with no response at all from the broken gauge. There's a chance that something affecting the CRD could cause the rise in the broken gauge - but not the other way around. Pretty moot as the broken gauge's resistance has been found to be changed from the baseline.

  • 0

    Utrack

    Star_Viking there is an increase in another guage it's the Control Rod Drive Housing, which is under the container vessel.

  • 3

    zichi

    Untrack

    Your recent comments have taken on a strange twist like suggesting millions of Japanese should leave the country.

    Now you are stating that the reactor is so hot that the heat is evaporating passing overhead clouds?

    Firstly, I watched the video and there would be no way to know if the passing clouds are directly above the reactor or many miles/ kilometers further away. Secondly, do you have any idea how hot it would have to be to evaporate clouds thousands of feet up. Well I don't, but I think it would have to be tens of thousands of degrees. In fact so hot, the reactor itself would have melted. That scenario couldn't have even happened at the peak of Chernobyl.

    I have been following the Fukushima Diary for a month or so but I'm not impressed by it.

    We're are you getting the temperature of 276 from?

  • 0

    Utrack

    the inside of the reactor is a mess, so I would assume some areas may not be as hot as others.

  • 0

    nandakandamanda

    Yahoo reported the temperature of 276 and above and this evening said the temps went off the top of the scale.

    Tepco has been measuring the 'resistance' of the hot gauge, but has no plans to check the resistance of the cold gauges, apparently. (Fukushima Diary) So, which is/are broken and which is/are working?

    The translations at Fukushima Diary are not good enough to reflect what the original Japanese is saying. I can get much more meaning from the Japanese than from the strange, stilted and sometimes mistaken English. Better than nothing? Hmmm... No, not always.

  • 0

    nandakandamanda

    Reported on Yahoo, but taken from the Yomiuri:

    http://headlines.yahoo.co.jp/hl?a=20120213-00000878-yom-sci

  • -1

    hoserfella

    Once again, If there's one thing I've learned from this thread it's that the worlds foremost nuclear experts reside right here on JT. And if there's one thing I can learn from them, it's "panic". I will start burying everything I see tomorrow morning..

  • -2

    Star-viking

    UtrackFeb. 13, 2012 - 10:53PM JST

    Star_Viking there is an increase in another guage it's the Control Rod Drive Housing, which is under the container vessel.

    Yes, re-read my posting and replace the "CRD" you see there with "Control Rod Drive Housing" and it will make more sense.

  • 1

    almostshat

    "Stringent new safety standard"! Laugh? I almost choked on my mochi. And no mention in this article of the 20 degree margin for error in these temp readings. How stringent is that! (82+20= ??? OK, still well below 100 degrees then; I was worried there for a minute)

  • 3

    zichi

    Last month 60 workers drilled a hole in the side of the containment vessel to insert a probe.

    The same hole could be used to insert a thermocouple without difficulty and could even be done by a Quince robot?

    TEPCO changed the water cooling system to use the recycled water from the treatment plant instead of fresh supply which adds to the total of waste water. The water jet system may not be working as before? A lump of corium might be struck to the side of the pressure or containment vessel which was being cooled but no longer is? The probe should have spotted that lump if it was inside the containment vessel?

    If the temperature is at 270degC, surly TEPCO would be able to see steam leaking from the reactor?

  • 0

    Utrack

    Zichi, these two sites are where it says the temp is 276

    http://fukushima-diary.com/2012/02/another-heating-gauge-is-showing-increasing-temperature/

    http://ex-skf.blogspot.com/2012/02/tepco-evening-press-conference-2132012.html

  • 0

    Utrack

    Star_viking I had not refeshed my page so I did not see your second post before I posted my comment to your first post.

  • 0

    Utrack

    My apologies it was on the ex-skf blog only the 276

  • 3

    zichi

    Untrack,

    That's not hot enough to evaporate passing overhead clouds?

  • 0

    Utrack

    If nothing is wrong then Why would TEPCO do this : At 1:29 pm on February 13, we ( Tepco ) started injection of hydrazine to spent fuel pool of Unit 2 through the circulating cooling system.

    http://www.tepco.co.jp/en/press/corp-com/release/12021306-e.html

  • 0

    Utrack

    Zichi

    Okay It's was a bogus video. It was a shock to see though with all that's going on and I have not changed I have always wanted people to get out of harms way. It is just that the contamination is spreading.

  • 1

    Fadamor

    I'm normally not a scare-monger and have tried to tamp-down some of the silly rhetoric that has been posted here in the past, but the fact that the reactor is warming up instead of cooling down IS of primary concern. The heating in reactors are controlled by shielding the fuel rods as needed. With the fuel rods melted and presumably sitting on the bottom of the containment vessel, there is no way to accurately control the temperature. Running cooling water through the containment vessel is only cooling the surface of the corium but not doing much for the coruim underneath. I guess the hope was that the fuel rods had not congregated to the point that little surface area was getting cooled by the water. With the water heating up even though water has been flowing continuously, it looks like that hope was unfounded. This. Is. Not. Good.

  • 2

    zichi

    Yesterday, at a press conference, TEPCO basically stated that thermocouple was busted?

    TEPCO announced on February 13 that the thermocouple on the bottom of the Reactor 2 Pressure Vessel at Fukushima I Nuclear Power Plant, which had been showing the rising temperature, exhibited the abnormal temperatures after the inspection in the afternoon on February 13, at one time going overscale over 400 degrees Celsius which is the limit.

    TEPCO thinks it is "most certainly broken". The thermocouple had been exposed to high temperature from the core meltdown, and has been in the high humid condition [inside the Reactor 2 Containment Vessel].

    http://ex-skf.blogspot.com/2012/02/fukushima-i-nuke-plant-additional-info.html

  • -2

    Star-viking

    UtrackFeb. 14, 2012 - 12:54AM JST

    If nothing is wrong then Why would TEPCO do this : At 1:29 pm on February 13, we ( Tepco ) started injection of hydrazine to spent fuel pool of Unit 2 through the circulating cooling system.

    From wikipedia: http://en.wikipedia.org/wiki/Hydrazine

    A quote:

    "Hydrazine is used within both nuclear and conventional electrical power plant steam cycles to control concentrations of dissolved oxygen in an effort to reduce corrosion."

  • -3

    Star-viking

    UtrackFeb. 14, 2012 - 01:02AM JST

    Okay It's was a bogus video. It was a shock to see though with all that's going on and I have not changed I have always wanted people to get out of harms way. It is just that the contamination is spreading.

    As Zichi pointed out, it's not a bogus video - the interpretation is bogus.

    As for the contamination spreading, the radioisotope emission is down to one thirteen millionth of the initial release, and is around the level of a coal-burning power plant.

  • -2

    Star-viking

    FadamorFeb. 14, 2012 - 01:08AM JST

    I'm normally not a scare-monger and have tried to tamp-down some of the silly rhetoric that has been posted here in the past, but the fact that the reactor is warming up instead of cooling down IS of primary concern. The heating in reactors are controlled by shielding the fuel rods as needed. With the fuel rods melted and presumably sitting on the bottom of the containment vessel, there is no way to accurately control the temperature.

    Two out of the three thermometers appear to be working normally, and would certainly show an increase if there actually was excessive heating going on in the vicinity of the third reactor - after all, they are sitting in the same pool of water.

    There's a very small chance that the other two are the ones that are bust - but the chances of them breaking at the same time, and in the same manner (i.e. continuing to show similar readings) is remote.

  • -2

    Star-viking

    By the way, we might have a good contender for the steam we were discussing earlier:

    From Utrack's link http://www.tepco.co.jp/en/press/corp-com/release/12021306-e.html

    At 10:07 am on February 8, we stopped the operation of the secondary cooling tower in order to prevent overcooling of alternative cooling system of spent fuel pool of Unit 3. Afterward the temperature of the water of the pool was increased so we operate the secondary cooling tower at 10:08 am on February 13.

    Cooling Towers.

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