Japanese solution?

Discussion in 'General Science & Technology' started by universaldistress, Mar 15, 2011.

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  1. universaldistress Extravagantly Introverted ... Valued Senior Member

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    What is the solution to the nuclear power station fiasco in Japan?

    We all wonder why the hell the diesel generators failed when they surely should be encased in a very sturdy enclosure. Was the generator's exhausts the weakness do you think?

    How do they move forward? The water needs to get into the reactor core. I suppose their setup isn't designed for modern cooling fluids as such.

    Is there a danger of a meltdown melting radioactive material down into the earth, through the crust? What under ground cooling sytems are they likely to have in place anyway?

    Do they need to crane some big structures back over the reactors (where buildings have now gone) and vent the hydrogen into the ocean. Could this help to prevent the ejection of heavy radioactive material into the atmosphere?

    Would forest firefighting planes be of any use if the reactors did meltdown, in stopping said ejection?

    Lastly. Do you guys think that if one reactor meltsdown the whole lot are bound to follow?
     
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  3. cosmictraveler Be kind to yourself always. Valued Senior Member

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    First this is what an actual meltdown looks like , this was taken at the Chernobyl plant that went bad.


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    This was covered up by over a thousand tons of concrete to insure no leaks will take place at least while it is covered in all that concrete.

    Since we don't know the extent of the problems with each reactor in Japan it is hard to discuss ways to either "fix" them or cover them up. They will need to evaluate each reactor and then determine what to do.

    A airplane dropping water wouldn't get much directly onto the reactor core nor be of much help. A helicopter with a bucket full of water would be better for it can get the water directly onto the core but again it isn't much use because it needs thousands of gallons of water to cool it down over many hours if not days.

    To move forward they will have to determine what needs to happen with each reactor and if they can get the pumps working again or get a temporary way to put allot of water onto the core as they are doing with sea water now on one of the reactors.
     
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  5. Fraggle Rocker Staff Member

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    The largest firefighting plane is a 747 operated by the American company Evergreen. It has a capacity of almost 100,000 liters--more than 25,000 gallons. There's only one of those and the next largest is a Russian plane that's just about exactly half as big. It takes about an hour to refill the tanks on the Russian plane; I have no figures for the American plane.

    Both of them were recently in Israel, fighting a disastrous fire near Mt. Carmel that I never even heard of.

    I'll let you do the math and calculate how much help it would be to send those planes to Japan. I have no idea whether 150,000 liters is a lot of water in this context.

    I suspect it might not be so helpful since they can't hover and pour all the water on one relatively small area.
     
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  7. universaldistress Extravagantly Introverted ... Valued Senior Member

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    Yeah, it seems like it could be an ask too much possibly. I was wondering whether snow making machines would be of any use, or even dumping ice cubes or blocks across the site. I suppose the need for anything like that is dependent on the rods being exposed, as until that happens it isn't going to help, and possibly just hamper the means of pumping water into the core. I presume it is a tricky job to keep the water flow just right and takes a human finger at the controls?

    They tried helicopters dropping water already (bbc news website) but radiation was too high apparently. I did wonder why they didn't just hover higher but then thought it was probably an aim concern again. They could drop ice cubes from higher with greater accuracy if the winds died down I suppose.

    What about lifting the reactors up and dropping them in the sea? Or dangling them from a helicopter winch into the sea, spose the risk is too great. Pity we can't just click our fingers and send them over to antarctica. They say chernobyl wildlife has really benefitted from the rads.

    Couldn't they just dump tonnes of concrete over the whole thing and call it a day? What are the implications of the meltdowns being allowed to continue unabated, despite risk of ejection of radioactive material?
     
  8. universaldistress Extravagantly Introverted ... Valued Senior Member

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    The radioactive material can reach 3,400 degrees centigrade. The concrete will decompose below that I believe. I think I read somewhere that they had means of cooling the ground using water underneath chernobyl but I am not sure if this is correct or not. They did cap chernobyl with thousands of tonnes of concrete but not sure how soon after the incident they were able to pour it.
     
  9. Read-Only Valued Senior Member

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    They haven't provided any details about the backup generators - just that they were "knocked out" by the earthquake. They did bring in mobile generators but couldn't hook them up because of "mismatched connectors." Gee, whatever happened to just using cables and bypassing those stupid connectors???

    All in all, seems to me a major case of overconfidence on the part of the plant management - and that's REALLY stupid when you consider the critical purpose/need for backup systems. They are supposed to be redundant - backups for the backups. Failure to provide that is what I'm calling really stupid.

    As far as the long-term solution goes, it will depend upon the individual conditions at each of the reactors.
     
  10. universaldistress Extravagantly Introverted ... Valued Senior Member

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    One more obvious thing into the mix; what the hell were they doing building reactors on that side of the country. There must have been some reason for that. BIG mistake.

    Surely the stations (due to the fact a lack of a constant flow of water to the core causes big problems, quick) should have an independent, reliable power source that is protected underground? Why the hell did they lose power anyway as the reactor was still going and it should be able to make enough energy to supply its water pumps anyway. They did say the problem emanated from a lack of power? :shrug:
     
    Last edited: Mar 16, 2011
  11. Rhaedas Valued Senior Member

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    First thing they are designed to do in an earthquake is to insert the control rods and cease power production to begin cool down. This they all did correctly.
     
  12. universaldistress Extravagantly Introverted ... Valued Senior Member

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    And then they lost the power for the pumps. Ahhh. maybe they should have kept one reactor online?
     
  13. Rhaedas Valued Senior Member

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    The objective is to get it shut down so they can assess any damage, plus prevent some of what's happening now. What should have been done was to make sure the generators and their backups would not fail at all. I don't think we have yet the full facts of why they did fail and what could have been done about it, although the correlation between the tsunami arrival time and when they went out match up pretty well.
     
  14. John99 Banned Banned

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    Obviously they weren't high enough. The buildings survived the quake.
     
  15. DeeCee Valued Senior Member

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    "What is the solution to the nuclear power station fiasco in Japan?"

    For now bury it.
    For the future don't use mark one concrete containment in an earthquake zone.
    obvious really.

    Dee Cee
     
  16. Dinosaur Rational Skeptic Valued Senior Member

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    Chernobyl was a poorly handled reactor. 20-30 years earlier, A British reactor with the same design had an incident which was minor due to safety precautions in effect from day 1. Some radioactive material escaped, but not enough to be seriously harmful.

    The British experience resulted in Western Technologies building no more reactors using that design, even though the risks were not serious.

    The Russians had few, if any, safety precautions in effect & ignored the knowledge gained by the British incident (assuming they even bothered to pay attention to what the Western World was doing).

    It seems obvious that extra precautions should be put into place for reactors in the Ring of Fire. I am amazed that the Japanese did not consider the possibility of earth quakes & tsunamis when designing their nuclear power plants.

    I am surprised that there are nuclear power plants in California, but maybe they are not near known faults.

    BTW: News media local to me are exaggerating the effects of the Japanese nuclear problems. While it is a financial disaster, it is not disaster level in terms of human health. Americans are hysterical over nuclear power, which has kept us from making full use of it. Politicians pay attention to hysteria because they risk losing the next election if they ignore it. A fictional politician (Asimov Novel) said.
    If I propose & work in favor of that legislation, I will lose the next election in 6 months.If I lose that election, I do not care if the sun goes nova & destroys the Earth in 10 years.​
    Asimov had a clear picture of the mind set of politicians: Give in to idiot voters instead of trying to educate them.

    France gets about 75% of its power from nuclear plants, & has had no problems that I have heard about.

    Fast breeder reactors can be designed to be safe, but there are political objections due to the possibility of using them to make nuclear weapons. Fast Breeders have less problem with disposal of the radioactive byproducts because the final byproducts are much less radioactive than byproducts from other designs.
     
  17. chimpkin C'mon, get happy! Registered Senior Member

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    Regular concrete does something called "spall" at somewhere around 2000 degrees Fahrenheit (1093.33 C): The air bubbles in it start exploding and it begins flaking into pieces.

    At 6,152 degrees Fahrenheit, I suspect the correct term really is just "melt."
    The boiling point of calcium is 1484 c (http://chemistry.about.com/od/elementfacts/a/calcium.htm) and cement is made of crushed limestone primarily, right?

    So, yes, I'm guessing it will boil the cement.
    I believe the core will pretty much melt everything it comes in contact with at that temperature.
     
  18. jmpet Valued Senior Member

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    We do not have enough information to properly assess the situation in Japan. I know what when Chernobyl blew up it literally blew up... that weeks later they found exposed fuel rods on the roof of the building. I know they had an army of people willing to kick those fuel rods down towards ground level- 45 seconds exposure and you're baked. Thousands died and it was all covered up.

    So I would caution to say some drastic measure may need to be taken to control the problem, however widespread it may be. This may possibly mean "volunteers" to expose themselves to a lifetimes-worth of radiation just to get one ounce of it under control.

    I would call in all the experts and have a no BS meeting about options. Then take the best one and make it happen within 72 hours, may God help us. And do it.

    Someone suggested compensation for those brave few who are willing to do what's neccesary and I am all for it. $1 million for one minute in the hot room.

    Sorry to sound so dismal but when news comes in as a trickle, it's mostly because they're covering the rest of it which will come out later.
     
  19. domesticated om Interplanetary homesteader Valued Senior Member

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    can someone explain to me what exactly 'radioactive material' is composed' of and what in particular is the reactor in Japan leaking?

    All the news outlets keep going on about "residents in that part of japan are being exposed to radiation". I was under the impression that harmful levels of radioactivity was a property of specific substances (example - cesium-137).....so wouldn't the news reports need to say "Japanese reactor has been leaking ________" instead?
     
  20. cosmictraveler Be kind to yourself always. Valued Senior Member

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    Please read this , I think it will explain everything that you are asking about.

    http://www.google.com/url?sa=t&sour...t8HbCA&usg=AFQjCNEJgUH_hlD4cGWMD5NdDsuhn3hqLA
     
  21. leopold Valued Senior Member

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    according to the videos i've watched on youtube these reactors had 3 backup systems.
    they all failed.

    what is needed is a redesign of the reactors.
    a good possibility would be to build them in the ocean. this would allow the reactors to fail safe instead of failing critical.
     
  22. joepistole Deacon Blues Valued Senior Member

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    It is my understanding that the nuclear facilities withstood the earthquake with minor damage. However, the subsequent flood wiped out the Diesel engine that powered the backup power supply.

    When the earthquake occured the nuclear reactors shut down as programmed, ceasing electrical production. That left the facility without power except for battery power and the diesel powered generator. The tsunami wiped out the diesel generator so that left only battery power with a very limited life as they were never intended for prolonged useage.

    The design fault here as far as I can see was the heavy reliance on active systems. If designers has relied more on passive systems (e.g. gravity fed cooling as another poster mentioned but you don't have to put it in the sea for that), they possibly could have avoided this nighmare.

    Additionally the problem was compounded by the practice of storing spent fuel rods on site. I understand this is a common practice, because no one wants them stored in their backyard.

    Spent fuel rods must be kept cool just like any other nuclear fuel rod. And if my understanding is correct, it sounds like the spent fuel rods may be the largest hazzard on site.
     
  23. adoucette Caca Occurs Valued Senior Member

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    From what I understand the backup generators weren't particularly damaged, but their fuel tanks floated away.

    They are pumping cooling water into the reactors, and they seem to be doing ok.

    No chance of a meltdown anymore.
    No underground cooling systems, none are needed.

    No.
    There has been no ejection of heavy radioactive elements into the atmosphere.

    A meltdown does not equal an explosion or ejection of material.
    The reactors can no longer melt down, their internal temps are too low.

    None have suffered a meltdown and none will.

    Status as of 11:35 3/17 EST from various official news sources:

    Reactor 1’s primary containment is believed to be intact and the reactor is in a stable condition. Seawater injection into the reactor is continuing.

    Reactor 2 is in stable condition with seawater injection continuing. The reactor’s primary containment may not have been breached, Tokyo Electric Power Co. and World Association of Nuclear Operators officials said on Thursday.

    Reactor 3 is in stable condition with seawater injection continuing. The primary containment is believed to be intact. Pressure in the containment has fluctuated due to venting of the reactor containment structure.

    Workers at the plant continue efforts to add cooling water to fuel pools at reactors 3 and 4. (TEPCO officials say that although one side of the concrete wall of the fuel pool structure has collapsed, the steel liner of the pool remains intact, based on aerial photos of the reactor taken on March 17).

    Reactors 5 and 6 were both shut down at the time the quake occurred. Primary and secondary containments are intact at both reactors.

    Temperature instruments in the spent fuel pools at reactors 5 and 6 are operational, and temperatures are being maintained at about 62 degrees Celsius.

    TEPCO is continuing efforts to restore power at the site. Access problems at the site have delayed connection of a temporary cable to restore off-site electricity, but that is expected later today. The connection will provide power to the control rod drive pump, instrumentation, batteries and the control room.

    One of the emergency diesel units is now in operation and will be used to supply unit 5 and 6 alternately to inject water to their used fuel pools. Later, the power will be used to top up water in the reactor vessels.

    Arthur
     
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