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Robot Squeezes Suspected Nuclear Fuel Debris in Fukushima Reactor (theverge.com)
A robot outfitted with remotely controlled pinchers poked at debris that's suspected to contain molten nuclear fuel at the bottom of one of Fukushima's nuclear reactors, World Nuclear News reports. From a report: The poking and prodding is part of the ongoing cleanup effort at Japan's Fukushima Daiichi power plant, the site of a major nuclear accident in 2011. The dextrous robot was dangled into the Unit 2 reactor on February 13th, according to a news release from the plant's operator, Tokyo Electric Power Company (TEPCO). Unit 2 is one of the reactors at the Fukushima Daiichi power plant that overheated after a massive earthquake and tsunami hit Japan in 2011, which caused the reactor core to melt. TEPCO suspects that radioactive fuel may have melted through the bottom of the reactor vessel to fall into the containment structure surrounding it. The company has to find the radioactive debris and figure out how to remove them, so TEPCO has been sending in a series of robots to scout out the reactors. It's a dangerous journey that some of the robots haven't survived.
If you're suggesting they can induce criticality by poking debris with a claw, you're dumber than I give you credit for.
Scary.
Poke-e-mon.
Table-ized A.I.
I should hope they're trying to clean this mess up.
....for 1000, Alex.
Palaces, barricades, threats, meet promises
Like, for a fat bum? ..or pincers?
Mr. Whipple will get upset.
Hard to believe this happened 8 YEARS ago. Even more hard to believe is just how little Japan has done to prevent further incidents. Though the wikipedia article is massive and outright redundant propaganda to read, one word you will not find is an arrest... of anyone.
ok, youre there, hows the environment? theres enough radiation down here to cook a chicken guys, can i come back up now? not just yet, see that radioactive material? give it a squeeze ....for real? is that safe? that sounds like its not safe.
sure yeah youre a robot just...give it a quick squeeze
ok, i squeezed it, what now??
wear it like a little hat. little robot hat. ....so but this is for science?
oh uh, yeah all the best robots do it for science
Good people go to bed earlier.
Well, it was (around) St. Valentine's day, even robots need to squeeze something...
Thank you, I will be here all week!
BookDetective.net - book search engine and ranker I donate my skills to.
He probably pays robots to squeeze it too.
The dextrous robot was dangled into the Unit 2 reactor
Maybe if they didn't make their robots out of sugar they would last longer under the heat.
I am armed because I am free. I am free because I am armed.
Nuclear apologists seem pretty quiet in this thread today.
This is a perfect example of why nuclear power is a failure and should not be adopted over renewables.
we've had nuclear power for like 70 years and already had several accidents. Nuclear fuel does not degrade for tens of thousands of years. Its a waste problem far greater than c02, and is just as short sighted as the reliance on fossil fuels. Perhaps moreso.
Real world experience, and human nature, trumps engineers and designers perfect scenarios everytime.
As a potential lottery winner, I totally support tax cuts for the wealthy
Just drop a nuke on it. No further attention needed. Its not like it will be the first time.
Send in the CEO.
The plants failed for 3 reasons. 1, Diesel generators and electrical systems for emergency cooling systems were built below sea level so the tsunami wrecked the engines and the electrical switch gear. Ruined all. 2, off site emergency power was routed thru the same under sea lever switch gear, so no cooling was available. 3, Years before the tsunami, engineers wanted a wall added to keep the emergency cooling stuff dry but management refused due to cost in money and in loss of face.
Emergency cooling is needed due to reactions that continue after the poison rods move to 0 power position. About 6 hours are needed for core power to decay down near normal idle level. When earthquakes or winds wreck power lines, the reactor must be tripped & secondary or emergency cooling systems employed to prevent over temperatures in the pot.
Primary containment of nuclear fuel in use is the reactor pot, a thick steel pressure vessel. Secondary containment is the floor of the reactor building. US plants have over 5 feet of thick rebars and concrete as floor of the reactor building. Japanese? Until the fuel gets thru the floor, it has not escaped. Temperatures and neutron radiation needed to wreck the floor did not exist during the first 2 months after the tsunami, so the floor is intact, the is fuel contained.
Vigorous washing with seawater did propel burned equipment bits up out of the building.
Initial robots failed due to neutron radiation while the fuel decayed. Now the fuel has largely decayed and is not in configuration needed to generate neutrons & high temperatures. So the robot now survives. If the pot was perforated, is was soon after the tsunami. Over, done. Not going to happen now. Comparisons to the Russian plants with fuel surrounded by carbon is foolish. Russians used carbon as moderator, Japan & US use water as moderator. Most often, water does not burn. Comparisons to nuclear bombs is more foolish. 2% nuclear fuel is not capable of nuclear explosions. Over 98% fissionable uranium is needed for bombs. Go read how bombs work, how all must activate fully in sequence for a nuclear explosion. You will not again compare any power plant to such a bomb. Unless you are a troll.
Large 550,000 volt power lines are the only way to transport power interstate. Bow, arrow, sting, rope & wire are all the equipment needed to again down high power lines. Local power generation, local lines & local storage are the only safe way in this country that invites Muslims. Jihad is not compatible with country wide power systems.
with a Uranium fetish!
A report called Nuclear Power Plant Security and Vulnerabilities explored vulnerabilities at nuclear power plants.
From that the issue of spent fuel pool vulnerabilities warranted further study in the now declassified report Safety and Security of Commercial Spent Nuclear Fuel Storage: Public Report by the Committee on the Safety and Security of Commercial Spent Nuclear Fuel Storage within the National Research Council which details variation of the above scenario from a terrorist attack, as opposed to a disaster.
You can find information about plutonium oxidization Evaluation of source-term data for plutonium aerosolization which starts at around 500 centigrade.
Actions to reduce the possibility of these kinds of scenarios are simple and cost effective. Mainly by dry cask storing fuel that has cooled for 5 years and separating and dispersing spent fuel recently removed from the reactor throughout the pool. All very practical, affordable actions for reducing this risk.
Information about the fuel removal process and the damage to the Unit 3 spent fuel pool in Tepco's Fukushima spent fuel removal plan.
There is very little point arguing with people who look at Nuclear power from an idealistic viewpoint. For them Nuclear power is perfect and requires no improvements. This, according to the official report into the Fukushima accident is how it occurred.
Again I would like to express my gratitude to the workers and engineers attempting to get the Fukushima disaster under control.
My ism, it's full of beliefs.
I said "There is a reason that spent fuel rods are kept in a pool with a constant supply of cool water" that is the context. The fuel rods are MOX so we agree that they contain plutonium.
Sure, you could swim in a spent fuel pool, you just wouldn't open your eyes. However I wouldn't hang around if the water drained out or the spent fuel pool collapsed and smashed several thousands tones of concrete and fuel rods together.
Unless you happen to have the manifest for the fuel composition of Fukushima Unit 3 that you can share it's fair to say that you don't know what it is going into the reactor. No one has any idea what the composition of those fuel rods are when they are hot and coming out of the reactor. At issue is there is enough plutonium to start criticality and more than enough energy in the mass of remaining spent fuel for it to become critical within a supercritical radioactive fire outside of a nuclear reactor.
The key take-away for you here is the difference between inside and outside of the body and bio-accumulation in the food chain.
I think you're missing that Fukushima is in the presence of seawater because it's next to the ocean therfore Plutonium *Chloride* is produced which is highly soluble to metabolic processes. Your ignorance lies in that plutonium is an energetic alpha emitter which you refer to as weak because most living things are resistant to external alpha exposure. However it is an energetic alpha so when it is absorbed *into* the body that exposure is *internal* exposure and much more problematic because the layers of skin aren't wrapped around our internal organs.
Plutonium oxide is a potential inhalant and once it is breathed in it is very difficult to remove.
This is the difference between external radiation exposure and internal radiation exposure.
Except we are talking about reactor cores that weigh about 160 tonnes and we have 40 years worth of spent fuel stacked up. So yeah it's many hundreds of tonnes.
I note how emotional you appear and how divorced from reality this makes your rant.
In this sentence several thousand of TONNES with roughly a one kilo warhead would translate to "several thousands" of nuclear warheads when we know there were several hundreds of nuclear tests. That's several hundred kilograms, not several thousand tonnes. Quite a discrepancy in what
My ism, it's full of beliefs.