7 ms·

High radiation readings at Fukushima’s No. 2 reactor complicate robot probe

79 points by sinalc0 10y ago

mikemike5000 10y ago
So, what's the long game with Fukushima? This has been going on for so long and it's concerning that seemingly very little progress has been made. Edit: added "seemingly"... as I can say for certain the degree of progress that has been made.
- sudosushi 10y ago
  It's always been a multi-decade cleanup project, but recently the estimates were pushed further into the future (~40 years). Also, the last article I'd read puts it at ~$180 billion. I can easily see that double before the end.
  - colordrops 10y ago
    Is there a breakdown of the costs of the cleanup?
- gozur88 10y ago
  Every day they let it cool the job gets a little easier, so they're in no particular hurry.
- Animats 10y ago
  Decommissioning a damaged reactor is insanely expensive and, in too many cases, not possible. Chernobyl is at best contained, not cleaned up. 30 years after the fire and meltdown, the giant curved roof built to cover it was moved into position last year. That will hold things for a few more decades. The next generation will have to work out the next steps. The jammed AVR pebble bed reactor in Germany is contained, but there's no way to dismantle and dispose of it. Current plans are to wait 60 years and then try to figure out something. Fukushima’s mess will also take decades. The site generated huge amounts of contaminated water, and there's now a processing plant to take most radioactive contaminants out of the water. The water still has tritium after processing. The half-life of tritium is 12 years, so that will cool off in a few decades. Meanwhile, huge farms of water tanks store the stuff. Lots of radioactive dirt has been dug up and buried deeper somewhere else. There's a refrigerated "ice wall" to try to stop leakage into the ocean. Not much has been done with the reactor vessels themselves. As today's story reports, they can't even get a robot close to the reactor vessel. This makes one very discouraged about nuclear power.
  - pinpelipon 10y ago
    Tritium & tritiated water can be somewhat easily separated from water. Just freeze the mixture, and it forms layers. However, there probably is quite a bit of tritiated water.
    - Animats 10y ago
      However, there probably is quite a bit of tritiated water. Yes. Here's the tank farm.[1] It could probably be let out into the ocean without much harm, if not done all at once. But there's opposition to that. Meanwhile, it decays with a half-life of 12 years, so eventually it will be harmless. Frustratingly, the concentration of tritium is too low for commercial extraction. [1] http://atomicinsights.com/wp-content/uploads/fukushimatanks_sm.jpg http://atomicinsights.com/wp-content/uploads/fukushimatanks_...
  - codecamper 10y ago
    Solar panels folks. Solar panels. Wind. Batteries. We can do it, no problem. Electricity costs a little more, but your car ends up costing less. Less maintenance on fewer parts - just swap out the battery which declines in cost each year. Keep fossil fuels and wood for the things solar & wind will have trouble covering: airplanes, ocean shipping, winter heating.
    - tptacek 10y ago
      We cannot do it: https://www.youtube.com/watch?v=9yNj1zEh-nM https://www.youtube.com/watch?v=9yNj1zEh-nM You only need the first 15 minutes of this talk to see why current renewables won't scale. The world needs something like 15 terawatts. When this talk was recorded, solar electricity produced something like .001 TW. We're now closing in on .03 --- and there are huge parts of the world that still haven't industrialized yet. We'd apparently need to be printing and distributing and deploying solar cells the way we do newspapers to have any hope of using photovoltaic to offset our total energy demand. Nuclear doesn't scale either, but the notion that we're all just holding back on renewables out of greed because all it takes is wind and solar... well, it's easily refuted.
- coldtea 10y ago
  >So, what's the long game with Fukushima? This has been going on for so long and it's concerning that seemingly very little progress has been made. Long? They are still, to this day, trying to bury and isolate Chernobyl's reactors.
static_noise 10y ago
Somehow it seems strange that Japan, the motherland of robots, fails to build a robot. Money can't be the reason. There has been an investment surge into radioactive cleanup technology starting with the damaged reactors six years ago. Six years and billions of dollars later we get a robot that gets stuck and fails after just two hours. From what I've gathered they didn't even include a proper radiation sensor but used the camera noise in order to "guesstimate" the dosage after the fact. Did they not expect high radiation in that location?
- Pica_soO 10y ago
  Electronics of the shelve get very unreliable in high dosage environments. The radiation rewrites your loaded programs, by flipping bits and causing rising edges where there shouldn't be some. So the program running on your camera will dissolve above some radiation levels, locking it in a watchdog detects and reboot cycle. There are approaches to circumvent that in low to medium environment- one is to have redundant systems and select the "majority" vote on computation results. But at this level, the only solution is to not have computation near the source and put up with long cable/fibre cable delay- which is tough with complex sensors (aka computers) like cameras. It is probably some snail-eye setup- the camera a remote mini-drone on cable, retracted on black out.
  - static_noise 10y ago
    Does that mean you cannot use robots, nor can you use humans, to clean up this mess? What do you do then?
    - Pica_soO 10y ago
      It means, that the robots have to be very "custom" build ones. With the intelligent parts beeing deposited outside of the dangerous area, communicating with the muscle via e.g. fibreoptics. The robot consists ideally of some die-hard sensors positioned as far away as possible and as close as necessary - which are retractable mechanically in case of software failure by left behind elements. Then there is the actual tooling, which is basically just a remote controlled shell. A complicated setup, to say the least. Imagine a Anemone with some little remote camera fishes on a tentacle, controlling a robotic crab on the longest tentacle of them all.
codecamper 10y ago
Could a future earthquake jolt the reactor back into danger mode?
- u_wot_m8 10y ago
  It's still in danger mode, still leaking massive amounts of radiation into the pacific ocean. Based on what I've read of dying ocean life it's probably one of the worst environmental disasters in history
  - dabeeeenster 10y ago
    Do you have a source?
  - e40 10y ago
    Not according to the recent Nova I watched on the subject.
  - tptacek 10y ago
    Reprising: There are 187000000000000 million gallons of water in the Pacific Ocean, meaning that "radioactive waste" is 2.1 x 10^-10% of the body of water itself. The waste takes the form of HTO, tritiated water, which has extremely low bioavailability and has already been introduced in abundance to the ocean by other events. There are things to be alarmed about, but this isn't one of them.
choonway 10y ago
Are there any startup robotic companies that are doing robots that can deal with hard radiation? It seems that they are trying to wash off some melted gunk that is blocking their way into the area beneath the vessel where the core is suspected to be. Will building a robot capable of completing such a task under such an environment attract any funding? Anywhere to apply?
- dottedmag 10y ago
  One can arguably find the engineers who created robots used in Chernobyl, which were oblivious to radiation by using pneumatic tubing for control.
coldtea 10y ago
And radiation readings were massive (even compared to something like Chernobyl) the last months. Funny how the pro-nuclear trolls took whatever official BS was out about Fukushima ("nothing to worry about") line, hook and sinker. As if doubting technology (the application of science by humans, including incompetent bureaucracies, greedy corporations and non-perfect designers) is the same as doubting science.
amelius 10y ago
I'm wondering, can't they use the radiation as an alternative to light (photons), in that environment? I'm guessing the radiation would scatter in a way comparable to light, so you would be able to get a similar kind of "imaging". Not sure how one would implement a radiation detector in silicon, but at least you could shield it by some layer of metal to get out of the range of overload and into the range of sensitivity.
- the8472 10y ago
  High energy photons are quite different compared to visible light. They scatter instead of being reflected. They have a low cross-section which means you can't make tiny pixels. No reflection or diffraction means no optics.

79 points by sinalc0 10y ago

So, what's the long game with Fukushima? This has been going on for so long and it's concerning that seemingly very little progress has been made. Edit: added "seemingly"... as I can say for certain the degree of progress that has been made.

sudosushi 10y ago
It's always been a multi-decade cleanup project, but recently the estimates were pushed further into the future (~40 years). Also, the last article I'd read puts it at ~$180 billion. I can easily see that double before the end.
- colordrops 10y ago
  Is there a breakdown of the costs of the cleanup?
gozur88 10y ago
Every day they let it cool the job gets a little easier, so they're in no particular hurry.
Animats 10y ago
Decommissioning a damaged reactor is insanely expensive and, in too many cases, not possible. Chernobyl is at best contained, not cleaned up. 30 years after the fire and meltdown, the giant curved roof built to cover it was moved into position last year. That will hold things for a few more decades. The next generation will have to work out the next steps. The jammed AVR pebble bed reactor in Germany is contained, but there's no way to dismantle and dispose of it. Current plans are to wait 60 years and then try to figure out something. Fukushima’s mess will also take decades. The site generated huge amounts of contaminated water, and there's now a processing plant to take most radioactive contaminants out of the water. The water still has tritium after processing. The half-life of tritium is 12 years, so that will cool off in a few decades. Meanwhile, huge farms of water tanks store the stuff. Lots of radioactive dirt has been dug up and buried deeper somewhere else. There's a refrigerated "ice wall" to try to stop leakage into the ocean. Not much has been done with the reactor vessels themselves. As today's story reports, they can't even get a robot close to the reactor vessel. This makes one very discouraged about nuclear power.
- pinpelipon 10y ago
  Tritium & tritiated water can be somewhat easily separated from water. Just freeze the mixture, and it forms layers. However, there probably is quite a bit of tritiated water.
  - Animats 10y ago
    However, there probably is quite a bit of tritiated water. Yes. Here's the tank farm.[1] It could probably be let out into the ocean without much harm, if not done all at once. But there's opposition to that. Meanwhile, it decays with a half-life of 12 years, so eventually it will be harmless. Frustratingly, the concentration of tritium is too low for commercial extraction. [1] http://atomicinsights.com/wp-content/uploads/fukushimatanks_sm.jpg http://atomicinsights.com/wp-content/uploads/fukushimatanks_...
- codecamper 10y ago
  Solar panels folks. Solar panels. Wind. Batteries. We can do it, no problem. Electricity costs a little more, but your car ends up costing less. Less maintenance on fewer parts - just swap out the battery which declines in cost each year. Keep fossil fuels and wood for the things solar & wind will have trouble covering: airplanes, ocean shipping, winter heating.
  - tptacek 10y ago
    We cannot do it: https://www.youtube.com/watch?v=9yNj1zEh-nM https://www.youtube.com/watch?v=9yNj1zEh-nM You only need the first 15 minutes of this talk to see why current renewables won't scale. The world needs something like 15 terawatts. When this talk was recorded, solar electricity produced something like .001 TW. We're now closing in on .03 --- and there are huge parts of the world that still haven't industrialized yet. We'd apparently need to be printing and distributing and deploying solar cells the way we do newspapers to have any hope of using photovoltaic to offset our total energy demand. Nuclear doesn't scale either, but the notion that we're all just holding back on renewables out of greed because all it takes is wind and solar... well, it's easily refuted.
coldtea 10y ago
>So, what's the long game with Fukushima? This has been going on for so long and it's concerning that seemingly very little progress has been made. Long? They are still, to this day, trying to bury and isolate Chernobyl's reactors.

static_noise 10y ago

Somehow it seems strange that Japan, the motherland of robots, fails to build a robot. Money can't be the reason. There has been an investment surge into radioactive cleanup technology starting with the damaged reactors six years ago. Six years and billions of dollars later we get a robot that gets stuck and fails after just two hours. From what I've gathered they didn't even include a proper radiation sensor but used the camera noise in order to "guesstimate" the dosage after the fact. Did they not expect high radiation in that location?

Pica_soO 10y ago
Electronics of the shelve get very unreliable in high dosage environments. The radiation rewrites your loaded programs, by flipping bits and causing rising edges where there shouldn't be some. So the program running on your camera will dissolve above some radiation levels, locking it in a watchdog detects and reboot cycle. There are approaches to circumvent that in low to medium environment- one is to have redundant systems and select the "majority" vote on computation results. But at this level, the only solution is to not have computation near the source and put up with long cable/fibre cable delay- which is tough with complex sensors (aka computers) like cameras. It is probably some snail-eye setup- the camera a remote mini-drone on cable, retracted on black out.
- static_noise 10y ago
  Does that mean you cannot use robots, nor can you use humans, to clean up this mess? What do you do then?
  - Pica_soO 10y ago
    It means, that the robots have to be very "custom" build ones. With the intelligent parts beeing deposited outside of the dangerous area, communicating with the muscle via e.g. fibreoptics. The robot consists ideally of some die-hard sensors positioned as far away as possible and as close as necessary - which are retractable mechanically in case of software failure by left behind elements. Then there is the actual tooling, which is basically just a remote controlled shell. A complicated setup, to say the least. Imagine a Anemone with some little remote camera fishes on a tentacle, controlling a robotic crab on the longest tentacle of them all.

codecamper 10y ago

Could a future earthquake jolt the reactor back into danger mode?

u_wot_m8 10y ago
It's still in danger mode, still leaking massive amounts of radiation into the pacific ocean. Based on what I've read of dying ocean life it's probably one of the worst environmental disasters in history
- dabeeeenster 10y ago
  Do you have a source?
- e40 10y ago
  Not according to the recent Nova I watched on the subject.
- tptacek 10y ago
  Reprising: There are 187000000000000 million gallons of water in the Pacific Ocean, meaning that "radioactive waste" is 2.1 x 10^-10% of the body of water itself. The waste takes the form of HTO, tritiated water, which has extremely low bioavailability and has already been introduced in abundance to the ocean by other events. There are things to be alarmed about, but this isn't one of them.

choonway 10y ago

Are there any startup robotic companies that are doing robots that can deal with hard radiation? It seems that they are trying to wash off some melted gunk that is blocking their way into the area beneath the vessel where the core is suspected to be. Will building a robot capable of completing such a task under such an environment attract any funding? Anywhere to apply?

dottedmag 10y ago
One can arguably find the engineers who created robots used in Chernobyl, which were oblivious to radiation by using pneumatic tubing for control.

coldtea 10y ago

And radiation readings were massive (even compared to something like Chernobyl) the last months. Funny how the pro-nuclear trolls took whatever official BS was out about Fukushima ("nothing to worry about") line, hook and sinker. As if doubting technology (the application of science by humans, including incompetent bureaucracies, greedy corporations and non-perfect designers) is the same as doubting science.

amelius 10y ago

I'm wondering, can't they use the radiation as an alternative to light (photons), in that environment? I'm guessing the radiation would scatter in a way comparable to light, so you would be able to get a similar kind of "imaging". Not sure how one would implement a radiation detector in silicon, but at least you could shield it by some layer of metal to get out of the range of overload and into the range of sensitivity.

the8472 10y ago
High energy photons are quite different compared to visible light. They scatter instead of being reflected. They have a low cross-section which means you can't make tiny pixels. No reflection or diffraction means no optics.