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Japan Pictures Likely Show Melted Fukushima Fuel for First Time

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Re: Japan Pictures Likely Show Melted Fukushima Fuel for First Time

#81

Post by nate_meurer »

marze wrote: post #6

I still don't see why they are spending years trying to make rad hard robots. A long steel tube with fiber optics to pipe in light, mirrors and optics to transmit an image down the tube would be infinitely easier. They'd need to burn a few holes, but none of the reactor vessels are intact so that wouldn't allow additional radioactive material to escape. I'm surprised the Japanese decision to dump the all the tritium…

Honest question: do you really think they haven't thought of this? You think that none of these engineers and scientists have yet thought of your shielded fiber optics idea? I'm not trying to be mean, I'm really curious.

Radiation shielding is a hard problem. For meaningful reduction of xray and gamma radiation in this environment, we're talking inches of lead cladding [0]. And even that won't ensure a useful lifespan for your fiber, exposed to at least tens of Sv/h along much of its length. And cladding doesn't even begin to address the problem posed by neutron radiation.

The environment in Reactor 2 isn't just hostile to life; it's hostile to organized matter.

http://www.eichrom.com/PDF/gamma-ray-attenuation-white-paper...

Re: Japan Pictures Likely Show Melted Fukushima Fuel for First Time

#82

Post by planteen »

eternauta3k wrote: post #42
QAPereo wrote: post #19

Earlier quoted context omitted.

>A long steel tube with fiber optics to pipe in light, mirrors and optics to transmit an image down the tube would be infinitely easier. That seems likely to degrade the fiber, or the signal and I'm having trouble thinking of any tested fiber in the range of a molten reactor core. The flux is really crazy near that thing, and not just photons, but relativistic electrons and some very angry helium nuclei.

> That seems likely to degrade the fiber, or the signal Could you go into more detail?

Glass darkens from radiation exposure. Even UV does it, Coke bottles at old high altitude mines in Colorado turn a purple color.

Re: Japan Pictures Likely Show Melted Fukushima Fuel for First Time

#83

Post by kijin »

atomwaffel wrote: post #18
kijin wrote: post #9

Earlier quoted context omitted.

Melted Fukushima fuel photographed for the first time. First photos of melted Fukushima fuel. If you take away the tentativeness of "may", "likely", etc., you can make the sentence much easier to read. I wouldn't mind a slight lack of qualifiers as long as the whole thing is not too linkbaity and the content puts the qualifiers back where they belong.

Good point, those are definitely easier to read, although in this age of clickbait I give them credit for admitting a degree of uncertainty right in the headline.

Melted Fukushima fuel likely photographed for the first time :)

Re: Japan Pictures Likely Show Melted Fukushima Fuel for First Time

#84

Post by madaxe_again »

mikeash wrote: post #64
Boothroid wrote: post #43

A common response from defenders of nuclear when concerns are raised is to point to the impact of other energy sources, and say that nuclear is better in those terms. But I just cannot get away from the thought that whilst in aggregate those other forms of energy (fossil fuels, etc) might be provably worse than well managed nuclear within a particular analysis, humanity does not seem capable of this good management o…

The only reason fossil fuels don't have the same potential to go spectacularly bad is because humans don't consider enormous damage to be "spectacular" when it's spread out. Consider: coal alone kills about a million people a year. If those were all concentrated in a small area, we'd call it the greatest disaster the world has ever seen. But it's spread out over the whole world, so we just shrug our shoulders and say…

Furthermore, coal releases more radiation into the environment than nuclear power.

https://www.scientificamerican.com/article/coal-ash-is-more-...

Re: Japan Pictures Likely Show Melted Fukushima Fuel for First Time

#85

Post by afterburner »

"Decommissioning the reactors will cost 8 trillion yen ($72 billion), according to an estimate in December from the Ministry of Economy, Trade and Industry. Removing the fuel is one of the most important steps in a cleanup that may take as long as 40 years."

Hmm, pricey.

Re: Japan Pictures Likely Show Melted Fukushima Fuel for First Time

#86

Post by mikeash »

colordrops wrote: post #76
mikeash wrote: post #64

Earlier quoted context omitted.

The only reason fossil fuels don't have the same potential to go spectacularly bad is because humans don't consider enormous damage to be "spectacular" when it's spread out. Consider: coal alone kills about a million people a year. If those were all concentrated in a small area, we'd call it the greatest disaster the world has ever seen. But it's spread out over the whole world, so we just shrug our shoulders and say…

Why only compare it with fossils fuels?

Because that's what the parent comment did. Obviously a full analysis should include all forms of power generation, but that comment compared fossil favorably to nuclear on the basis that its failures aren't so spectacular.

Re: Japan Pictures Likely Show Melted Fukushima Fuel for First Time

#87

Post by madaxe_again »

colordrops wrote: post #67
mikeash wrote: post #64

Earlier quoted context omitted.

The only reason fossil fuels don't have the same potential to go spectacularly bad is because humans don't consider enormous damage to be "spectacular" when it's spread out. Consider: coal alone kills about a million people a year. If those were all concentrated in a small area, we'd call it the greatest disaster the world has ever seen. But it's spread out over the whole world, so we just shrug our shoulders and say…

When a coal plant fails, it just turns off. When a nuclear plant fails, you've got to get the best people on Earth and tens of billions to contain (not fix) the problem, in one of the most advanced nations on Earth. It made a huge mess that spread to Europe when Chernobyl failed. If nuclear is wide spread, what happens when human incompetence causes a plant failure in a place like Nigeria or Venezuela? Edit: also, I…

You're forgetting about coal mining, which is one of the most life expectancy reducing occupations there is.

Furthermore, coal plants can and do explode - aerosolised coal dust goes with a bang.

https://en.m.wikipedia.org/wiki/Energy_accidents

Re: Japan Pictures Likely Show Melted Fukushima Fuel for First Time

#88

Post by nether »

marze wrote: post #6

I still don't see why they are spending years trying to make rad hard robots. A long steel tube with fiber optics to pipe in light, mirrors and optics to transmit an image down the tube would be infinitely easier. They'd need to burn a few holes, but none of the reactor vessels are intact so that wouldn't allow additional radioactive material to escape. I'm surprised the Japanese decision to dump the all the tritium…

You know, NASA didn't actually spend all that money developing the space pen.

Re: Japan Pictures Likely Show Melted Fukushima Fuel for First Time

#89

Post by [deleted] »

marze wrote: post #6

I still don't see why they are spending years trying to make rad hard robots. A long steel tube with fiber optics to pipe in light, mirrors and optics to transmit an image down the tube would be infinitely easier. They'd need to burn a few holes, but none of the reactor vessels are intact so that wouldn't allow additional radioactive material to escape. I'm surprised the Japanese decision to dump the all the tritium…

[deleted]

Re: Japan Pictures Likely Show Melted Fukushima Fuel for First Time

#90

Post by erikpukinskis »

frivoal wrote: post #30
agumonkey wrote: post #25

Earlier quoted context omitted.

There was a documentary about Tchernobyl surrounding forest few years ago. Most of the vegetation grew back, healthily for my naked eye. Anyways, the most surprising part is that mammals were back too; even though the radiation level was higher than average. I concluded that only a few generation of darwinian selection is needed to breed radiation hardened humans.

Alternatively, the animals aren't radiation hardened and do die of cancer, but not fast enough to get in the way of breeding and multiplying. Or, in other words, while radioactive waste is unhealthy, it fatality rate is lower than having humans around.

... which is why nuclear holocaust is a risk for individuals and nations but not an extinction risk for the species as a whole.
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