Fukushima nuclear plant explosion

[Winston001]

Shag. On TV there is footage of one of the reactors exploding. It looks like the containment building has been breached which means radioactive dust is being released into the local environment.

Its like Chernobyl but with live coverage.

Sky channel 96

[Mom]

Oh dear GOD! Too much! Those poor people.

[Smokin]

Bloody hell, Could it get any worse for the poor buggers.

[mashman]

We just got back from the rugby and saw it... did you see the arced shockwave bursting upwards... looked like a very violent explosion. Just when you thought it couldn't get any worse, poor buggas

[Winston001]

My guess is the containment building has been breached from the build-up of water pressure around the reactor. That has resulted in radioactive dust and smoke being released into the environment.

The problem with this reactor is that the electrical pumps failed after the earthquake despite backups, so the flow of cooling water around the reactor stopped flowing. The reactor automatically shut-down but that doesn't stop or release the heat already in the pile.

There are positives: only one of four reactors at Fukushima has failed. Japanese authorities have been evacuating people over the past 24 hours. The danger is from radioactive dust, not from any sort of atomic bomb explosion. Its possible there won't be a melt-down of the core which can still be cooled if the engineers can get water flowing. Damned dangerous work though.

[EJK]

Fucking hell...

[Crasherfromwayback]

So all of the fuckheads that were/are against wind turbines because they're an eyesore...what would you rather have?

[Winston001]

So all of the fuckheads that were/are against wind turbines because they're an eyesore...what would you rather have?

Umm...actually counter-intuitive as it must seem, I'm still in favour of nulear power. This Fukushima reactor is a 40 year old Westinghouse which is known as old and a bad design. It has had safety features added but clearly they were defeated by this massive earthquake.

The new reactors are far better designed. Japan has a lot of reactors and this is the only one which has failed. Provided the public are evacuated - which has been going on for 24 hours - they are safe.

[mashman]

I thought a shutdown caused the nuclear material to be removed from the fusion chamber? Is this the bit that failed?

[Winston001]

Update - wind is blowing east from Fukushima out to sea. That is the prevailing wind direction and the reason Japanese nuclear plants are built on the east coasts of Japan. So hopefully most of the radioactive dust and steam will blow away to sea.

[Ocean1]

I thought a shutdown caused the nuclear material to be removed from the fusion chamber? Is this the bit that failed?

No, the reaction stopped automatically when the quake hit, the latent heat in the surounding mass is still there, though.

What failed was the cooling system, and it's backup. The third tier backup was designed to last for just a few hours, enough to buy time and to minimise damage in any subsequent containment breach.

[Crasherfromwayback]

Umm...actually counter-intuitive as it must seem, I'm still in favour of nulear power. This Fukushima reactor is a 40 year old Westinghouse which is known as old and a bad design. It has had safety features added but clearly they were defeated by this massive earthquake.

The new reactors are far better designed. Japan has a lot of reactors and this is the only one which has failed. Provided the public are evacuated - which has been going on for 24 hours - they are safe.

Shit hot!

My self personally...I'd rather try and dodge spinning blades than radioactive fallout after /during a big shake. Either way...best wishes to Japan. Mega bad buzz.

[mashman]

No, the reaction stopped automatically when the quake hit, the latent heat in the surounding mass is still there, though.

What failed was the cooling system, and it's backup. The third tier backup was designed to last for just a few hours, enough to buy time and to minimise damage in any subsequent containment breach.

so the coolant heated, turned to steam and blew the place apart?

[Mental Trousers]

That was a hell of an explosion.

There's enough heat in a scrammed reactor to split water into hydrogen and oxygen. If they recombine, that's a hell of an explosion.

When an emergency shutdown of a reactor takes place the graphite control rods or whatever they're using drop into place. The nuclear material doesn't go anywhere, it stays where it is until it's used up. The control rods soak up all the stray protons etc (ie the beta radiation) and that stops the reactor from starting a chain reaction. The damn thing is still friggin hot though so the cooling systems need to be running to get rid of the heat, otherwise it just gets hotter and hotter until things start to melt. Then bad shit happens.

[Winston001]

so the coolant heated, turned to steam and blew the place apart?

Yes. Not quite that straight-forward but essentially right.

The reactor core is a sealed system running water or liquid sodium around the radioactive centre. Outside that is the containment vessel which has low-pressure flowing water which picks up the heat from the sealed system. It is essential for this water to keep flowing because it removes heat (it turns into steam) and drives a generator. It keeps the reactor sealed system cool and safe.

Outside all of that is the containment building which is supposed to keep any steam leaks in.