China Syndrome in Japan?

Yeah it looks like it's starting to get more serious. Here's the latest report from out local news :

 

There's no power. How could they turn on their air conditioners?

 

Surely there must be a nuclear expert or knowledgeable person on this forum who could explain simply what is happening to the plant and what could happen.

Obviously the core doesn't melt right through to the other side of the world but how deep does it go? Does it keep on working its way deep into the earth? Would this cause it to explode?

 

FYI,
Following is a copy of my post.
-----
JP government spokesman announced it was hydrogen explosion made from leaked steam.
The explosion occurred out of the reactor container within the building.
The reactor container itself has no damage, and the radiation level is not increased since then.

Keep in touch for further announcement.

Ken@Japan

 

A lot they aren't saying because I'm pretty sure at this point a lot they don't know. When in doubt just evacuate seems to be a prudent measure and one they're taking.

 

The explosion was from a pump, not the nuclear reactor. There have been many explosions following the earthquake, so this is not unusual. Look at all of the burning building for a good example.

The collapsed roof is not related to the explosion. It is the roof of the containment building, not the the containment vessel. The containment vessel is the hardened structure which actually houses the reactor. The containment building is just a normal building around the containment vessel. It serves only to protect the equipment and workers from weather and is in no way related to containing the nuclear material.

The release of some nuclear material, which was referred to above as a "stuck valve", is in fact a pressure release which vents excess pressure from inside of the containment vessel. Excess heat creates steam, and this pressurizes the reactor. The amount of release radiation is minimal.

Normally, when a reactor is shut down, control rods slide down into the reactor and slow the reaction to a very low level. In this essentially powered-off state there is very little heat generation, so little cooling is required. What we don't know, since our news services supply very little real news, is how the reactor was shut down. If the rods are in place it shouldn't be a big deal. If not, there will be scrambling to keep things cool and get the reaction moderated.

Tom

 

"ïf the rods are in place it shouldn't be a big deal. If not, there will be scrambling to keep things cool and get the reaction moderated."

so it seems that things heat up to keep it cool.

 

You can get live streaming using the iPhone app NHK World TV Live for live videos and latest updates not shown here.

 

After the main power producing chain reaction is shut down, there is still considerable thermal power from short life decay products. The emergency cooling system needs to run for several weeks.

SciAm (How to Cool a Nuclear Reactor) doesn't have much content yet, but NPR (Explosion at Japanese nuclear plant) has a running blog.

The Wikipedia page for this plant is [ame="http://en.wikipedia.org/wiki/Fukushima_I_Nuclear_Power_Plant"]Fukushima I Nuclear Power Plant[/ame], and is changing rapidly. This is a very old plant, and was apparently within a couple weeks of planned retirement.

 

It doesn't look good...

 

Another source claims that this incident is currently a 4 on the [ame="http://en.wikipedia.org/wiki/International_Nuclear_Event_Scale"]International Nuclear Event Scale[/ame].

For comparison, Chernobyl topped the scale at 7, and another Soviet disaster was the only 6. Three Mile Island was a 5, as were Windscale, Chalk River, and the Brazilian scavenging incident of a medical cesium radiation source. The link above lists numerous other 4s.

 

Here's a recent article saying the evacuation circle has been expanded to 20km. The metal containment shield is still in place, but pressure is building, and the reactor is not being sufficiently cooled. Not to be an alarmist, but the worst case scenario involves explosion of radioactive material, and radiation blowing across the Pacific.

 

I wouldn't worry about it, unless you live on the west coast.



Tom

 

This looks pretty bad. The plants are Boiling water reactors. This means that when they lose cooling, it's because they have lost water altogether. The explosion was from hydrogen coming from the core....and it looks like a lot of hydrogen was generated and exploded. The mentioning of "seawater" being used for cooling sounds like fire pumps spraying water onto or into the vessel. That has to be a really bad situation.

 

The second reactor is now partially melting down.
The rest are increasing in pressure and requires release of radioactive steam....

Not looking good.

 

Whoops.The global warming doomers plan is to replace fossil fuel with nuke plants.
Just a dumb plan.

 

If they are replacing them with the WRONG KIND OF NUCLEAR PLANT then I would agree...


Thorium based nuclear generation plants are a viable alternative... and safer.

 

:drum: