Major Earthquake & Tsunami in Japan

[GTlondoner]

some one told me its just anti-nuclear protesters trying to make it seem worse than it is,
no need to freak out, You freaking out yet Omnis.

EDIT: [/sarcasm]

 

[Touring Mars]

I think news outlets are trying to be very delicate with this nuclear issue. They don't want entire populations at large to panic. Aka sugar coating

I don't know about that - the BBC are calling it 'a possible meltdown', which doesn't sound much like sugar coating to me They have to stick to the facts and not speculate too much. They don't know the extent or the nature of the radiation leak, but they are showing the same pictures we are seeing elsewhere, and it's pretty obvious that the chances of a serious radiation leak are higher than everyone may have hoped.

While the consequences could be disasterous (not least for the Japanese economy, given Japan's heavy reliance on nuclear power), for the moment it is those who live nearby that need to be concerned and are being evacuated. For the rest of us, however, there's not much we can do about it anyway.

 

[Ken]

I think news outlets are trying to be very delicate with this nuclear issue. They don't want entire populations at large to panic. Aka sugar coating

I would have to agree. They definitely seem to be down playing to me. But I understand the reasoning to some degree. More panic is not what's needed. But on the other hand, that lack of panic could make this disaster much, much worse. Best example of a double edged sword that I can think off.

 

[Big Ron]

some one told me its just anti-nuclear protesters trying to make it seem worse than it is,
no need to freak out, You freaking out yet Omnis.

Come on, man. You could see, how the reactor building exploded. What do you think, happened there? Some anti- nuclear protestor send a photoshoped video or what?

 

[GTlondoner]

Some didn't get my sarcastic poke at Omnis then

page 14 check it out

 

[lbsf1]

Here is an update from bbc news with an interesting story from a member of the public.


0957: From Richard Black, BBC environment correspondent: "Although Japan has a long and largely successful nuclear power programme, officials have been less than honest about some incidents in the past, meaning that official re-assurances are unlikely to convince everyone this time round.


"0951: Lan Murata in Kaneyama writes: "The heater has gone off hours before and now it's freezing. It was the biggest I ever felt. I always thought the earthquake drills were the waste of time at school. But I was wrong, I felt thankfulI that I didn't panic, our family is lucky that we have a drawer full of emergency goods. My mum is one who survived the earthquake in 1995 in Kobe. Some of the boards are loose on the stairs. But I can't move any further because a bookshelf is blocking the stairs." Have Your Say

 

[Nielsen]

It is obviously one of the reactor buildings which blew so it's not unlikely that a meltdown has occured already. This is really bad and I also expect that the news we receive at the moment is delayed compared how serious this is. Danish TV also says that the amount of radiation leaked is very high compared to normal amounts. The radiation doze which normally is given during a year is currently given during one hour around the plant. They also said that they receive reports that people are escaping from Tokyo because of this but the wind direction could help by blowing the cloud towards the Pacific. On top of that they have similar cooling problems at four other reactors in the country. I'm afriad Japan is facing far bigger problems than the Tsunami itself at the moment.

 

[lbsf1]

Another worrying bit of news.

#
1009: "This is starting to look a lot like Chernobyl" Walt Patterson, an associate fellow with Chatham House, has told the BBC after seeing pictures of the explosion at the Fukushima-Daiichi nuclear plant. "The nuclear agency says that they have detected caesium and iodine outside the unit, which certainly indicates fuel melting at the very least," he says. "Once you have melting fuel coming into contact with water, that would almost certainly be the cause of the explosion."

 

[Big Ron]

On my news channel an expert said that explosion could have been caused by explosive gas. Explosive gas is created when the boiling water is split into hydrogen and oxygen by the reactor heat. And it can create huge explosions, too.

 

[Omnis]

some one told me its just anti-nuclear protesters trying to make it seem worse than it is,
no need to freak out, You freaking out yet Omnis.

Come on, man. You could see, how the reactor building exploded. What do you think, happened there? Some anti- nuclear protestor send a photoshoped video or what?

Some didn't get my sarcastic poke at Omnis then

page 14 check it out

Hey, it's OK. Now that I am more informed about what the actual situation is (an explosion is usually helpful in establishing a degree of severity), I can say that perhaps I was wrong.

That really was all I could ascertain at the time. There wasn't much actual information about what is going on until they reported the explosion. There still isn't much information-- we still don't know a lot of things about it, what caused it, what it damaged, and what the consequences for radioactive exposure are.

 

[GTlondoner]

Hey, it's OK. Now that I am more informed about what the actual situation is (an explosion is usually helpful in establishing a degree of severity), I can say that perhaps I was wrong.

That really was all I could ascertain at the time. There wasn't much actual information about what is going on until they reported the explosion. There still isn't much information-- we still don't know a lot of things about it, what caused it, what it damaged, and what the consequences for radioactive exposure are.

Its cool man, to be honest i wish you was right 👍

 

[lbsf1]

Next big update.
The BBC's environment correspondent Roger Harrabin says he understands the blast at the nuclear plant may have been caused by a hydrogen explosion - also one of the possibilities laid out by Walt Patterson of Chatham House. "If nuclear fuel rods overheat and then come into contact with water, this produces a large amount of highly-flammable hydrogen gas which can then ignite," our correspondent says.


And reportedly they have also increased the area evacuated from 10km to 20km from the 2 power plants.

 

[Ken]

Next big update.
And reportedly they have also increased the area evacuated from 10km to 20km from the 2 power plants.

That isn't going to be enough if this goes bad. Not with the water contamination playing with this. This could be definitely be far worse than the Tsunami.

 

[lbsf1]

That isn't going to be enough if this goes bad. Not with the water contamination playing with this. This could be definitely be far worse than the Tsunami.

And also if it was the hydrogen that was the problem then the internal tank which holds the uranium must have been breached.

 

[Nielsen]

Anybody seen any news articles about how people are responding in Tokyo? Danish TV briefly mentioned that people in Tokyo have started escaping in fear of radiation. Sounds really bad to me.

 

[Ken]

And also if it was the hydrogen that was the problem then the internal tank which holds the uranium must have been breached.

Exactly my thoughts. The repercussions that are absolutely unimaginable. Not just presently, but how would it affect the future of the one of the most populous nations on the planet. You have to think that the Tsunami and the power plant explosion and contaminants will affect the world population now. But what is going to happen we learn about the affects this has had on the third largest economy? But at this time, that's neither here or there. The pressing matter is finding survivors, and ensuring the death toll doesn't rise any more. I myself have just made a donation to a fund to help Japan find survivors.

 

[Stevisiov]

It's still unclear whether the explosion has affected the containment of radioactive materials. It certainly is concerning though.

 

[Omnis]

What can we learn from all this? Well, so far: install the back-up generators and engines on the roof of the containment structure.

edit: Here's your problem! http://af.reuters.com/article/energyOilNews/idAFL3E7EC07P20110312

In late 2006, the government ordered TEPCO to check past data after it reported that it had found falsification of coolant water temperatures at its Fukushima Daiichi plant in 1985 and 1988, and that the tweaked data was used in mandatory inspections at the plant, which were completed in October 2005.

 

[Griffith500]

Well, to fully understand what's going on you'd need to be a nuclear engineer and you'd need to be familiar with these particular Boiling Water Reactors (BWR) that are in trouble right now.

Basically, in a nuclear power plant you have fuel rods which undergo nuclear fission. That means that they are comprised of one element and split into smaller elements, and they release a ton of energy in the process. The reaction proceeds until the fuel rod becomes completely spent, meaning there is no more of the original element left to split. These particular reactions require a neutron to initiate, and they give off a few neutrons when they complete. These product neutrons then initiate more and more reactions until you get this uncontrollable chain reaction.

Nuclear power plants impose a restriction to control the chain of reaction. They use control rods next to the fuel rods which soak up a lot of the released neutrons and keep the chain reaction from getting out of hand.

These BWRs use water that gets vaporized by the hot reactor and is then cycled past a turbine to generate electricity, and returned to the reactor after being cooled and re-condensed. The water also acts as the electron moderator instead of control rods. (Maybe they have control rods too, I don't know.) So, basically, when they can't re-condense the water, there are fewer neutrons picked up by the vapor than what the liquid is able to absorb. So those neutrons react with the fuel rods making them get hotter and hotter and making the pressure in the system rise higher and higher until the reactor vessel can no longer hold it.

I guess the fix is, obviously, to get the condensers back up and running, but I think they were also trying to vent the steam and refill with fresh water. The problem with purging the reactor is that all the steam in there is radioactive. That's in addition to the MASSIVE pressure built up in those things. Otherwise, they could just purge it like they do when they quench superconducting magnets.

I've sent a message asking about this to my friend that's a nuclear engineer at Texas A&M. Let's see what he has to say.

This is utter nonsense!

BWRs do not exhibit such thermal runaway, PWRs do since they do not allow boiling soon enough.

The lower pressure and deliberate two-phase design of a BWR allows for an increased void fraction (i.e. fraction of vapour / steam versus water around the fuel rods) which then produces fewer thermal neutrons. That is more neutrons are too fast to interact with the fuel and sustain fission - the water is needed to slow the neutrons down in order to keep the reaction going. BWRs are, therefore, self-regulating.

I cannot believe the BBC has a "related" article linked to the explosion explaining "how nuclear reactors work" and it's the wrong ****ing type! Idiots.


This explosion is likely the containment chamber immediately around the pressure vessel rupturing due to being over-pressure. They had said they'd lost the power to control the pressure in these devices, and there are similar problems at at least two other plants just to the south, but they are of a different containment design.


The Japanese designs all use Nitrogen in their containment systems, so Hydrogen shouldn't form at all (it needs oxygen available to create the metal hydroxide) - Fukushima-Daiichi 1 is the earliest design and definitely uses Nitrogen, whilst later international designs did away with the "need" for it, but the Japanese still use it - this applies to the plants at Fukushima-Daini.

The only way it could have been a hydrogen explosion is if the containment volume was already exposed to the air, which means it had leaked a lot before the explosion. However, the pressure-vessel has been reported as being at a stable pressure, so it's temperature will also be stable (i.e. no greater than 314°C over the normal 285°C, assuming the reported 1.5 times overpressure is accurate.) I'm not sure what temperatures are needed to start the hydroxylation of steel in water... There could be other metals present, of course.

 

[Tesla]

I cannot believe the BBC has a "related" article linked to the explosion explaining "how nuclear reactors work" and it's the wrong ****ing type! Idiots.

Of course. The BBC is well known for its' team of Nuclear Energy experts. Considering the amount of worry and grief that some people are going through right now, they will want as much information as possible in a short space of time. The BBC (and other websites) are doing the best they can to keep up to date with the events.

 

[Omnis]

Yes! Finally someone that knows what they're talking about. I read about it for a while and got the gist of it but I guess I screwed up the part about the vapor/liquid while retelling the story. Thanks for correcting that. That makes perfect sense to me now.

The thing I don't get is what exactly the problem is. What's making the pressure rise so much? Decay heat? Don't you need the water to cool the fuel rods even if the reaction is kept regulated by the moving-too-fast neutrons? I think this has been obfuscated by the news a little bit. They're reporting to people that just want to know whether they're going to live or whether they're going to grow a foot on their forehead and die.

 

[Tesla]

They're reporting to people that just want to know whether they're going to live or whether they're going to grow a foot on their forehead and die.

I LOLed. But, seriously, if you get a reply from

my friend that's a nuclear engineer at Texas A&M

please post.

 

[Griffith500]

Of course. The BBC is well known for its' team of Nuclear Energy experts. Considering the amount of worry and grief that some people are going through right now, they will want as much information as possible in a short space of time. The BBC (and other websites) are doing the best they can to keep up to date with the events.

I'm no expert, but even I can tell the difference between the acronyms "BWR" and "PWR"

 

[Max_DC]

No thanks, we don't need it in our part of the world.

What do you think, where it streams then? Every direction will be a catastrophe.

Every mile of open empty water will reduce the degree of radioactive contamination within this cloud. The ocean can easily deal with it, the amount of radioactive material that eventually reaches the US coast won't be relevant.
So that's my hope.

A few minutes ago I saw a weather expert saying that the next 4-5 days will provide exactly these conditions and hopefully even longer.

Seems like the Kamikaze could save Japan once again...
http://en.wikipedia.org/wiki/Kamikaze_%28typhoon%29

 

[Omnis]

I LOLed. But, seriously, if you get a reply from please post.

I will, but I doubt he can elucidate anything more than what is already public info. And that's not much.

 

[TheDabbinDave]

Here it is 7am on the east coast. This plant explosion is at the top of discussion. They're calling it (potentially) the 2nd worst nuclear disaster in history. Whether or not a meltdown is occurring won't be determined until inspectors get in there.

 

[Griffith500]

1202: Government spokesman says the nuclear reactor container at the Fukushima-Daiichi plant has not been damaged, and the level of radiation has dropped following the explosion earlier on Saturday, AFP reports.

Source.

Bloke on the telly is saying it seems the containment structure (a steel "box" around the reactor) has ruptured, and not the pressure vessel itself (i.e. the reactor "core" - the bit with the fuel in).

 

[G.T.Ace]

It didn't look like a explosion from a meltdown itself, more like what some experts say, melting fuel + water. But the reactor shell was blown up, so there's radioactivity spreading out now.

Keep an eye on the news, wind directions and weather are important now! This could affect everyone of us!

EDIT: I doubt that, the whole thing collapsed.

 

[Griffith500]

It didn't look like a explosion from a meltdown itself, more like what some experts say, melting fuel + water. But the reactor shell was blown up, so there's radioactivity spreading out now.

Keep an eye on the news, wind directions and weather are important now! This could affect everyone of us!

EDIT: I doubt that, the whole thing collapsed.

Steam explosions can be pretty damned energetic. There is no fire, which would be indicative of a hydrogen explosion of any appreciable scale (i.e. that would bring the roof down...). That cube is not the containment (EDIT: not the primary one, anyway) structure. It's a small steel hull within that, inside which sits the reactor.

Pressure in the reactor is now decreasing.

 

[G.T.Ace]

I've already seen some physicists saying "no reactor can survive such a blast".
Looks like they're trying to flood the whole thing now for further cooling.

But like you said, it looks like a steam explosion, you are right.

Just for comparison, the explosion from Chernobyl was described as a "huge explosion with a giant fireball" (at least that's what I heard from eye witnesses).