Holy Crap Japan!!!

#1
http://www.thejournal.ie/what-happened-in-japan-timeline-of-the-terrible-events-2011-03/

Last updated: 1pm: scroll down for the latest.

All times are given in JST unless otherwise stated. To convert to Irish times, subtract 9 hours.

HOW THE HORRIFIC events of today are continuing to unfold in Japan and the Pacific Rim:

* Wednesday: A major 7.3 magnitude earthquake hits in the area where today’s will occur. But it seems that was just the prelude to today’s massive quake, which is the seventh largest ever recorded.
* 2.46pm: A magnitude 8.9 quake strikes on Friday afternoon, in the middle of the working day (5.46am Irish time). The epicenter is 80km from the eastern coast of Honshu island, Japan’s largest, about 380 km northeast of Tokyo. The depth is 10km, which is relatively shallow – increasing the likely damage. In downtown Tokyo, large buildings shook violently. Power goes out in more than 4 million buildings.

* 3.15pm: A 7.4 magnitude aftershock hits.

* 3.15pm: Half an hour after the initial quake, tall buildings are still swaying in Tokyo, and mobile phone networks have collapsed.

* 3pm-4pm: Over the next hour, Japan is struck by five powerful aftershocks. All public transport stops in Tokyo. Hundreds of people are evacuated from Shinjuku station, the world’s busiest, to a nearby park.The ceiling collapses in Kudan Kaikan, injuring an unknown number of people.
* A massive tsunami – some say it’s ten metres high – swept over the embankments in Sendai city, washing cars, houses and farm equipment inland. Gas explosions rock some houses.
* A large section of the ceiling at the new airport at Ibaraki – about 80km northeast of Tokyo collapses. Tokyo’s main airport closes.
* Residents could be seen waving for help from the top floor of their homes, with surroundings streets flooded, trapping them inside their homes.
* An oil refinery in Chiba prefecture near Toyko caught fire, smoke seen billowing from the industrial site.
* The Japanese government sets up an emergency response team, headed by the Japanese prime minister.
* Dozens of fires are reported in northern prefectures of Fukushima, Sendai, Iwate and Ibaraki. Houses collapsing and landslides were also reported in Miyagi.
* A large ship swept away by the tsunami rammed into a breakwater in Kesennuma city in Miyagi prefecture.
* Scores of cars were shown floating in Iwate prefecture harbour, while the Tokyo Fire department said many people were injured after a roof caved in during a school graduation ceremony at a hall in east Tokyo.

* 4.30pm: People in Hawaii are being told to evacuate their homes. Sirens are sounding in Honolulu. The Pacific Tsunami Warning Center in Hawaii widens its tsunami warning to include Hawaii and the rest of the Pacific Ocean. The tsunami is due to hit – in about four hours – or at approximately 1pm Irish time.

* 4.36pm: Japanese government is notified that the cooling facility at a nuclear reactor is not functioning.

* 5pm: Japan’s prime minister says quake caused ‘major damage’ in northeastern Japan.
* One death is confirmed. Japan’s fire and disaster management agency says it’s still assessing damage.
* 5pm: Authorities in Japan warn residents to prepare for more strong earthquakes.
* The International Red Cross warns that some of the tsunami waves could be higher than some of the Pacific islands.

* 5.06pm: Eight people are now confirmed dead.

* 7.05pm: The death toll is confirmed as 26. The people of Indonesia are warned to expect the first wave of the tsunami in 45 minutes, at 10.57pm local time – or just before 11am Irish time.
* A magnitude 4.5 quake has hit Hawaii.

* 7:38pm: The death toll how now reached at least 29 people, police and authorities have said, while some news agencies are putting it as high as 32. AFP quotes the National Police Agency as saying “the damage is so enormous that it will take us much time to gather data”.

* 7.53pm: New Zealand has issued its own tsunami warning. Small tsunamis have hit the coast of Taiwan without any damage.

* 8pm: Revised time for the tsunami to hit Indonesian province of Papua is 8.30pm – roughly 11.30am.

* 8.18pm: Japan has declared a state of atomic emergency after a cooling failure at the Fukushima nuclear plant. A fire is raging in the Onagawa nuclear plant in Miyagi.
* Russia, Australia and New Zealand have been given the all-clear.

* 8.40pm: It’s reported by the Kyodo News Agency that the tsunami has carried away a ship with 100 people on board.
* Strong waves have been recorded along the Isabela coastline and in Batanes, in the Philippines, ABSCBN news reports.

* 8.43pm: Barack Obama has offered his condolences to the people of Japan, and the US State Department tweets that it has been in touch with the Japanese government and is ready to provide any assistance needed.

* 9.19pm: The European Union has said it would “mobilise all appropriate assistance” to Japan.

* 9.30pm: Japan accepts the US offer of help. It’s reported by the Kyodo News Agency that senior government officials are heading to the Fukushima nuclear plant, which is experiencing a reactor failure. More than 2,000 residents in the area have been urged to evacuate.

* 9.30pm: The death toll from the quake rises to 60.

* 9.45pm: The tsunami is reported to be 20 minutes from shore in Hawaii.

* 05:00am (PST) In the US, the San Francisco Police Department has closed the Great Highway from Point Lobos/48th Ave to Lake Merced as a precaution (1pm Irish time).

* 10pm: In the Philippines, residents are told the tsunami will not be as severe as had been expected (1pm Irish time).

* 10.03pm: In Japan, government officials repeat that there have been no radiation leaks so far from Fukushima. Twenty five countries now offer help.

All times are given in JST unless otherwise stated. To convert to Irish times from JST, subtract 9 hours. Irish time conversions from other time zones supplied.
 
#3
* 8.43pm: Barack Obama has offered his condolences to the people of Japan, and the US State Department tweets that it has been in touch with the Japanese government and is ready to provide any assistance needed.

why does this one stand out to me? tweets? really?

This is not going to pan out well.
 
#7
My point is I think its stupid that the gov uses Twitter as a means of communication. I'd hate to know how much they pay some idiot to sit behind a computer and tweet all day long.
 
#8
Since I work at Oconee Nuclear Station, their nuclear plants were of particular interest to me and coworkers. The plant that had the fire had it in a non-nuclear portion of the facility from what we've heard. The one that lost cooling to the reactor was due to electricity being out. They had backup diesel generators, but they shut down 1hr after start because the fuel tanks for the gen's were swept away by the tsunami.
Their buildings are a little different design that Oconee's. Background: PWR's (Pressurized Water Reactor) is what Oconee uses. We have 600 deg F water pressurized to 2200# that stays liquid the entire time, but circulates through the reactor. That water heats another system of clean, non-nuclear water and turns that clean water into steam. That steam turns the turbine/electrical generator. After that, A third system of water (Lake Keowee) is used to cool that steam back into water to be sent back to take more heat from the reactor. Our reactor buildings are designed to take massive hits from the outside and to withstand internal pressures of 60# (keep in mind the building is 8 stories tall and 80 yards in diameter, so thats a BIG air tank if needed).
A BWR (Boiling Water Reactor) is where the water that directly flows around the fuel is heated until it turns to steam, then that nuclear steam turns the turbine/electrical generator. Then, a second system (sea water at the Japan plants) is used to cool the nuclear steam back down to water to be sent back into the core of the reactor.

The Japanese have also been using a little different terminology. They are calling their Reactor Building the metal building that sits around/on top of their "inner containment" building. Their reactor vessel is inside of the inner building, which is reinforced concrete with a steel liner (the building, not the vessel).

So, after they lost their cooling, their reactor system started heating up and pressurizing more than normal. They began venting some pressure off from their reactor INTO their "reactor building" (their outer metal building). If the fuel rods get to hot, they start reacting with water to produce hydrogen. As they were venting into the outer metal structure, they were venting hydrogen into it as well. Some time later, an aftershock ignited the hydrogen inside of the metal building, and it exploded. From everything we've heard today at work, Only the outer structure was damaged. The inner, concrete building that houses the reactor and fuel, were NOT damaged. Also, from their investigations, the vessel itself was still intact. Some time after the explosion, they began pumping seawater into the inner containment in order to cool the vessel/fuel. Later, a second reactor lost cooling ability as well at the same facility. The last I heard, they were beginning to vent pressure off from that reactor as well, but had not decided to pump in seawater yet. Also, backup generators and batteries were being delivered to the site to restore cooling ability to second reactor.

I do not know about the rest of the reactors at that facility. If one doesn't have electricity, none of them should. I know our reactors can go into "natural circulation" where when electricity is lost, the natural convection in the reactor can maintain cooling as long as you can transfer the heat to the second water system. We have a steam driven emergency feedwater pump that can circulate that water. I wish I knew more about their systems. We also have emergency diesel generators, but they and their fuel tanks are underground in a concrete bunker.

They have been talking about radiation being released, but the amount so far is minimal by the actual numbers we have heard. They are manually having to vent the reactors, and the men that are doing that are recieving twice the amount of radiation in one shot that the NRC says we in the US can get in one YEAR. Even still, that is not enough to kill them, but it does start inducing tissue damage and possibly future cancers. Here at our plant, you would have to volunteer for that type of dose.

It's definitely not a good scenario over there, but the nuclear aspect isn't as bad as the media is making it out to be. Even if fuel meltdown occurs, as long as the inner containment building is intact, it poses no public threat.

If I hear anymore details (these were relayed to our plant from the NRC who have been in contact with Japan's nuclear people),
I'll let ya'll know.
 
#11
As of today, I hear the second reactor they were having issues with also experienced an explosion in their OUTER containment building. It was also because of hydrogen venting out. They report that the inner containment and vessel are unharmed. They also had began pumping seawater into the reactor core before the explosion.
 
#12
Here is an excellent pic I found of their containment/reactor buildings. Compare it to the pic of the post explosion at the two Japanese reactors. You can see just the sheet metal portion of the outer containment is gone.
Here is a pic of one of the outer buildings after the explosion.
daichi.jpg
 
Last edited:
#16
hey brent, does this sound accurate?



Fukushima Dai-1 uses six boiling water reactors to produce electricity. At the time of the earthquake, three reactors were active and three were down for routine maintenance.

Let's start at the heart of a boiling water reactor where the nuclear fuel dwells. In most of Fukushima Dai-1's reactors, the radioactive element uranium is the source of the nuclear fission reaction: when one atom of the uranium isotope U-235 breaks down into smaller parts, it produces both energy and neutrons. When a large enough quantity of uranium fuel is gathered together it starts a self-sustaining chain reaction, in which emitted neutrons smack into other uranium atoms and cause them to split in turn. The energy from the fission reaction is used to boil water into steam, which drives turbines to produce electricity.

Pellets of uranium fuel are contained in long, narrow fuel rods made of an alloy of zirconium. There are thousands of these fuel rods inside a reactor's innermost chamber, which is called the pressure vessel. Water inside the pressure vessel keeps the fuel rods from overheating, and also creates the steam for the turbines.

The pressure chamber is encased in a protective steel shell called the primary containment vessel. Ringing the base of that containment vessel is a doughnut-shaped structure called the torus, which serves a safety function: If pressure rises too high in the pressure vessel, operators can vent steam into the torus through a series of relief valves. (The torus will be important when we explain what went wrong in Fukushima's No. 2 reactor building.)

The primary containment vessel and the torus are in turn encased by the secondary containment building, a large box of steel and concrete.

What Went Wrong

When the 9.0-magnitude earthquake struck offshore on Friday the Fukushima Dai-1 plant on Japan's northeast coast was not badly damaged, and its emergency shutdown procedures went into effect. The first step went fine: To stop the nuclear fission chain reaction, control rods with neutron-absorbing properties were inserted among the fuel rods.

But even though the fission reaction came to a halt, the danger wasn't over. Radioactive byproducts of past fission reactions continued to generate heat inside the pressure vessel even though the reactor was no longer active, so cooling systems were supposed to kick in to circulate cold water and remove steam. But the tsunami that swiftly followed Friday's earthquake swamped the coastal facility and damaged the generators and power systems that ran Fukushima Dai-1's cooling mechanisms. That's when things started to go bad.

Reactors No. 1 and No. 3

The plant's operators rushed in new generators and turned on battery-powered backup systems, but apparently this gear couldn't keep the recently active reactors from heating up. It happened first in reactor No. 1, where high temperatures inside the pressure vessel evaporated too much of the water inside the chamber. When the water level dropped, the zirconium alloy fuel rods were exposed to steam and other gases, which caused reactions producing hydrogen.

As pressures in the inner chamber reached dangerously high levels, operators decided to vent steam (containing some radioactive elements) first into the primary containment vessel, and then into the secondary containment building. But the volatile hydrogen gas appears to have reacted with oxygen in the secondary containment structure, causing an explosion that ripped the roof off the building on Saturday. While this explosion did release some radioactive material, experts believe it did not damage the primary containment vessel.

A similar chain of events tore the roof off reactor building No. 3 on Monday morning. In that building, operators had resorted to pumping seawater into the pressure chamber to cool it, but they weren't able to prevent the explosion. TEPCO officials initially said that the No. 3 primary containment vessel wasn't damaged. But on Wednesday white steam began to rise from building No. 3, raising fears that the primary vessel had, in fact, cracked due to the explosion. If the steam was leaking from the primary containment vessel, it was likely to be contaminated with radiation.

Even if the primary vessels weren't damaged in these two reactors, however, extremely high temperatures in the reactors may have melted parts of the zirconium alloy fuel rods, and may have even melted some of the uranium pellets themselves. That's a serious concern, because melted uranium could drip down and pool at the bottom of the pressure chamber. If enough of it gathers there, it could begin to eat through the chamber's walls and then the primary containment vessel. That worst-case scenario is commonly referred to as a "meltdown." There is also a danger of the fuel collecting and momentarily re-igniting a self-sustaining chain reaction. But TEPCO doesn't yet know whether any fuel rod melting has occurred in reactors No. 1 and No. 3.

Plant operators are continuing to pump seawater through reactors No. 1 and No. 3 in an effort to keep them cool and avert any further explosions. The corrosive salt water has rendered the reactors unfit for future use.

Reactor No. 2

The accident in the No. 2 reactor building, which occurred Tuesday morning, was seen as more serious than the prior two explosions because it was the first blast that involved a primary containment vessel.

The incident occurred while operators were trying, with limited success, to pump seawater into the pressure chamber. According to reports, the vents intended to release steam and relieve pressure were stuck closed, and the high pressure inside the chamber prevented the injection of seawater. As the water level in the chamber stayed obstinately low, the fuel rods were reportedly fully exposed to the air for six and a half hours beginning on Monday evening. Commenting on the crisis in the No. 2 reactor, TEPCO said it "could not deny the possibility that the fuel rods were melting."

The blast in reactor building No. 2 is thought to have occurred in the torus, when operators were venting steam into the structure to relieve pressure in the pressure chamber. It's thought that hydrogen exploded within the torus, damaging the primary containment chamber. The fears here are twofold: If the uranium fuel pellets in reactor No. 2 have partially melted, then any steam and water from reactor may be contaminated with radioactive material. And if the primary containment vessel is breached, then it becomes more likely that the contamination won't be confined to the reactor.

Yukiya Amano, the director general of the International Atomic Energy Agency, told The New York Times that there was a “possibility of core damage” at reactor No. 2. According to Amano, less than 5 percent of the nuclear fuel in reactor No. 2 was estimated to have been damaged.

Reactors No. 4, 5, and 6

These three reactors were offline at the time of the earthquake, but they have now become another source of concern. Fires broke out in reactor building No. 4 on Tuesday and Wednesday, and TEPCO officials have warned that fires are possible in the other two buildings as well.

In these three buildings, spent fuel is stored in water-filled tanks, which keep them cool. In reactor building No. 4, the water temperature reportedly rose from 40 degrees Celsius to 84 degrees Celsius. It's likely that the fuel rods overheated, causing the zirconium alloy cladding to partially melt and react with water or steam. That would have produced volatile hydrogen gas, which could have sparked a blast. According to reports, the actual substance burning in building No. 4 was lubricating oil used in machinery near the storage pool.

The fires in building No. 4 appear to have gone out, but concerns remain that the spent fuel in all three buildings is too hot. The smoke from the fire in building No. 4 is thought to have drastically--but temporarily--increased radiation levels around the reactor, so operators are very keen to prevent more blazes.

http://spectrum.ieee.org/tech-talk/...er-what-went-wrong-in-japans-nuclear-reactors
 
Top