Fukushima nuclear disaster re-created - Bang Goes The Theory - BBC

Jem Stansfield, recreates a damaged nuclear reactor core, simulating the disaster at the Fukushima nuclear power station.

Bang Goes The Theory, investigating the science behind the headlines and making sense of the everyday issues that matter to us all.

[lanceshelton]

YOU DIDN'T SEE STYROFOAM, BECAUSE ITS NOT THERE!

[krumplethemal]

Well I see the problem. You aren't suppose to create the cap of your reactor out of styrofoam. 

[benson]

Fukushima engineers used Styrofoam as roof containment.

[Ryukachoo]

hydrogen explosion blowing apart a concrete building. the concrete gets pulverized and tossed extremely high up, and the heat from the blast causes the "mushroom", which is really caused by an updraft within the plume.
look, if you're going to claim one of the reactors actually went supercritical (nuclear detonation), at least read what that actually means, and realize it's fundamentally impossible to do this with a boiling water reactor. the density is nowhere NOWHERE near high enough

[fluffybunny]

"You didn't see graphite, because it is not there"

[fierodough]

American nuclear engineer Arnold Gundersen, noting the much greater power and vertical debris ejection compared to the Unit 1, has theorized that the Unit 3 explosion involved a prompt criticality in the spent fuel pool material, triggered by the mechanical disruption of an initial, smaller hydrogen gas explosion in the building. Low-dose radiation researcher Christopher Busby speculated that the explosion that destroyed the Reactor 3 building was a "nuclear explosion" in the spent fuel pool.

[jeanclaudejunior]

Good job solving the mystery of the Fukushima thing

[conorwhyte]

I completely agree with Alexander Alcyone's opinion and this can be backed up with some of the Gamma Spectroscopy kits given by open source groups online to farmers and those people around the area. Most of the contamination is in the form of Cs137, Cs134 and very short lived Radio-iodine (I-131) from reactor fuel. None of the heavier elements like Uranium or Plutonium in the MOX fuel escaped into the air like at Chernobyl, which was a totally complete containment failure.  Yes, there was partial melting at 3 of the reactors and this has caused significant groundwater problems. It is NOT airborne!!!
If any mox fuel was blasted into the air like some are suggesting here, we'd have seen traces of it in our rain water in N.A. which we haven't.  Plutonium is very easily detectable with a low energy Gamma Scintillation detector.   
    "over 20 tons of MOX was blasted into the air"  comment below is utter nonsense and a worse situation than what occurred in Ukraine in 1986.  Btw, the event at Chernobyl sent a massive cloud of fallout over Northern Europe and was even detectable in North America some weeks after the accident.

[meuk]

The nuclear material did not leak out. It is the water that has been used in the cooling process that is causing the issue. They are extracting and storing it, but some has escaped into the ground water system. The nuclear material in the plant itself poses no threat at this time.

[fishgil]

Actually, It can happen, what happens is that a neutron is shot with precision at an atoms nuclei center(Uranium Iso-238, 5-20% Iso-235) In a successful attempt, cause it to literally slit in half, releasing 2 elements, and also energy, and 2-3 neutrons.

In an uncontrolled nuclear chain reaction,
What happens is the chain reaction is going so fast that in a fraction of a sec. billions of atoms will split in half releasing energy, nuclear energy in the form of heat, light, and gamma rays.

After exploding, anything in the radius will likely get vaporized at a temp. of 4000* C. or 7000* F. After that within a fraction of a sec. a shockwave at the speed of 716 nearly hitting mach 1. Thus releasing too game rays (Y) causing air and rain to be radioactive, considering the decaying speed of the radioactive particles.

Now not having a fail safe is just plain stupid, if there had been a failsafe all control rods would have pushed home, thus taking away all the heat to the cooling plant.
There going into a boiler, creating energy.

[arclight]

recreates a damaged nuclear reactor core .. he actually shows what happened in daich 2 and maybe daichi 1 (no one can get near it)
not 3 and not what happened afterwards..

[doright]

The pacific IS boiling just not there. . just at the volcano. seafood gumbo. Got Butter!

[arguescreamholler]

If hundreds of times more radiation is released from an accident than a bomb does it matter if it has as much explosive power?

[domenicopaone]

What the dosimeter says?
3.6 Roentgen but...
3.6 not great not terrible

[AlMayer]

The supercriticality didnt occur in the reactor. It occurred in the SFP of #4.

[brendanwood]

Yeah, well they could not have vented all of the steam or there would not be anything to keep the reactor cool. Also, the real problem not discussed in this video was the lack of power to the facility following the tsunami. The pumps to add and circulate additional water could not operate without power. There were two valves that should have been opened manually to allow the steam to travel into the emergency condenser. However, lack of proper training lead to a failure to do so. Instead technicians thought that they would open automatically. So the temperature inside the reactors rose and rose until even metal could be vaporized. This cause the material to burn through the concrete and metal below the reactor and form a molten mass of metal. This much like Chernobyl could be like a weak dirty bomb if anything fell on it with sufficient mass and kinetic energy. This is a total downplay of the disaster. Just look at recent news. 

[primodernious]

its exactly that gas build up that happens when a volcanoe erupt. the gas build up intil the cavity explodes. the magma have no enough pressure to penetrate the ground so a cavity of gas builds up tanks to the decacy of particles resulting in light isotopes that create the gas build up that eventually explodes. without nuclear fission there would be no volcanoes. radon gas leaks out of both volcanoes and mountains. there is no reason why elements like uranium and plutonius chould be in 99 percent purity in any place on earth but such concentrations of radioactive matter would be needed to form volcanoes. is it not strange that so many volcanoes on earth are close to the ocean just like nuclear reactors? is it not strange as well that the volcanoes many times lines up with more or less even space apart?

[arclight]

30 children with thyroid cancer already.. (smoke and alcohol? average age 15 :( )

[arclight]

hi ryukachoo
why was there such a huge mile high mushroom cloud? the other hydrogen explosions were diffuse and much smaller, the dust was black and that reactor happened to be running on MOX fuel.. so the question NO ONE asks is.. did MOX cause an larger and more powerful explosion?
"..(nuclear detonation) .." or mox indused mini nuke.. ??

the military use depleted uranium to help induce extra heat and blast potential..

does MOX fuel have something that does similar??
thx for the reply.

[tensevo]

Excellent presentation.
When you say, "can never become nuclear bombs"
the proliferation of weapons grade uranium presents nice collectibles for potential terrorists.