Saturday, September 24, 2011

TEPCO: It May Be 100% Hydrogen Gas Inside the Pipe Connecting to Reactor I Containment Vessel

First it was reported that "over 10,000 ppm" or over 1% of hydrogen gas was detected at 2 locations in the pipe that connects to the Containment Vessel of Reactor 1 at Fukushima I Nuclear Power Plant. Then it was allegedly "over 40,000 ppm" or 4%.

According to Jiji Tsushin, TEPCO thinks the hydrogen gas concentration in the pipe may be 100%. 1,000,000 ppm.

Still, TEPCO says possibility of explosion is not necessarily high because there is no source nearby that could cause sparks. (Never mind that they were going to use blow torches to cut the pipes...)

Jiji Tsushin (12:28PM JST 6/24/2011): 


Concerning the detection of hydrogen gas in more than 1% concentration inside the pipe that connects to the Containment Vessel of Reactor 1 at Fukushia I Nuclear Power Plant, TEPCO announced on September 24 that it is highly probable that almost all the gas inside the pipe is hydrogen gas. TEPCO's Matsumoto said in the press conference, "Since there is no source for sparks, it cannot be said that there is a high risk of explosion immediately".


According to TEPCO, they measured the gas at the pipe exit several times in the afternoon of September 23. Each time, the result showed "flammable gas including hydrogen gas, over 100% ". The company plans to use the instrument that only measures hydrogen, in order to accurately measure the concentration of hydrogen.

It's so TEPCO. First they used the device that could only measure up to 10,000 ppm, and that maxed out. Then they apparently used the device that could only measure up to 40,000 ppm, and that maxed out. So they brought in a bit more powerful instrument, but it measures all flammable gases including hydrogen.

I suppose they were hoping that one of these devices would suffice. But now, even they have admitted that the air inside the pipe may be 100% hydrogen.

(H/T WaveCepter311)


Anonymous said...

Jesus Christ...the people at TEPCO are fucking crazy.

steve the jew said...

where's the O2? radiolytic splitting of water produces 2 H2 molecules for every 1 O2 molecule.

pure hydrogen seems to indicate the predominant mode of H2 production is the oxidation of zirconium and uranium.

Anonymous said...

this is so ridiculous!

they will never be able to handle it! the biggest problem is the water and that will never go away!

c'mon, we're all waiting for the next explotion...

richard said...

this news makes watching fukucam far more adrenaline pumping

Kyotoresident said...

What happens if it explodes?

Anonymous said...

Bad things.

Anonymous said...

The price of less contaminated food rises,ideal if you hold currently worthless inventories.

Harry Guiremand said...

Hmmm "over 100%"
Maybe something was lost in translation?

Anonymous said...

Please backup your blog RIGHT NOW! Google/Blogger just deleted a 1 million/month viewed blog called activistpost with no warning.


arevamirpal::laprimavera said...

@Harry Guiremand, that's exactly what it says in Japanese. TEPCO used the portable gas flammable gas detector that detects all flammable gases including hydrogen gas. It means, I was told, that it went overscale.

Anonymous said...

Depending on how their instrument was calibrated, it could read over 100%, especially if it was not calibrated specifically for hydrogen. The point is moot, however. Anything reading that high in the flammable zone is grounds for removing ones self from the affected area ASAP. They need to trace that line and see where it's going and make sure no oxygen gets into it or it's going to be ugly.

Anonymous said...

to anno 1:11 AM

In principle you are right. In total two molecules of water will split into two molecules of H2 and one molecule of O2 by radiolysis.
[ 2x H2O -> 2x H2 + 1x O2 ]

1. Which gases do we have in the containment & reactor pressure vessel (RPV)?
A. Air (specific gravity (SG) = 1.00)
B. water vapour (SG = 0.62)
C. nitrogen - N2 (SG = 0.97)
D. hydrogen - H2 (SG = 0.07)
E. oxygen - O2 (SG = 1.10)
(see for other gases)

2. What is specific gravity (SG) and what does it mean?
A. SG is dimension less (meaning no unit) since it represent the RATIO between the specific weight of the stated gas against air (thus air = 1) at 20 degrees Celsius and normal pressure (these ratios will not change much inside the RPV/containment despite the higher temperature and pressure there)

B. SG lower than 1 -> the gas will go up (it is lighter than air)

C. SG higher than 1 -> the gas will go down (it is heavier than air)

3. Please remember the drawing of the containment and RPV in the first post about H2 (more than 1% by the magnificent editor of the blog)

A. The pipes leave the containment in the upper 1/3.
B. Since the pipe belongs to the core spray system, it should end inside the RPV in the upper 1/3 of the RPV (above the original position of the nuclear fuel)

4. Wherever the corium is (inside the containment or in the basement), in it's water vapour bubble around it or in the water vapour directly above it, the H2 and O2 are produced by radiolysis.

5. Over time, the H2 gas (since it is so light) will move to and collect at the top of the containment/RPV.

6. The water vapour, injected N2, the heavier O2 and some H2 (that did not manage to escape the gas flow) will leave the RPV/containment via cracks and holes in the lower 1/3 of these structures (probably in the bottom) and eventually reach the basement (a very dynamic process - meaning quite a large amount will be blown/pushed into the basement every hour) and finally the environment.

7) Can the H2 still originate from the reaction of water vapour with zirconium?
A) You need over 800 degrees for a useful reaction rate (a condition I do not believe in at the moment)
B) The zirconium needs to be in direct contact with the water.
B1) At the beginning of the accident (March), there were intact fuel rods with zirconium on the outside getting very hot and in contact with water vapour and thus produced H2.
B2) Now everything is in a giant blob (or some blobs) where everything is pretty mixed in with the control rods, the steel from the control rod mounting and other things that were mounted below the RPV.
B3) The zirconium on the outside of this blob has long reacted with the water vapour and is now inactive (fully oxidized).
B4) The zirconium inside the blob can hardly every reach the surface of the blob to react with the water vapour (even at 1000 degrees corium will have a high viscosity, thus it probably will behave more like a lava flow than like water).
C) Because of A, B3 and B4 I do not think any substantial amount of H2 currently inside the RPV/containment originated from the zirconium reaction (again, back in March this was a different story).

8. What we do not know (maybe TEPCO knows) :
A) How long did it take to build the H2 bubble at the top of the RPV/containment
B) Is there a way for the H2 to escape constantly through the top of the RPV/containment (via small cracks in pipes leading from that area [the top] to the turbines, etc..)

9. If we would know the missing information of point 8 we could get a quite good idea of how the corium is doing and maybe we could conclude how far the corium is already away from the bottom of the RPV.

10. Thank you so much laprimavera for your hard, but extremely valuable work.

Anonymous said...

Sadly, STJ is right, uranium and zirconium are in play here. If steam/H2O makes it through the solidified corium crust once this thing sinks and cools enough to submerge, it will liberate it's own O2. Probably already doing so, but in insufficient amounts to feed an explosion.

In other words, well, acronym, BOHICA, Fukushima is FUBAR. Along with all the rest of us, just at a different pace.


So, we are warned. How much can we really do?

Anonymous said...

I would like to see TEPCO start filming these acts of measurement, video confirmation of procedures. Odd that they do not.

Anonymous said...

Looks like we should be seeing another detonation soon...hydrogen goes BOOM!

Anonymous said...

Can we force the international nuclear industry to live at Fukushima...


I propose an exchange...the children of Fukushima get to leave and the international executives of nuclear energy companies take their place.

Robert said...

1. The last sentence in the article should read "even they have admitted that the gas inside the pipe may be 100 percent hydrogen" Rather than "the air inside the pipe being 100 percent hydrogen" By definition air must contain oxygen. Usually an approximate 18 percent oxygen 80 percent or so nitrogen mixture.
2. Hydrogen and oxygen will burn or explode with two molecules of hydrogen to one molecule of oxygen reacting to form H2O (water.) The higher the concentrations of the reactants (hydrogen and oxygen) versus inert nitrogen in air the greater the danger of explosion.
3. Any spark from any electrical switch or electrical machinery in such an environment can initiate an explosion.
Witness what happened in the early US space program to Gus Grissom and his fellow astronauts when they were rapidly incinerated in the ground testing of a space capsule, in a 100 percent oxygen environment, by by an electrical spark from a circuit breaker.

Anonymous said...

Lets see....

What can cause a spark?
Wire shorting out.
Pipe breaking.
Lighting storm.
A cigarette.
An over-heated fuel rod!
A bad light bulb.

So, some dumb ass can do all but a few of these and then....blewy!

Hydrogen is a bit explosive when it is at 100% saturation. Quick TEPCO, fill party balloons with the gas! Then, sell them to unsuspecting kids! "Kids, they glow green because they are special TEPCO balloons!

All gas and creating more by the minute!

Anonymous said...

I thought the whole point of injecting Nitrogen gas into the RPV was to prevent a Hydrogen explosion by 'consuming all the O2' so there would be no reactant.
The fact that large quantities of H2 are also being produced don't seem to be a problem to them.

They'll probably releasse it (if they can) like last time, and have a nice 'BOOM'.
Maybe not though.

Anonymous said...

Exclusion of oxygen, not consuming, is the intention w/the nitrogen.

Under those conditions nitrogen does not react w/anything, it's inert.

Nitrogen gas is two nitrogen atoms triply bonded to each other, very hard to break.

Does appear they do not have much of a handle on what's going on where, to be still 'discovering' things tells you radiation rules the day.

Anonymous said...

So, how's the construction of an airtight containment around reactor #1 building going? Given that the RPV leaks like a sieve, and really the corium is melting its way downwards in the basement while repeatedly going critical, if there's hydrogen in a pipe from the RPV, there's also hydrogen leaking from the building into the atmosphere. Only no one noticed because it's not radioactive, and rapidly dilutes.

But it won't be diluting once it is leaking into the space within the new containment structure.
Won't that be fun, when it blows! And it will be on Fukucam too...

Afterwards TEPCO will propose to build a third containment structure around the original wrecked building, and the wrecked 'shell' around that.

FUBAR doesn't even come close.
This whole drama could be quite comical, if, you know, one was some kind of space alien and didn't have to live on planet Earth or care about fellow humans.


Anonymous said...

Look on the bright side. At least TEPCO isn't using candles to look for least not yet...that we know of.

Nuclear Power
Safe Clean Cheap
Forever and Ever

Anonymous said...

The nuclear industry would like you to know:

Nuclear Power
Safe Clean Cheap
Forever and Ever

The people radiated by the nuclear industry would like the nuclear industry to know:

Fuck off
Get off this website
Move to Fukushima and stay there.
You will be stripped of every asset your industry has ever had.


Sent from: All of Japan and most of the northern hemisphere. Thanks!

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