Tuesday, November 1, 2011

Fuku-I Nuke Plant: Nuclear Fission in Reactor 2? Xenon-133, -135 Detected

(UPDATE: Additional information from TEPCO's press conference on November 2 in a new post.)

TEPCO poured the water with boric acid into the reactor to prevent re-criticality.

From NHK News (6:38AM JST 11/2/2011):


Xenon has been detected in the Containment Vessel of Reactor 2 at Fukushima I Nuclear Power Plant. Xenon is created when there is nuclear fission.


The gas management system has been operating since October 28 in Reactor 2 to suck out the gas from the Containment Vessel and filter out radioactive materials. TEPCO has been analyzing the gas to identify the nuclides and density. The analysis done on November 1 found xenon-133 and xenon-135, which are created when uranium-235 undergoes nuclear fission.


Xenon-133's half life is 5 days. TEPCO says it could not rule out the possibility of nuclear chain reaction happening again, so the company poured water with boric acid into the reactor to suppress the nuclear chain reaction for one hour starting 3AM [on November 2].


According to TEPCO, there is not much change in the reactor temperature or pressure, or at the monitoring posts that measure radiation levels in and around the plant compound. Therefore, if the nuclear chain reaction is happening, it is small-scale, says the company. The Nuclear and Industrial Safety Agency says since the density of xenon detected is low and there is no change in the reactor temperature and other parameters, it is hard to imagine the fuel is melting again. But the Agency says it will monitor the situation to see if xenon continues to be detected after pouring in the water with boric acid.

Reactor 2 is where hydrogen gas concentration was rising the other day.


netudiant said...

That is not good at all.
Reactor in meltdown lose the careful fuel/water spacings that slow the neutrons just enough to sustain the fission.
Blobs of fuel do not do that, according to the book.
But if even TEPCO is suggesting that it is happening, even on a small scale, it seems an impossibility has again become real.

Anonymous said...

Well, it might also indicate, that the corium has long left the reactor vessel and is now far enough away from the temperature sensors to allow the measurement of temperatures below 100 degrees.

But that possibility is ruled out be TEPCO because of '?????' ? Yes, exactly that is the reason..... Whoops, sorry there is no reason.

Anyway, no need to worry, it is just 'small scale' -> meaning it is smaller than in March. Hahahaha

Enjoy your radiant life *sigh*

Anonymous said...

What ever happened to cold shut down ahead of schedule?

Anonymous said...

in a democracy where people love their children in a healthy way, the opposition party would call for an election to have normal and reasonable upper limit level maximum of radiation intake per year. The opposition party would win the election and these ridiculous "maximum" limits would be reduced. The population would vote for that opposition party and the government would be forced out.

Anonymous said...

@6:54 PM

I would like to believe that but following the reports, it seems like the majority of people in Japan will choose money/prosperity over "minor" dose of radiation which have not really been "proven" to cause deaths.

The human has this tendency to borrow into the future (atomic waste handling, global debt etc.). Some day, somebody other than us will solve problems created by us.

Anonymous said...

May be the Japanese have discovered "cold fission"! It is true that most inventions were discovered by accidents or failures.

Anonymous said...

@Anonymous, 7:38AM:

There is NO food, which protects your genom from radiation damage. Antioxydants might reduce the effects of ionizing radition creating chemical radicals, so your damaged body cells will die at a slower rate and cancer, heart attacks et al. will hit you a bit later.

But any genetical damage will accumulate and will be passed to and increase with each generation.

After some generations there will be no healty people in Japan at all.

Japanese people will extinct within the next 500 to 1000 years. Or turning into mutated animals living on the trees again.

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