Wednesday, June 22, 2011

Contaminated Water Processing at #Fukushima: Kurion's System Achieved Less Than 1/20 of Hoped-For Performance

AREVA's system fared better, achieving 40% of the hoped-for performance.

The reason? The deadly combo of seawater and very high radioactive materials in it.

According to TEPCO's handout for the press on June 22, Kurion's system managed to reduce the radioactive materials as follows:

Iodine-131

Before the treatment: 6900 becquerels/cubic centimeter
After the treatment: 990 becquerels/cubic centimeter
Decon Factor: 6.97
Hoped-for DF: not known

Cesium-134

Before the treatment: 2,000,000 becquerels/cubic centimeter
After the treatment: 43,000 becquerels/cubic centimeter
Decontamination Factor: 46.5
Hoped-for DF: 1,000

Cesium-137

Before the treatment: 2,200,000 becquerels/cubic centimeter
After the treatment: 48,000 becquerels/cubic centimeter
Decon Factor: 45.8
Hoped-for DF: 1,000

So, Kurion's system achieved less than 1/20 (or 4.6%) of the performance hoped for.

The result for AREVA's system are listed as "ND" (not detected), but it was assumed by TEPCO that AREVA's system's Decon Factor was less than 400, where 1,000 was hoped for. (Information from Yomiuri Shinbun)

By using both Kurion's and AREVA's systems, TEPCO had hoped that the radioactive materials in the water could be reduced to 1/1,000,000.

If Kurion's system reduced the radioactive materials to about 1/46 and AREVA's system 1/400, the combined performance was only 1/18,400, short of the minimum performance needed for the smooth operation of the desalination system (by Hitachi).

Desalination is essential if TEPCO wants to use the treated water as cooling water for the reactors.

TEPCO's Matsumoto said in the press conference that he had hoped that the water treatment system would start running full-scale in a couple of days, but now he wasn't sure when. (Information from Asahi Shinbun)

The Tohoku region that include Fukushima Prefecture entered the rainy season on June 21.

9 comments:

Anonymous said...

Dabe.

Anonymous said...

Question my friend:

If the decon factor for Areva was less than 400, where 1,000 was hoped for, the result is not 1/400 but 400/1000 which would be 1/2.5

Merci

Dominique

netudiant said...

While this is not great news, the reality remains that there is removal of well over 99% of the contamination.
Also, it is essential to reduce the contamination as soon as possible, to reduce the groundwater pollution. So even if the improvement is below expectations, it is still very large and should be expanded if possible.
We can also hope that additional gains can be achieved by further tweaking the system. For a first cut, the performance is actually pretty good, at least imho.

Anonymous said...

Yes, definitely a positive step forward. The question is though, what will they be doing with the contaminants they remove? According to some people a crane came through and pulled some fuel rods out of the pools recently. One can only speculate where they disposed of those, but presumably it was a deep sea burial. In the bad old days Japan has done that with its Nuke waste before, dumping it in the pacific. Surely that is highly likely to happen now with all the waste and rods they can remove. So in a sense, if the process doesn't work, at least that keeps the waste where it is, rather than being dumped in someone else's back yard.

Anonymous said...

Robbie001 sez:

This isn't a problem, all they need to do is run the system 72 hours a day at double output and soon enough everything will be popping up puppies and kittens.

I'm sure they didn't account for dealing with contaminated salt. I'd guess they are trying to figure out a way to recirculate the the effluent back to the filter column before the desalination stage so they can lower the contamination level enough to make some "moonshine".

I want to know how they are dealing with the radioactive oil that they are stripping off? It is probably pretty "hot" I wonder how much of it they have to deal with?

Anonymous said...

A crane pulled some rods out of a spent fuel pool and dumped them in the sea? Is there any truth to this?

Anonymous said...

Robbie001 sez:

I don't think it would help the offshore contamination situation to dump fuel assemblies into the ocean. Most of the fuel at Fukushima is probably rife with fuel pin integrity problems. Then again it wouldn't be like it hasn't happened before elsewhere.

"RADIOACTIVE WASTE DISPOSAL AT SEA

History
The London Dumping Convention of 1972 regulates the disposal of hazardous wastes into the oceans. The Soviet Union was a member of the London Dumping Convention, and thereby obligated not to dispose of certain types of highly radioactive waste at sea. In the late 1980s, however, Soviet citizens began to voice concern over reports regarding the emergency sea-based dumping of low-level radioactive waste and nuclear reactors. Initially, reports focused on the radioactive waste dumped into the sea by the Murmansk Shipping Company, which operates Russia's fleet of nuclear icebreakers. But by 1992 attention had shifted to the dumping of radioactive waste by the Russian Navy. According to one source, the Navy had dumped 12 damaged submarine reactors, five of which still contained fuel, into the Kara Sea and areas near Novaya Zemlya".

http://www.nti.org/db/nisprofs/russia/naval/waste/wasteovr.htm

Anonymous said...

All these "Experts" from TEPCO or from elsewhere are either cheating us or are completely incompetent. This decontamination system cannot work at all, which can be shown by a simple analysis. The numbers given in the text above sum up to an activity level of 3.9 Sv/h for the water. This radioactivity cannot be neutralized or "destroyed", you can only transfer these radioactive substances (I-131, Cs-134 and Cs-137) from the water to an absorbant medium (the zeolite). If you acheive this to 100% and the absorbing medium should have an activity level of 4 mSv/h maximum, you would need 3900/4=975 tons of zeolite to decontaminate 1 ton of water. Even when you accept an activity level of 4 Sv/h for the zeolite you would need 0.975 tons per ton of water. The 16 cylinders have a volume of approx. 24 m^3 giving approx. 50 tons of zeolite. This means you can decontaminate either 50 kg (4 mSv/h) or 50 tons (4 Sv/h) of water with one filling. For the decontamination ratios of approx. 46 given above, the numbers would change only marginally, resulting in 98% (100%*(1-1/46)=97.82%) of the figures presented above. The conclusions to draw from this is up to the reader.

With kind regards from a german reader of your blog

Jp said...

to "german reader":
- if you achieve 100% of decontamination, then the result is 0 contamination. Simple maths really.
- from where do you take that you need 1 ton of zeolite for 1 ton of water? Then your theory crumbles.

The conclusion is draw from your "maths" is that you are the incompetent one.

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