As you will all remember, TEPCO’s plans for decontaminating the ever increasing amounts of radioactive water accumulating at Fukushima depend upon their ALPS decontamination system. Recently the first hot runs of this system commenced and now a report has been issued in Japanese only on Nov 29.
The crux of the problem, as explained by EX-Skf below, is that the huge system was designed on the premise that the radioactivity in the water was in the form of ions. As it turns out, this is not the case at all. Most of the radioactivity is bound up in the form of colloids and particulates which are much larger than ions.
More than 93% of cesium-137 in the post-RO (reverse osmosis for desalination) waste water exists as “colloids”, less than 2% as “ions” and 5% as “particulates”.59% of all beta (strontium-89, -90, Y-90) exists as “colloids”, 37% as “particulates”, and 4% as “ions”. The existing absorption materials (in [ALPS} vessels) can only remove these nuclides in “ion” form.
So the figures reported above mean that this huge ALPS system can only remove less than 2% of the cesium and about 4% of the strontium and other beta contamination. All the rest in the form of colloids and particulates must be removed by the PRE-TREATMENT systems before the water enters the ALPS system. As a result, the pre-treatment systems are producing “too much” waste material. One can only interpret this statement to mean that that once again the storage of radioactive slurry and filter media from these pre-treatment systems is a huge problem for TEPCO.
What a colossal and expensive design error. (Reminiscent of the large in ground storage pools, which were intended to hold the contaminated water prior to treatment and had to be abandoned since they were designed improperly and leaked.) See the pictures of the massive ALPS treatment system and the huge building that contains it at the end of the Ex-SKF story linked below.
The outcome of all this is that the ALPS decontamination cannot do the job it was intended for and it is back to the drawing board yet again on the treatment and storage of radioactive water and sludge. The only good news here is that TEPCO will not be dumping the expected volumes of treated water into the ocean until they can design and build a system that does not produced so much waste product. If that is even possible…
http://ex-skf.blogspot.ca/2013/12/fukushima-i-npp-multi-nuclide-removal.html (Monday, December 30, 2013)
Fukushima Update # 84: January 1, 2014, Web Exclusive
