Re: Reducing I-125 counts by filtration

[Franz Schoenhofer <schoenho@via.at>]

At 14:41 29.08.2000 -0500, you wrote:
>I recently came across a paper that was written about 8 years ago detailing
>how to reduce the counts of liquid I-125 waste by running it thru a carbon
>filter (water filter) and then thru a PVC column with resin beads.  The
>author claims to have been able to reduce the counts by up to 85%.  Has
>anyone every tried this or know of any such commercial systems that do this?
>I will try and dig up the article and post more details if anyone is
>interested. 


I have not tried this in practice, but it sounds very reasonable. Charcoal
adsorbs a lot of radionuclides, mostly depending on what chemical form the
radionuclides are present. It absorbs radon and gaseous iodine and
methyliodide in air, so it is most likely to absorb some from waste, of
course depending on the type of waste and the chemical composition of the
iodine. If iodine is present as iodide in ionic form, then anion exchangers
will remove it completely. You did not mention what "resin beads" were
used, but I suppose that it must have been ion exchange resins. I would
overall expect a removal efficiency of almost 100%.

On the other hand I do not see any practical application for that method,
especially keeping in mind that something has to be done with the charcoal
and the ionexchange resin afterward and they are not for free as well as
the apparatus will not be for free. A decay tank is not for free either,
but uncomplicated and reusable without any restrictions.

Regards,

Franz



Franz Schoenhofer
Habicherg. 31/7
A-1160 Vienna
Austria
Tel.: +43-1-495 53 08
Fax.: same number
mobile phone: +43-664-338 0 333
e-mail: schoenho@via.at


Please note my new telephone number at my office!

Office:
Ministerialrat Dr. Franz Schoenhofer
Federal Ministry of Agriculture, Forestry, Environment and Water Management
Radiation Protection Department (BMLFUW I/8 U)
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A-1031 Vienna
AUSTRIA

phone: -43-1-71100-4458
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