Re: Charcoal Impregnated HEPA Filters

[mem122a@lanl.gov (Milton McLain)]

Miroslav,

Re your request for charcoal filtration information, to my knowledge, the
sole unique function for charcoal "filtration" is removal of elemental and
organic-bound iodine radionuclides.  For this application, it is more common
to configure the activated charcoal as a bed through which the effluent air
is passed and the iodine removed by adsorption onto the charcoal.  The
effectiveness of such charcoal adsorption beds is dependent on a number of
factors, especially the residence time for air passing through the charcoal.
Activated charcoal manufacturers (e.g. Calgon) can normally provide you with
needed design data from which you can calculate an effective adsorption bed
for iodine removal.  Your mention of antimony radionuclides is a definite
"puzzlement", since antimony is normally a solid, and should be effectively
removed by HEPA filtration alone.


Milton McLain


>Dear Radsafers,
>
>We are currently looking for charccoal loaded HEPA filters for industrial
>use.  These filters are requested for a certain work to be undertaken in a
>very near future, and as it stands now, the only manufacturer we were able
>to locate is in Switzerland. Their delivery times are quite long.
>
>As a matter of fact, I also wanted to ask for an info from (but not only)
>nuclear power plants staff about some experience with antimony family in the
>air (specificaly, Sb-124 and/or 125) and their "alleged" passing through the
>normal HEPA Filters.  Is there anybody to contact who could give us a
thought.  
>
>Thank you very much in advance.
>
>
>     Miroslav
>
>PS. Standard disclaimers apply.
>---------------------------------------------------------------------------
>If I had an opinion, it sure wouldn't be mine... or my employer's!
>Nazory nemusia v ziadnom pripade vyjadrovat postoj mojho zamestnavatela, 
>ba niekedy ani moje vlastne.
>---------------------------------------------------------------------------
>Miroslav Lieskovsky                               Health Physics Department
>mirolies@nbnet.nb.ca                       Point Lepreau Generating Station
>Phone  bus: (506) 659 2220 ext. 7421                    New Brunswick Power
>Fax    bus: (506) 659 2003                             P.O. Box 10, Hwy 790
>Phone  res: (506) 636 7629                                    Lepreau, N.B.
>e-mail res: miroslav@mi.net                                 Canada, E0G 2H0
>
>
>