Re: Co-60 Source Term

["Harald Weiß, D-24147 Kiel" <weiss@ki.comcity.de>]

T Karsten - ESKOM KOEBERG wrote:

> Radiation Protection at Koeberg Nuclear Power Station is looking at
> ways to reduce the Co-60 source term in the reactor coolant.  A large
> number of Stations have done this already, and we are looking at
> international experience on this issue.

 Hi, too,

my knowledge on this subject is neither new nor intimate: some 17 years
ago I reviewed european press for this. Behavior of Co depends heavily
on the combination of temperature and pH-value, so the deposition on
cold or hot surfaces can be managed by coolant chemistry, especially
during shutdown phases, in addition to inertizing the surfaces of
materials containing Co. Unfortunately pH isn´t well defined at higher
temperatures, espacially if you use volatile alkalines (i.e. hydrazine).
At that time the knowledge on the behavior of Co not only differed but
even contradicted between US and western europe on one side and russia
on the other. It was interesting to see that russia showed some very
good results, based on their Co-model. The guys in Loviisa (russian-type
PWR in Finland) did even better, but wouldn´t tell me, what they were
really doing. Perhaps you should have an eye in that direction, too.

Stay clean,      B-{)

Harald Weiss

--
Harald Weiss                 weiss@ki.comcity.de
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D-24147 Kiel                Fax  +49 431 7859658
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