ORNL-4191 - the Molten Salt Energy Technologies Web Site

An additional purpose of sampling with the
ompartment capsule was to determine
whether foamlike material was present in the
sampler area and would be collected in the upper
compartment. How r, analysis of the upper
compartment has not yet been performed. Globules
were noted on the upper part of FP12-57
(Fig. 8.4), indicating that conditions in the pump
bowl were different n samples FP12-57 and
-55 were obtained.
Examination of the metal basket which contained
the beryllium le it was exposed to
the fuel showed the
along with a small a
ectrochemical anal
moved from the basket (Fig. 8.6) indicated that
the material contained 7.8 wt % chromium and
less than 10 ppm of iron and nickel.
The evidence obtained to date does not permit
inference as to the identity of the phases which
have formed within the pump bowl as a consequence
of the beryllium additions. It does strongly
imply that nonwetted flotsam can be formed and
accumulated temporarily in the MSRE pump bowl.
1
c
114
The overflow tank has not been mentioned as a
possible factor in the behavior of chromium fol-
lowing a beryllium addition. It could, however,
bear some responsibility for the persistence of
chromium for several days following an exposure
of the salt to beryllium. Fuel salt accumulates
in the overflow tan during operation and
remains there in re ation from the fuel
stream. At intervals of about one day, part of the
salt (60 lb) is returned to the fuel stream. Recog-
mium might be injected into the
pump bowl as the salt returns, we performed an
experiment in which salt samples were obtained
from the pump bowl within an hour after fuel was
returned from the overflow tank to the pump bowl.
The purpose of the experiment was to determine
whether material from the overflow tank con-
tributed appreciably to the perturbations in the
chromium concentration. The results were nega-
tive, possibly, in part, because sampling and
salt transfer operations were not performed con-
currently for safety reasons.
Fig, 8.5. Dendritic Crystals and Salt on Basket of
Beryl I ium Add i ti on Capsule F P 12-56.