V
crystalline matrix, the amorphous
one very often sustains unexplained
reversing to aging results. The only
ongoing experiment for assessing
the aging of amorphous glass for
HLW vitrification is underway in
China and is currently in its 16th
year of testing.
itrification of radioactive
high-level radioactive waste
(HLW) in boron silicate glass
is the primary technology
used for encapsulating radioactive
HLW. However, the model assumes
certain critical assumptions for containment. A major assumption is
that amorphous glass can stably
sustain radioactive HLW with no
significant degradation over
time or release of radioactive materials. A key
assumption for containment is based on the
existence of ancient
archeological glass
artifacts and computer models for
the boron silicate
glass.
H o w e v e r,
the technical
modelling assumptions to support
computer simulation are based on
some incomplete or ungrounded
assumptions. The limited laboratory tests for glass aging (i.e. repeated heating and cooling) ignores the
important point that, contrary to
The glass vitrification process
is based on forming glass
boron silicate in an amorphous composition at a
melting temperature of
around 650 degrees.
At such a temperature range, the glass
matrix
prevents
evaporation of the
selected radioisotopes (e.g.
Cesium). The
next
step
is to mix the melted amorphous
boron silicate glass with solidified
highly radioactive HLW in proportions of around 63% to 67% glass
and 33% to 37% solid radioactive HLW material (some mixing
issues remain unresolved). The hot
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