inventory (after spend fuel recycling) is in the range of 23.11%
for US sludge after 6 years’ decay
to 31.66% for AREVA sludge.
(Reference: Nuclear Chemical
Engineering.)
The Cesium volume to total volume of HLW (after recycling) is
15.226% – for US sludge after 6
years’ decay.
From one side, the atoms’ Radii
difference, combined with the new
lattice configuration in which, two
Cesium atoms are replaced with
one Barium which is an indication of
required additional, almost double
space, the final mineral product will
be required. At the final transition
stage, when the temperature and
the pressure falls under the original
glass transition, Barium Silicate will
undergo an additional solid to solid
dissolution to form Barium Feldspar
(with the presence of Aluminum)
- known as Cyclosilicates (forming
polyhedrons crystalline lattice).
After completion of the 20 half
lives decay time (603.4 years), the
formed Barium silicate will require at
least twice the volume of 30.452%
from the total HLW volume, or
11.267% (63% glass 37% HLW)
additional volume from the total
volume of the originally glass vitrification matrix.
When combined with other decay
chains, an estimate for the entire
HLW radioisotope inventory is that
during geological time transition,
most of the encapsulated steel
containers will sustain significant
volumetric changes such as cracks
or ruptures, that will compromise
the sustainability of the entire glass
vitrification process. The consequences will be extremely disas-
The final question is how to determine how much additional space
the original Cesium in the HLW will
require during its decay transition
to Barium. The average amount of
Cesium in the HLW fission products
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