ORNL-5388 - the Molten Salt Energy Technologies Web Site

A-8
P = total pressure; N = mole fraction of UF in the UFdHe mixture.
Subscripts 0, M, and K refer to feed gas, fight and heavy fractions,
respectively.
Fig. A-2. Cross Section of the Separation Nozzle System of the Becker Process.
A small 10-stage pilot plant was operated in 1967 to prove the technical feasi-
bility of the process. Following that, a single large prototype stage suitable for use
in a practical cascade was fabricated.
A prototype separation stage contains 81 separatl’ng elements and is reported to
have a separative capacity of approximately 2000 kg U SW/yr. A plant producing a product
enriched to 3% 235U and with tails at 0.26% *35U is expected to require about 450 such
stages .
Figure A-3 shows the individual separating elements, each containing 10 separation
nozzle slits On its periphery. The fabrication of these units is not as simple as one
might at first expect. In order to obtain the desired separation performance at reasonable
pressures, it is necessary to employ very small geometries. The spacing between the knife
edge and the curved wall in the prototype separating unit should be about 0.0005 of an
inch. In order to obtain good performance, it is necessary that this spacing not deviate
by more than +lo% over the 6-foot length of slit.
The power requirement for the Becker process is currently estimated to be about
one and one-third times as great as that required for gaseous diffusion. Dr. Becker
believes that further process improvement is still possible and that the power wquirement
can be substantially reduced.
G
L:
‘il
L
c
ci
L