vertical potshell deformation may have a negative impact on the
operations of very high amperage cells.
therefore extended to take into account the displacement of the
potshell. The MHD cell stability behavior of a 500 kA cell with a
17.3 meters long potshell was then studied.
collaboration efforts by the authors to investigate if there is a
technical limit to the size of an aluminum electrolysis cell that can
be designed, built and successfully operated.
limit dictated by the heat dissipation requirement hence the need
for the AP50 technology to use an active heat exchanger system on
the potshell in order to enhance the heat dissipation.
to make: because there is a size restriction on the cell width, having
a bigger cell means having a longer cell. Already, length to width
aspect ratio of modern high amperage cells is quite high so they
proportionally do not dissipate much heat by their end walls. Very
simple calculations can be made to demonstrate that a 300 kA cell
operating at 15 kWh/kg would need higher heat fluxes to dissipate
its internal heat than a 740 kA cell operating at 13.5 kWh/kg.
MHD cell stability requirement. This issue was addressed in [1]. It
is known that the modern high amperage cell operating at around
300 to 350 kA can comfortably be operated with asymmetric
busbar network compensating for the effect of the return line
located about 60 meters away. Furthermore, the Bz minimization
requirement imposes that the great majority of the positive side
busbars must go around the cell.
impractical and quite expensive to continue to run most of the
positive side busbars around the cell. In order to avoid to have to
do that, a compensation busbars network like the one presented in
[4] is required.
compensation busbars network is required in order to address both
the cell stability problem and the busbar cost minimization
problem, it was claimed in [1] that it is possible to perfectly
magnetically compensate cells of any length and hence of any
amperage as results presented for a 500 kA and a 740 kA cell
clearly demonstrate.
the cell mechanical design requirements. This argument is not often
even raised, but as discussed in [2], it may well be the most serious
argument.
deformed laterally. But modern high amperage cells using 100%
graphitic or graphitized cathode blocks and strong orthotropic
potshell do not deform much laterally due to carbon swelling they
rather deform vertically due to their own thermal loading [1,2].
paper) that this vertical deformation can have a negative impact on
the cell operations. The aim of the present paper is to take the first
step in trying to take into account impact of the vertical potshell
deformation on the cell predicted operational behavior.
coupled thermo-electro-mechanical problem. The potshell deforms
due to its thermal load and this thermal load is generated by the cell
heat dissipation characteristics [2].