
191Accelerating Removal of Variation
iMPliCAtionS For SMelter Control
Operational experience at the great majority of smelters over the past
20 years has determined that the optimum efciency and cell life are
obtained if the cells can be maintained within the box marked by solid
lines, as shown in Figure12.7. In fact, there are sound physicochemical
and thermochemical reasons for this related to the process design as
indicated earlier.
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Figure12.8 shows some of the consequences of being
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FIGURE 12.7
Regions of “overcontrol” and “undercontrol” in the graph of temperature versus XS ...