The process and the apparatus described hereinbefore are applied to the series of tanks intended for the production of aluminium by the electrolysis of {HEAD ~ alumina} dissolved in {TAIL ~ molten cryolite base baths} and more particularly to the situation where the bath comprises: 
dissolved in
The process and the apparatus described hereinbefore are applied to the series of tanks intended for the production of aluminium by the electrolysis of { HEAD ~ alumina } dissolved in { TAIL ~ molten cryolite base baths } and more particularly to the situation where the bath comprises :
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH