The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 15, 1989
Filed:
Apr. 18, 1988
Benoit Sulmont, St Jean De Maurienne, FR;
Alain Paternoga, St Jean De Maurienne, FR;
Aluminium Pechiney, Paris, FR;
Abstract
Process and apparatus for controlling solid electrolyte additions to electrolytic cells for aluminum production. The invention relates to a process for controlling solid electrolyte additions to a cell for producing aluminum by the electrolysis of alumina dissolved in a molten cryolitic bath according to the Hall-Heroult process. According to this process a nominal value HBC is fixed for the bath height, the level of the bath in the cell is periodically determined on the basis of a fixed dimension point PF known relative to the carbon-containing cathode substrate, from it is deduced the total height HT of the electrolytic bath layer HB and the liquid aluminum layer HM, the thickness HM of the liquid aluminum layer on the cathode substrate is determined, from it is deduced the bath layer height HB, HB=HT-HM and Hb is compared with the nominal value HBC. If this comparison reveals a bath deficiency, a ground bath addition is initiated from a storage means through at least one opening made in the solidified electrolyte crust normally covering the cell. If this comparison reveals a bath excess, an alarm is triggered in order to bring about a bath tapping operation.