DEVICE FOR MEASURING THE ALUMINUM OXIDE CONTENT OF A CRYOLITE BATH IN AN ALUMINUM ELECTROLYSIS FURNACE

摘要

THE INVENTION CONCERNS A DEVICE FOR MEASURING THE ALUMINUM OXIDE CONTENT OF A CRYOLITE BATH IN AN ALUMINUM ELECTROLYSIS FURNACE HAVING A GALVANIC ELEMENT CONTAINING AN OXYGEN CONCENTRATION AND A SOLID ELECTROLYTE CONDUCTING THE OXYGEN IONS, WHICH IS AVAILABLE, WITH A COMPRESSING ELECTRODE OF A POTENTIAL OXYGEN DETERMINED IN A ZIRCONIUM OXIDE TUBE CLOSED AT AN END AND WHICH IS PROVIDED WITH A MEASURING ELECTRODE WITH ALUMINUM COATING WHICH IS PLACE IN CONTACT WITH THE CRYOLITE BATH; COMPARISON ELECTRODE 7 IS CONSISTED OF SUBSTITUTED ALO SURFACE MOLTEN CRYOLITE WHILE THE ALUMINUM COATING OF MEASURING ELECTRODE 9 IS, BY CONTRAST, CONSISTING OF MOLTEN ALUMINUM 2 LOCATED IN THE OVEN AND IN WHICH TO PENETRATE THE SAME CURRENT DRIVER 11 OF MEASURING ELECTRODE 9; THE CURRENT DRIVER 11 OF MEASURING ELECTRODE 9 IS PROVIDED WITH A PROTECTIVE COATING 10 IN BORON NITRIDE. / P