PROCESS OF APPLYING LINING TO CATHODE PART OF ALUMINUM ELECTROLYTIC CELL Russian patent published in 1994 - IPC

FIELD: process of applying a lining to cathode part of the aluminum electrolytic cell. SUBSTANCE: laid and calcined are carbon heath, heat-insulating layer and an intermediary one made of clay brick or more precisely of shaped sun-dried clay brick having 1-5% impurities being burnt away. The intermediary layer is put in the zone ranging in the operating temperature from 740 to 920 C. The layer thickness is equal to 0.2-0.6 height of the carbon hearth. The sun-dried brick is calcined simultaneously with the above-mentioned carbon hearth. Thus any special calciners are unnecessary and capital costs of brick manufacture reduce. The heating of the cathode lining is at first accompanied by a final drying of the sun-dried clay brick with the calcination following. The latter process operates similarly to treating the sun-dried clay brick in calciners with the difference that the heat of combustion generated by the impurities being burnt away is simultaneously utilized for initiating chemical reactions in the sun-dried clay brick and also for heating the carbon hearth. This assures reduced power consumption at calcining the hearth. The two-sided heating of the hearth results in reducing its deflection. This prevents blocks and their joints from cracking. On calcining the hearth will hold its integrity so that the electrolytic cell can increase its useful life. EFFECT: reduced power consumption on calcining the hearth of the cell which may be associated with an additional heat source arranged under the above-mentioned carbon hearth; increased service life of the electrolytic cell. 1 tbl