Constellation, le dépôt institutionnel de l'Université du Québec à Chicoutimi

Résumé

In the Hall Héroult process, the prebaked anode is consumed until a critical thickness of carbon is used. At this point, the anode assembly including the cover material is removed from the pot to be recycled for further use. To do so, the cleaning process should have the ability to efficiently and properly separate the different materials. However, this step becomes less efficient when carbon cracks and breaks during the cover material separation step. In this paper, the thermomechanical behaviour of the anode butt is investigated to identify the origin of carbon cracking . The ANSYS model is calibrated using in situ measurements and provides the evolution of the stress distribution in the anode butt during service life and cooling phases. The results suggest that carbon cracking mainly occurs during cooling phase and is especially sensitive to the thickness of the anode butt and cover material.