Optimization of Operational Practices to Increase the Working Life of Crucibles for Molten Aluminium Transportation
1 Alcoa Aluminio S.A. Poços de Caldas, MG, 37719-900/Brazil
2 Federal University of São Carlos (GEMM), (FIRE Associate Laboratory) São Carlos, SP, 13565-905/Brazil
Revision 02.01.2015, 02.02.2015
Volume 7, Issue 2, Pages 105 - 110
Abstract
This work addresses various aspects that affect the refractory lining performance of crucibles, as they play an important role in the aluminum production process by conveying molten metal from electrolytic cells (pots) to holding furnaces. Based on a systemic approach, the main objective of this investigation was to increase the working life of these crucibles and, consequently, reduce costs associated to aluminum production and refractory maintenance. According to practical results, the optimization of operational practices (i.e., castables’ processing, placing, pre-heating of the lining, etc.) led to a significant increase (up to 83 %) in the average refractory working life. Moreover, after implementing the identified improvements, 91 % of the available crucibles were able to perform more than 400 metal runs and the maximum number of working cycles per equipment changed from 467 to 715. Therefore, in addition to the increase in the availability of crucibles, the enhanced performance of the refractories also resulted in financial benefits, reducing 47 % of the annual maintenance and pre-heating costs related to these materials.
Keywords
crucible, refractory maintenance, pre-heating
References
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