Refractories, copper smelting

Because of the high temperature corrosion resistance and thermal stability exhibited by magnesium-chromium oxide refractories in copper smelting, converting and fire refining furnaces, little research has been conducted on other refractory families. However, the concern for hexavalent chromium (Cr ) as a potentially hazardous waste in spent refractories from copper production furnaces has prompted the recognition that a more environmentally acceptable material is needed for the copper industry. 

However, the relatively mediocre corrosion resistance of the magnesia-based refractories suggests that its high temperature bonding strength is not sufficient, and that application of this material to copper smelting systems would be effective only under relatively static conditions, such as the bottom of stationary anode furnaces. 

Crites, M. D. and Schlesinger, M. E., Corrosion Testing of Chrome-Free Refractories for Copper Production Fiu-naces," Proceedings of Copper 99-Cobre 99 International Conference, Volume Vl-Smelting, Technology Department, Process Modeling and Fundamentals, The Minerals, Metals and Materials Society, 1999, pp. 187-194. 

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