An investigation of the corrosive wear of steel balls in grinding of sulphide ores

Document Type: Research Paper

Authors

1 Department of Mining, Petroleum and Geophysics, Un iversity of Shahrood, Shahrood, 36199-95161, Iran

2 School of Mining Engineering, College of Engineering, University of Tehran, Iran

Abstract

Ball mills are common grinding equipment in mineral processing industries. Ball wear results from three mechanisms namely impact, abrasion and corrosion. Of these, the corrosion mechanism is the least investigated, due to its chemical-electrochemical nature. Therefore, the aims of this research were to investigate the grinding chemistry influence (slurry pH, solid percentage, water chemistry and gas purging) on corrosive wear of steel balls and to determine the contribution of corrosion mechanism to total wear of steel balls. The results indicated that the mass losses of steel balls could be reduced considerably by controlling the pulp chemistry inside the mill. In addition, the results showed that 73.51% of the corrosion products are generated from the oxidation of steel balls. It was also estimated that the corrosion mechanism accounts for 26.68% of the total wear of steel balls.

Keywords


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