Variability of the Ball Mill Bond’s Standard Test in a Ta Ore Due to the Lack of Standardization

Abstract

There is no doubt about the practical interest of Fred Bond’s methodology in the field of comminution, not only in tumbling mills design and operation but also in mineral raw materials grindability characterization. Increasing energy efficiency in comminution operations globally is considered a significant challenge involving several Sustainable Development Goals (SDGs). In particular, the Bond work index (wi) is considered a critical parameter at an industrial scale, provided that power consumption in comminution operations accounts for up to 40% of operational costs. Despite this, the variability of wi when performing the ball mill Bond’s standard test is not always understood enough. This study shows the results of a variability analysis (a 33 factorial design) performed to elucidate the influence on wi of several parameters obtained from the particle size distribution (PSD) in feed and product. Results showed a clear variability in the work and grindability indexes with some of the variables considered.

Keywords

• comminution
• grindability
• work index
• energy efficiency