Capital Equipment News August 2022

CRUSHING

Trio cone crushers need to be choke fed to produce the best product shape and quality.

Maximising crusher efficiency

Knowing factors that affect a crusher’s efficiency can help operations improve their production rate. Speaking to Capital Equipment News , Theo Hendricks, product manager – comminution at Weir Minerals Africa, unpacks some of the key factors that affect the production efficiency of a crusher. By Munesu Shoko.

C rushing efficiency is key to production. Crushers, says Hendricks, form a vital part of the process flowsheet and are key to unlocking the valuable or sell able end product in the ore. Crushing is carried out to make the ore easier to handle between the different stages of the plant’s flow sheet. An inefficient crusher will therefore lead to an unbalanced plant. “Crushing progressively reduces the particle size of the ore until the valuable mineral can be successfully extracted by the relevant benefici ation methods. Not getting the specific particle sizes within specification – especially in the quar rying industry – results in revenue loss,” he says. Factors that affect crusher efficiency There are several factors that affect crusher efficiency. Firstly, says Hendricks, it’s important to consider ore properties such as hardness/ bondwork index, abrasion index, crushability and clay content. Based on these properties, one will be able to select the right type of crusher

and the relevant wear components that need to be installed in that particular crusher and application. For crushers, the most important wear item are the liners. “Moisture content is another important factor to consider. Higher moisture content in the ore may cause stickiness, which in turn results in pegging. The more the material sticks on the liners, the less efficient the crushing process becomes,” he says. The feed size range is another key factor that determines crushing efficiency. Jaw crushers, for example, operate efficiently with a correct feed size range. Bigger particles than what the crusher is designed to handle result in bridging in the crushing cavity, which reduces crushing efficiency. Unnecessary fines in the material also reduce the productivity of the crusher. More than 15% of fines in the cone crusher feed, for example, can cause ring bounce. Ideally, a cone crusher is preceded by a screen to ensure that the top and bottom sizes of the material to the crusher are correct. The crusher is also operated in

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