Energy Trends
Advances in Fine Grinding and ClassificationSummary: In the ore-processing sector, ball mills are increasingly being replaced by more energy-efficient grinding processes. This trend commenced in the regrinding of flotation products, progressed into the tertiary grinding stage and is now also changing the technology of secondary grinding. Furthermore, advances are also taking place in classification processes. This article describes the new processes and discusses the potential that they offer.
1 Introduction
Available resource deposits with a high content of useful minerals are becoming scarcer and scarcer. As a rule, the resources mined today can be described as finely and extremely finely intergrown ores. They require ore liberation to a size of 50 µm (0.05 mm) or even much finer. This particularly applies to polymetallic deposits with a complex composition. Such ores correspondingly require a comparatively high degree of processing effort. A large proportion of the operating expense for processing plants is accounted for by the crushing and grinding processes. The costs for ore...