Grinding has a significant impact on energy consumption in mining, as it is the most energy-intensive stage of mineral processing, often accounting for around 50% or more of a mine’s total energy use. Efficient grinding directly affects operating costs and the overall economic viability of mining operations.
Grinding energy consumption depends on feed and product particle size, wood type, moisture content, and grinding method. Different mills operate in specific size ranges, with cutter mills consuming 0.06–0.2 kWh/kg and vibration media mills achieving finer particles with lower energy use than refiners. Lab-scale mills often report higher energy consumption, such as 1.844 kWh/kg for grinding sawdust to 233 µm, indicating low energy efficiency. Many reported values lack optimization, highlighting the need for energy-efficient grinding technologies(Wang et al., 2018).
Energy consumption in grinding is influenced not only by the material’s properties and grinder type but also by the energy supply method and loading conditions. The grinding equipment determines how energy is delivered and dissipated through mechanisms like friction and fluid viscosity. As materials are ground, they become more cohesive and resistant due to reduced particle size, requiring energy to overcome both inter- and intra-particle forces. Particularly in fine grinding, this results in very low energy efficiency with only 4% to 8% of the input energy actually used to create new surfaces(Understanding the Operation of Grinding Mills in the Mining and Mineral Processing Industry – NEWS – SMMVIK Machinery, n.d.).
Why is the single most energy-intensive process in mining also the least efficient?
Reference:
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Understanding the operation of grinding mills in the mining and mineral processing industry—NEWS – SMMVIK Machinery. (n.d.). Retrieved September 17, 2025, from https://www.millvik.com/news/understanding-the-operation-of-grinding.html
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Wang, J., Gao, J., Brandt, K. L., & Wolcott, M. P. (2018). Energy consumption of two-stage fine grinding of Douglas-fir wood. Journal of Wood Science, 64(4), 338–346. https://doi.org/10.1007/s10086-018-1712-1
