
Size Reduction Equipment
WORK INDEX •Work Index, Wi, is the gross energy requirement in kilowatt hour per ton of feed (kWh/ton of feed) to reduce a very large particle to such a size that 80% of the product will pass through a 10micrometer, or mm screen. •If Dp is in mm, 𝑊𝑖=𝐾 1 𝐷𝑝𝑝 𝐾 = 𝑊𝑖=𝑊𝑖 I =𝑊𝑖 1 𝑝𝑝 − 1 𝑝 .