Industrial Minerals & Powder Processing worked example

Grinding Mill Throughput at 98% mill operating efficiency: a worked example

Push mill operating efficiency up to 98% and the picture changes. This example computes every intermediate figure at that operating point. Use it when a mill operator or process engineer needs to verify whether a grinding circuit can sustain the required tons per hour before committing a production schedule or capital upgrade.

The inputs for this scenario

  • Finished milled output: 80 tons (unchanged)
  • Productive mill runtime: 8 hr (unchanged)
  • Mill operating efficiency: 98 % (raised for this scenario; the documented default is 85)

Working through the calculation

  • Applying the documented formula (Raw mill throughput = finished milled output / productive mill runtime) to the inputs above produces each figure below.
  • At this operating point the engine returns 9.8 tons / hr for effective throughput, the number this scenario is built around.
  • At this operating point the engine returns 10 tons / hr for raw mill throughput.
  • At this operating point the engine returns 98 % for efficiency.
  • At this operating point the engine returns 8 hr for runtime.

How this compares with the baseline

  • Against the tool's baseline example, where mill operating efficiency sits at 85% and the headline result is 8.5 tons / hr, this scenario comes in 15.29% above the baseline at 9.8 tons / hr.
  • It converts finished milled tonnage and productive runtime into a raw rate, then discounts it by operating efficiency to give effective tons per hour. The value of this scenario is the size of the gap it exposes: that gap, priced out over a year, is the budget you can justify spending to close it.

Results at a glance

  • Effective throughput: 9.8 tons / hr (headline result)
  • Raw mill throughput: 10 tons / hr
  • Efficiency: 98 %
  • Runtime: 8 hr

Run it with your numbers

  • Every input above is editable in the live Grinding Mill Throughput calculator, which recalculates instantly and can be shared with the inputs intact.

Last reviewed 2026-05-12.