Industrial Minerals & Powder Processing calculator
Particle Size Yield Calculator
Calculate the percentage of milled mineral product that falls within the target particle size specification after screening or air classification. Use it to monitor on-spec yield and decide whether classifier settings, screen media, or mill parameters need adjustment.
What this calculator does
- Calculate the percentage of milled mineral product that falls within the target particle size specification after screening or air classification.
- Use it when a quality manager or process engineer needs to track how much on-spec product the grinding and classification circuit is producing versus oversize rejects and fines losses.
- Shows what percentage of total production meets the target particle size specification and how far you are from the yield target.
Formula used
- Particle size yield = on-spec product tonnage / total production tonnage x 100
- Gap to target = particle size yield - target yield rate
Inputs explained
- On-spec product tonnage: Enter the tons of product that passed within the target particle size range (between the top cut and fines cut).
- Total production tonnage: Enter the total tons fed through the grinding and classification circuit during the same period.
- Target yield rate: Enter the minimum acceptable on-spec yield for the product grade. Typical targets range from 85% to 95% depending on mineral and specification.
How to use the result
- Use after screen analysis, sieve tests, or laser diffraction results to track classification performance over time.
- Results depend on feed size distribution, mill discharge fineness, classifier cut point, screen condition, aperture wear, blinding, moisture, and sampling accuracy. Validate product specifications with lab analysis and customer requirements.
Common questions
- What information do I need before using the Particle Size Yield calculator? You need the tons of on-spec product (within target mesh or micron range), total tons produced through the circuit, and your minimum acceptable yield percentage.
- What does the result mean? The result shows what percentage of your total milled output is meeting the particle size specification, and how many percentage points you are above or below your target.
- When is the result only an estimate? Always. Particle size distribution varies with feed hardness, mill condition, classifier settings, screen wear, moisture, and sampling method. Use lab sieve or laser analysis for final QC confirmation.
- What decision can I make from the result? Use it to adjust classifier speed or air volume, change screen media, schedule mill maintenance, rework oversize material, or justify grinding circuit improvements.
Last reviewed 2026-05-12.