Screen Efficiency
Calculate screen class recoveries and their product from a two-class dry balance; explicitly a recovery product, not undersize purity.
Description
Screen separation has two recoveries: fines to undersize and coarse particles to oversize.
Screen separation has two recoveries: fines to undersize and coarse particles to oversize. Their product is the combined efficiency convention used here.
The tool returns finesRecoveryFraction (fines recovery fraction); coarseRecoveryFraction (coarse recovery fraction); combinedSeparationEfficiency (combined separation efficiency). Input measurements and model parameters are supplied by the caller; the tool computes the stated summary rather than acquiring those measurements.
When to use Screen Efficiency
Use Screen Efficiency when you already have feedTonnesPerHour, feedUndersizeFraction, undersizeProductTonnesPerHour, undersizeProductFineFraction and want finesRecoveryFraction, coarseRecoveryFraction, combinedSeparationEfficiency. This is useful for checking a supplied calculation, documenting a measurement convention, or comparing observations prepared on the same basis.
How to use Screen Efficiency and understand its results
- Enter feedTonnesPerHour, feedUndersizeFraction, undersizeProductTonnesPerHour, undersizeProductFineFraction using the field table below. Match the units, ordering and data boundaries described in the calculation.
- Run the tool after checking the stated bounds and matching paired observations or categories. A malformed request gives a tool error rather than a usable measurement.
- Read finesRecoveryFraction, coarseRecoveryFraction, combinedSeparationEfficiency. Use the calculation and interpretation below to distinguish amounts, ratios, signs and decision flags where applicable.
- Review the supplied parameters and assumptions before using the result in a report or comparing it with another observation.
| Input field | Meaning | Value type and bounds | Requirement |
|---|---|---|---|
| feedTonnesPerHour | Feed tonnes per hour | number | Required |
| feedUndersizeFraction | Feed undersize fraction | number | Required |
| undersizeProductTonnesPerHour | Undersize product tonnes per hour | number | Required |
| undersizeProductFineFraction | Undersize product fine fraction | number | Required |
Require a feed containing both size classes and valid product fractions. Calculate component balances and reject recoveries outside [0,1].
fines recovery = undersizeFines/feedFines; coarse recovery = (feedCoarse−undersizeCoarse)/feedCoarse The symbols refer to the supplied quantities or generated values described above; unit conversions and comparison boundaries follow the stated implementation.
{
"input": {
"feedTonnesPerHour": 100,
"feedUndersizeFraction": 0.4,
"undersizeProductTonnesPerHour": 40,
"undersizeProductFineFraction": 0.9
},
"output": {
"finesRecoveryFraction": 0.9,
"coarseRecoveryFraction": 0.9333333333333333,
"combinedSeparationEfficiency": 0.8400000000000001
}
}Limitations and assumptions
This assumes a two-product size balance. The combined product is not interchangeable with total correctly placed mass percentage.
Numerical inputs must be finite. The tool checks its declared input shape and calculation constraints; those checks do not verify the quality, calibration or representativeness of the supplied observations.
Alternative or Complementary methods
Screen Capacity: Estimate screen capacity from caller area loading and correction factors; no vendor guarantee or calibration applicability is inferred. Tailings Grade: Solve residual tailings mass and assay from a closed dry feed/concentrate balance; impossible negative or above-one assays return errors.
Methodological background: Material balance in mineral processing.1
References
-
Material balance in mineral processing — NPTEL, Indian Institute of Technology Kanpur
Similar or alternative tools
- Screen Capacity
Estimate screen capacity from caller area loading and correction factors; no vendor guarantee or calibration applicability is inferred.
- Tailings Grade
Solve residual tailings mass and assay from a closed dry feed/concentrate balance; impossible negative or above-one assays return errors.