Recovery (or yield) is the weight of clean metal tapped from the furnace divided by the weight of material charged, expressed as a percentage. The difference is melt loss: oxidation, dross formation, burnt coatings, moisture, oil, dirt and non-aluminium attachments. Thick, clean solids such as extrusion offcuts recover very well; thin, coated or oily material such as UBC or turnings recovers less; dross recovery depends on its metal content.
Why it matters when buying
- Two lots at the same rate per kg can have very different real costs if their recovery differs; compare on cost per kg of metal recovered.
- Agree how recovery will be tested: a trial melt of a representative sample is more reliable than a visual estimate.
- Check contamination, moisture and oil, which cut yield and can be dangerous in the furnace.
- For dross, buyers quote on metal content %, so ask how it was measured.
Notes
Furnace type, fluxing and charge practice also affect yield, so a buyer and seller may record different figures for the same lot. The guide how to check aluminium scrap recovery explains sampling and test melts.