Aluminum scrap melting is a core link in secondary aluminum recycling, and the recovery rate directly determines production profits and resource utilization efficiency.
The main aluminum loss in melting production mainly comes from four key factors: oxidative burning loss, aluminum entrapment in slag, splashing & overflow, and uncollected fine dust materials.
Based on practical factory operation experience, I’ve sorted out the most cost-effective optimization strategies for improving aluminum recovery:
✅ Pre-Melting Raw Material Preprocessing (Low Cost, High Return)
Strictly sort impurities such as iron, plastic, sediment and coating materials to avoid hard slag wrapping molten aluminum. Classify thick aluminum materials, thin sheets, aluminum chips and die-casting residues separately. Compress loose aluminum chips and foils into blocks to greatly reduce air contact area and oxidative burning loss. Fully dry and deoil oily/wet scrap to prevent splashing and increased oxide slag.
✅ Scientific Melting Temperature & Operation Control
Control the optimal molten aluminum temperature at 720–760℃ and avoid long-term overheating above 780℃ (high temperature exponentially accelerates aluminum oxidation).
✅ Refining & Slag Discharging Standardization
Avoid excessive use of slag remover to prevent viscous slag from wrapping a large amount of metallic aluminum. Control slag skimming temperature at 700–730℃, and operate gently without stirring the molten aluminum, to minimize aluminum entrapment in slag.
✅ Secondary Recovery of Aluminum Slag (Core Profit Point)
Most aluminum loss is not from burning, but from un-recycled metallic aluminum in slag. Timely hot slag processing with a slag remelting machine can recover 40%–70% of free aluminum from ash and slag. Collect dust fine powder uniformly and return it to the furnace to avoid invisible material loss.
What’s the biggest factor restricting the aluminum recovery rate in your factory? Oxidation loss, slag entrapment or irregular operation? Drop a comment to exchange practical experience!
