The aluminium melting furnace operates on the principle of controlled combustion where fuel (natural gas, LPG, or diesel) is burned in a combustion chamber equipped with high-efficiency burners. The generated heat is transferred to the metal charge through radiation and convection. In crucible-type furnaces, the metal is contained in a graphite or silicon carbide crucible that is externally heated. In reverberatory designs, the flame directly impinges on the metal surface in a refractory-lined hearth. Temperature is precisely controlled using PID controllers with thermocouple sensors, maintaining the melt within the optimal range of 660-750 degrees Celsius for aluminium. Advanced models feature flue gas recirculation and recuperators to preheat combustion air, achieving thermal efficiencies exceeding 45%.