American aluminum industry hot innovation technology - isothermal aluminum melting technology

Isothermal Melting (ITM) is a smelting system that uses an electric submergence heater that is heated by heat conduction. This system converts 97% of the electric energy into heat. "Isothermal smelting" means that the temperature is kept constant, that is, the temperature in each location in the molten pool is basically the same. The use of this technology eliminates the disadvantages of high gas temperature and energy waste due to the use of heat radiation to smelt metals in conventional gas burners. At present, the vast majority of metallic aluminum is smelted in a gas furnace with low thermal efficiency (about 30%). In the United States, the annual production of ingots, sheets, slabs, extrusions, and castings requires smelting of 14.52 million tons of aluminum and energy consumption of approximately 196.3 billion kilowatt-hours. When melting in a gas smelting furnace, the energy consumption is 1.35 kWh/kg, and the metal oxidation loss is 2%-4%. With isothermal smelting technology, the energy consumption of smelted aluminum can be reduced to 0.42 kWh/kg, and the oxidative loss can be reduced to <1%. Isothermal smelting technology can be predicted to save 50% energy, reduce emissions by 80%, and save a lot of metal. By 2020, if the aluminum industry in the United States uses 60% of the smelting equipment, the nation can save 54.5 billion kWh and reduce equivalent carbon dioxide emissions by 180,000 tons. Why isothermal melting technology has such high energy-saving efficiency? The key is that the isothermal smelting system is a multi-slot design and uses an immersed heater. Each slot plays a role in improving efficiency. The suction tank promotes good circulation of the entire system. This circulation improves the purity of the metal, makes the mixing of the alloying elements more uniform and makes the temperature in the bath more uniform. Heating tanks are the main source of energy. In this tank, electrical energy is converted into thermal energy by the immersed heater and passed directly to the molten metal. Heating the tank by raising the temperature of the molten metal by 90°F is sufficient to melt the solid metal that fills the tank. Filling tanks and treatment tanks control the filling of solid materials, or alloying and purification processes are carried out in multiple small areas. Compared to conventional gas combustion furnaces, open furnace doors expose the entire pool surface and refractory materials to the atmosphere of the factory atmosphere. in.