In countercurrent reaction device, in two step heating and refining should be able to effectively use the energy at a time. Primary energy smelting furnace (PEM) concept in the design of reaction device in this way, will be melting scrap steel from the top row in reaction device, by fossil fuel burning with oxygen, scrap into liquid from above liquidus temperature is reached.
In the furnace of independence, the electricity can not might well make molten steel overheating have solid materials. It can be an overview of the traditional electric furnace smelting process is separately according to time heating and melting scrap, and energy in a smelting process in these two steps, respectively in different space (the fire).