METHOD OF PRETREATING MATERIAL THAT IS FED INTO A SMELTING FURNACE, AND A PREHEATING SYSTEM

摘要

The invention relates to a method of pre-treating material that is fed into a smelting furnace (2), such as an electric furnace, whereby the feed material (5) is treated in a preheating system (1) comprising several separate preheating silos (3), each of them being connected, at the lower part thereof, to the smelting furnace by means of at least one feed pipe (6), the preheating system containing a means for distributing the heating gas in the preheating silo (3), whereby the gas mixture (4) that is fed into each preheating silo (3) of the preheating system is heated in a common gas heating unit (8), whereby the temperature of the material in each preheating silo (3) is adjusted by changing the amount of gas mixture (4) that is fed through the gas heating unit (8). The invention also relates to the preheating system.