| 摘要 |
PURPOSE:To economically manufacture pig iron under efficient good reduction, heat and plant utilization, by a method wherein powdery materials and fuels are charged from the upper part of shaft furnace, constant temperature indirect reduction zone being formed in furnace and the furnace top pressure is raised by feeding high concentration oxygen from tuyeres at the lower part of furnace. CONSTITUTION:Powdery coal 1 and powdery iron ore 2 are respectively fed to the hopper 5 provided at the top part of shaft furnace 8 by a charging conveyor 4 via weighing hoppers 3. Then, they are fed into the furnace 8 via a value seat 6 and a bell 7, and the high concentration oxygen from an oxygen source 9 is fed thereto through ordinary twyeres 11. At the same time, the indirect reducing zone consisting of a constant temperature zone of 600-1,100 deg.C is formed in the furnace 8 by injecting high concentration oxygen from the oxygen injecting tuyeres 10 provided at plural positions of upper level and the reduction of powdery iron ore 2 is carried out. At that time, the pressure in furnace is raised to about 2kg/cm<2> and the volume of generated gas is reduced. |
