| 摘要 |
PURPOSE:To reduce the content of Si in pig iron effectively by blowing iron oxide or reduced iron together with pulverized coal into a blast furnace through a blast tuyere. CONSTITUTION:Pulverized coal is supplied from a raw material hopper 4 through an intermediate tank 5 into a transport pipe 10 by a pressure feed tank 6, and is blown into a blast furnace 1 through a blowing nozzle 11. At the same time, iron oxide or reduced iron is blown from the hopper 7 into the furnace through the nozzle 11 of the tuyere 3 via an intermediate tank 8, a pressure feed tank 9, and the pipe 10. The iron oxide or reduced iron to be used are ground in such a way that the contents of fine particles of about <=100meshes are similarly as the pulverized coal about >=50% and the rate of its blowing is set at about 5-50kg per ton of pig iron while the ordinary rate of blowing of the pulverized coal is about 30-150kg. Thereby, the Si% of the pig iron is reduced promptly without changing the other operation conditions of the blast furnace 1. |
