| 摘要 |
PURPOSE:To reduce the sulfur content of reduced iron by maintaining a high- temperature reductive atmosphere for a fixed period of time even after the ending of reductive reaction while charging a reducing agent even from the outlet side of rotary kiln in the manufacture of reduced iron in the rotary kiln. CONSTITUTION:Powdered iron ore and a binder are pelletized together in a movable grading furnace 1, and then charged, together with a solid reducing agent 3 and a desulfurizer 4, into a rotary kiln 2. Even from the outlet of the rotary kiln, a powdered solid reducing agent 8 containing 3% or more volatile matters is blown into the kiln in an amout corresponding to 20% or more of the amount of the reducing agent to be charged from the inlet of the kiln, together with a carrier gas, by a blower 7 in such a way that the metallic transition of the iron ore pellets can reach 80% or more. A retaining zone for desulfurization is provided in a high-temperature and high-reducing atmosphere of outlet side portion corresponding to about 1/10 of the whole length of the rotary kiln, by which the S content of reduced iron is decreased to 0.03% or less. |
