In an iron blast furnace, raw materials are charged from the top.
The major raw materials are:
\[
\text{iron ore, coke, and limestone}
\]
These materials must be lifted to the furnace top.
A skip hoist is commonly used for this purpose.
A skip hoist consists of skip cars moving on an inclined track.
The skip carries the charge materials to the top of the blast furnace.
Then the materials are discharged into the furnace charging system.
Bucket elevators and belt conveyors are used in other material handling operations.
Screw conveyors are generally used for short-distance movement of powdered or granular solids.
Therefore, raw materials are charged in the iron blast furnace using:
\[
\text{Skip hoist}
\]