The blast furnace is a large steel tower lined with refractory brick used to reduce and convert iron oxides into liquid iron. Iron ore, coke and limestone are continuously fed into the top of the blast furnace while preheated air is blown into the bottom. Inside the blast furnace, the coke reacts with oxygen in the air to produce carbon dioxide and later carbon monoxide, which reduces the iron ore to molten iron. The molten iron and slag are drained from the bottom while waste gases exit from the top.

1. Blast Furnace

2. Content
Blast Furnace
Structure and
Components of Blast
Furnace
2.0
Reactions & Summary
Reactions involved in
the Blast Furnace and
overview of the process
3.0
Introduction
Introduction about the
Blast Furnace
1.0

3. Introduction
● The purpose of a blast furnace is to reduce and convert
iron oxides into liquid iron called "hot metal".
● The blast furnace is a huge, steel stack lined with
refractory brick.
● Iron ore, coke and limestone are put into the top, and
preheated air is blown into the bottom.

4. Blast Furnace
● It is a tall cylindrical furnace made
of steel.
● It is lined inside with fire bricks.
● It is narrow at the top and has an
arrangement for the introduction
of ore and an outlet for waste
gases.
● Heated with the help of Hot Gases.

5. Blast Furnace
The outer case is a water-cooled
steel casing that provides the
main support for the 30 m high
furnace

6. Blast Furnace
● The sinter is added through a
hopper at the top of the Blast
Furnace.
● The design of the hopper stops
gases from escaping through
the top as sinter is added.

7. Blast Furnace
● The inner lining is made of
insulating bricks, designed to
reduce heat loss through the outer
walls of the furnace

8. Blast Furnace
● The furnace is run continuously
for up to 2 years.
● Air is blasted in at the bottom at
point A

9. Blast Furnace
● When running continuously, iron
is run out through a tap hole,
drilled into the furnace at the
bottom, B.

10. Blast Furnace
● Slag is less dense than iron and
floats on the surface.
● Slag is run out through a second
tap hole labeled C.

11. Blast Furnace
● Wasted gases pass out through the
top of the furnace, at point D.
● The hot gases are used to pre-heat
the incoming gases at A.

12. Blast Furnace
● Iron that forms in the furnace
melts at the temperature of
1700°C.
● The iron drips down to the bottom.

13. Summary
Step 1 - Insert iron ore, limestone, and coke into blast furnace.
Step 2 - Coke reacts with oxygen and forms carbon dioxide.
Step 3 - Carbon dioxide produced in the first 2 reactions reacts
with excess coke and forms carbon monoxide.

14. Summary
Step 4 - Carbon monoxide reduces iron ore and produces molten
iron.
Step 5 - The excess limestone from the second reaction reacts
with the sand (coming from minerals in iron ore) and forms
calcium silicate (slag) .
Step 6 - Slag and molten iron are drained from the bottom of the
furnace and gas produced exits through holes in the top of the
furnace.

15. Products Formed
● Both the slag and iron are drained from the bottom of
the furnace.
● The slag is mainly used to build roads.
● The iron whilst molten is poured into molds and left to
solidify - this is called cast iron and is used to make
railings and storage tanks.
● The rest of the iron is used to make steel.

16. Thank You