STACK
Stack is cone like structure mounted on the mantle. It extends to the top of furnace. The furnace top is called Bell. The Bell, the charging arrangements and the gas offtakes
are mounted on top of the stack. The stack is made of welded steel plates with inner fire brick linings.
BUSTLE PIPE
Bustle pipe is a huge circular pipe through which hot blasts from the stoves are supplied to the furnace .It is circular and encircles the furnace at the bosh level.
The tuyeres are connected to the bustle pipe.
HOT BLAST SUPPLY EQUIPMENT
Air blast is preheated to a temperature of 700-1200 'C in Cowper regenerator stoves. A set of 3/4 regenerators is provided for each furnace. The stove is 6-9 m
in diameter and 30-35m in height. Special thin walled bricks are used for construction of checker-works in the stove.
OFFTAKES
Offtakes are exhaust pipes that are connected to the furnace top. A single chimney is connected to these offtakes for release of exhaust gases. Nowadays
these offtakes are connected to gas cleaning plants for reuse of hot gas after proper cleaning. The hot gas is used after proper cleaning in the air blast or in the captive power plant.
GAS CLEANING SYSTEM
The blast furnace gas is cleaned properly before its reuse as a fuel. The dust catcher is used to separate dust particles from the exhaust gas. The cleaned gas is
passed through scrubbers & electrostatic precipitators. After the gas is completely cleaned, it is used as air blast. If there is excess of gas, then the remaining gas
may be used in power plants.
RAW MATERIALS STORAGE AND HANDLING
To produce 1 tone of pig iron, nearly 3 tons of iron ore, coke and limestone as solid charged materials are used in the furnace. The furnace is successfully run if the
raw material supply is regular and continuous. Sufficient reserve stock of raw materials near the furnace is required for continuous production of hot metal. Large storage
facility in the form of yard and storage bins is provided near the blast furnace for storage of raw material. Efficient charging and weighing facilities are provided for smooth
operation of the plant.
LIQUID PRODUCTS MANAGEMENT
Liquid product like molten iron and liquid slag are generated in the blast furnace. The slag is formed due to reaction of lime stone with silicates and other impurities present
in the iron ore. The liquid slag floats over the molten metal as thin layer. The slag is removed from the furnace through a tapping hole. The molten metal settles down at the bottom
and separated out through tap holes provided at the bottom of furnace.