EXTRACTION OF IRON
		INTRODUCTION
		Iron is extracted from its oxide	ore called HAEMATITE (Fe2O3).
		PRINCIPLE OF EXTRACTION
		Extraction of iron is based on the reduction of HAEMATITE (Fe2O3) with carbon..
		DETAILS OF EXTRACTION
		The process of the extraction of iron is carried out by the following steps:
		Concentration of ore Calcination or Roasting of ore Reduction of ore
		Concentration of ore: In this metallurgical operation, the ore is concentrated by removing impurities like soil etc. The process involves the crushing and washing of ore.
		Calcination or Roasting of ore: The concentrated ore is now heated in the presence of air. The process of roasting is performed to remove moisture, CO2, impurities of sulphur, arsenic. Ferrous oxide is also oxidized to ferric oxide.
		Reduction of ore
		The process of reduction is carried out in a blast furnace.
		Blast Furnace
		The blast furnace is a cylindrical tower like structure about 25m to 35m high. It has an outer shell of steel. Inside of furnace is lined with fire bricks. The top of the furnace is closed by a cup-cone feeder.
		The charge
		The charge consists of : roasted ore Coke Limestone
		Details of reduction
		The charge is fed into the furnace from its top. A preheated blast of air at 1500OC, is blown into the furnace under pressure near to the bottom. The blast oxidizes carbon to CO2.
		C + O2 CO2 + heat
		Formation of CO2 is an exothermic reaction in which a huge amount of heat is liberated which rises the temperature to 1900OC in this region. As the CO2 passes upwards, it reacts more coke to form carbon monoxide.
		CO2 + C 2CO + heat
		Formation of CO is an endothermic reaction and the temperature in this region falls to 1100OC. CO is the main reducing agent in the upper portion of blast furnace.
		Reactions in blast furnace
		Fe2O3 + 3C 2Fe + 3CO Fe3O4 + 4CO 3Fe + 4CO2 CO2 + C 2CO
		Overall reaction
		Fe2O3 + 3CO 2Fe + 3CO2
		The liquid iron runs downward to the bottom of the furnace and is withdrawn through tap hole.
		Slag formation
		Lime stone on heating decomposes to CaO and CO2.
		CaCO3 CaO + CO2
		CaO now reacts the impurities of ore called GANGUE to form slag. Slag is the mixture of CaSiO3 and Ca(AlO2)2. The slag floats over the top of molten iron. Slag is a useful byproduct. It is used in road making, cement manufacturing a light weight building materials.
		Flux + Gangue Slag            CaO + SiO2 CaSiO3     CaO + Al2O3 Ca(AlO2)2
	blust furnance