Iron Ore and Coal

 

Coal is a hard black mineral which is burnt to produce heat and coke is a solid black carbonaceous substance with few impurities and high carbon content, usually made from coal. It is derived from destructive of low-ash, low-sulfur bituminous coal as well.
The use of coke is for reducing factors in smelting iron ore in a blast furnace and it is also used as a fuel. In the production of the iron product, the carbon monoxide produced by its burning reduces iron oxide (hematite).
In today’s life, steel is a kind of necessary material which has a lot of uses – in healthcare, telecommunications, agricultures, transporting networks, clean water, and access to reliable and affordable energy and so forth. However, the Global steel production is dependent on coal. Nowadays, 70% of the steel production uses coal. A vital ingredient in the steel making process is Metallurgical coal or coking coal. About 721 million tonnes of coking coal was used in the production of steel. Besides, in 2010 the World crude steel production was 1.4 billion tones.


Steel

Steel is an alloy based on iron. As iron occurs only as iron oxides in the earth’s crust, the ores must be converted, or ‘reduced’, using carbon. The first source of this carbon is coking coal.

Coke and Iron Making

The process of coke making is to leave pure carbon by driving off the impurities. Almost all metallurgical coal is used in coke ovens. Moreover, coking coal must have low sulfur and phosphorous elements too.
The coking process includes heating coking coal to around 1000-1100ºC to drive off the volatile compounds in the absence of oxygen. This process takes a long time about 12 to 36 hours in the coke ovens. Then it is quenched with either water or air to cool it before storage or is transferred directly to the blast furnace for use in iron making.
About 50 countries mining the Iron ore but the biggest producers are Australia, Brazil and China and around 98% of iron ore is used in steel-making. During iron making process, a blast furnace is fed with the iron ore, coke and small quantities of fluxes (minerals, such as limestone, which are used to collect impurities). Air which is heated to about 1200°C is blown into the furnace through nozzles in the lower section. The air makes the coke to burn, producing carbon monoxide which reacts with the iron ore, as well as heat to melt the iron. Eventually, the molten iron and other impurities (slag) are drained off at the bottom of the furnace.