What is Coking Coal?
Steel is made from coke, also known as metallurgical coal. Coke is one of the most important inputs for steel production. In the world, there are many different types of coal, such as brown coal, lignite, and anthracite. It is the property of coking coals that sets them apart from other coals--they have the caking ability necessary to make coke suitable for steelmaking. A coke oven heats coke coals in a reducing atmosphere to produce coke. Coal becomes plastic when it is heated, fusing before resolidifying into coke particles. The process is known as caking.
What is Metallurgical Moal? How Does it Differ from the Other Types of Coal?
Metallurgical coal (or coking coal) is a sedimentary rock that occurs naturally in the earth's crust. Hard coking coal, semi-hard coking coal, semi-soft coking coal, and pulverized coal for injection are all types of met coal (PCI). These terms refer to the various grades of met coal that are used to create steel. Thermal coal, which is used to make power, has a higher carbon content, less ash, and less moisture than met coal.
What is the Purpose of Metallurgical Coal?
Steel manufacture requires metallurgical coal, which is one of the most commonly used building resources on the planet. One tonne of steel requires approximately 770 kilos of coal, with basic oxygen blast furnaces producing over 70% of world steel. The challenge for steelmaking is to produce this crucial commodity in a way that allows for long-term expansion while lowering the production process's greenhouse gas emissions. BHP expects to produce roughly 70 million tonnes of met coal in 2020. That's enough steel to construct the Burj Khalifa (the world's tallest structure) 1,600 times over!
(image will be uploaded soon)
What Methods are Used to Mine Metallurgical Coal?
Depending on how deep the coal is buried beneath the Earth's surface, several mining methods are used.
Underground
Coal is extracted by a longwall shearer deep below at our Broadmeadow mine in Central Queensland. On a conveyor belt, the coal is subsequently brought to the surface and stacked. At a coal handling and preparation factory, impurities are removed by washing and treatment. It is then carried to port by train, loaded into ships, and shipped to our customers.
Open Cut
We collect coal from seams that are relatively near to the surface in our open-cut mines. Excavators, draglines, shovels, and trucks are used to blast and remove the top layers of soil and rock to expose the coal, which is then mined with excavators, draglines, shovels, and trucks. After that, the coal is transferred to stockpiles. At a coal handling and preparation factory, impurities are removed by washing and treatment. It is then carried to port by train, loaded into ships, and shipped to our customers.
Coking Coal Meaning
Coke is a hard grey cellular material that softens and agglomerates when heated and after volatile stuff has been driven out at high temperatures. It is the meaning of coking coal. Coking coal is defined as coal of a quality that enables the creation of coke appropriate for use in blast furnaces. On an ash-free yet moist basis, it has a gross calorific value of more than 23 865kJ/kg (5 700 kcal/kg). It is the coking coal definition.
Uses of Coke Coal
Coke is mostly used as a fuel for stoves, furnaces, and blacksmithing. Because coke creates very little smoke, it is sometimes favoured over coal.
In a blast furnace, it's also used to make iron.
Coke is used to make steel and a range of other items as per the uses of coke coal.
Did You Know
The quality of the resulting coke is governed by the coking coals utilised and the working parameters of the coke plant. Coke quality is influenced mostly by coal rank, composition, mineral content, and the capacity to soften, become flexible and resolidify into a cohesive mass when heated. Coking coals are bituminous class coals with the high, medium, or low volatile ranks that have these qualities. Steel companies are in high demand for high-quality coking coals, which they need to make high-quality coke to increase the productivity of their blast furnace operations.
Even though metallurgical and thermal coal has the same origin, their economic markets and industrial applications are quite different.
FAQs on Coking coal
1. What is the need for coking coal?
As a reducing agent, coal is required. The chemical reaction "reduction" transforms iron ore (Fe2O3) into pig iron (2Fe). The key element (Fe2O3 + 3CO-> 2Fe + 3CO2) is carbon monoxide (CO), which is created in blast furnaces by burning coal. The product is carbon dioxide. Alternatively, hydrogen (H2) can be used as a reducing agent to create Direct-Reduced Iron (DRI) with only water as a waste product (Fe2O3 + 3H2 = 2Fe + 3H2O).
Unfortunately, most hydrogen gas is prepared using fossil fuels. There are energy-intensive alternatives, such as the electrolysis of water. However, if these activities were powered by renewable energy sources, there would be no greenhouse gas emissions.
2. Mention the use of Coking coal in the iron and steel industry?
Coking coal is a critical component of the iron and steel industry. The blast furnace and the generation of metallurgical coke for reduction of iron ore or injection with the hot blast are the two most common uses of coke coal in the steel industry. A lump of low-volatile hard coking coal with a high swelling index and strong fluidity makes up the majority of the export trade. Coal is used in more than 66 percent of steel production. In 2013, the world produced 1.6 billion tonnes of crude steel. Around 0.6 t (600 kilograms) of coke generates 1 t (1000 kg) of steel, implying that 770 kg of coal is needed in this process to produce 1 t of steel.
