When it comes to steel companies, the coal and iron mining are done by some of the same companies that create finished products from steel. These are all inclusive companies right from the get-go.
The Processing of Steel
Sinter and pellet processes are applied to the ore, while the coal is processed differently, upon receipt of the mined products. The ore starts out as more or less ‘sludge’ than anything else and after water removal is sent further up the processing line. Little pellets will be formed from the dried sludge after mixing with several other elements. These pellets go through a type of baking process and are then sent off to a blast furnace. Coal in the meantime, is made into coke and coke is the fuel for the blast furnaces. The gas that comes off of this coking process is saved and will be used later, down the line. There is in fact very little waste when it comes to the manufacture of steel. A product called pig iron is the result of the combining of various elements and the heat from the blasting furnace. 1650°C is a lot of blasting!
Is It Hot in Here or Is It Just Me?
The molten metal is drained and then poured into individual capacities of approximately 200 tons. The molten metal resembles hot, thick, lava like fluid – a result of the excessive heating process. This pig iron then enters a desulfurization plant. A resulting byproduct called slag is dumped into a pit, cooled with water, dried and then sold as a separate material. A BOF, basic oxygen furnace, is used to turn the pig iron into actual steel. Scrap metal is also used in this process. This combination is subjected to a pressurized mix from which liquid steel is finally obtained.
This is of course highly simplified for the sake of being brief, but you now have the basics of steel manufacturing. Steel is one of the most recycled materials being used today.