Primary steelmaking involves converting liquid iron from blowing oxygen in the blast furnace. It lowers the carbon content of the alloy and changes it's chemistry ensuring that the impurities such as sulphur and phosphorus are removed.
Secondary steel is made after addition of ferroalloys and other elements to the ladle to perform metallurgical operations to produce high grades of steel in which the tolerances in chemistry is consistent
Cement specially formulated with unique binding properties designed to provide high strength. It’s characteristics are standardised in order to ensure the required stability and reliability.