How do you reduce phosphorus in steel?
The method entails melting a prepared slag in a separate furnace and tapping into the ladle before steel tapping. The induction furnace steel is then tapped onto this slag. The rapid mixing of the slag with the steel during tapping completes the removal of phosphorus even while tapping is going on.
How is phosphorus oxide removed from molten iron?
In a typical dephosphorization process, phosphorus present in hot metal or molten steel is oxidized with oxygen gas or iron oxide and the phosphorus oxide is removed by being trapped in CaO-based slag. The oxidation of phosphorus in hot metal or molten steel with oxygen gas also oxidizes iron.
What are the three basic steelmaking processes?
Of the three major steelmaking processes—basic oxygen, open hearth, and electric arc—the first two, with few exceptions, use liquid blast-furnace iron and scrap as raw material and the latter uses a solid charge of scrap and DRI.
What is steelmaking process?
Steelmaking is the process of producing steel from iron ore and/or scrap. Oxygen steelmaking is fueled predominantly by the exothermic nature of the reactions inside the vessel; in contrast, in EAF steelmaking, electrical energy is used to melt the solid scrap and/or DRI materials.
What is TBM in steel making?
In order to improve the quality of steel, Thyssen Bottom Metallurgy (TBM) technology is used. The TBM process was developed at ThyssenKrupp Stahl AG oxygen steelmaking shops. Products range from plain low carbon steels to sophisticated alloyed grades.
What is Dephosphorization process?
The dephosphorization processes (reduction in the phosphorus content) of pig iron consist in oxidizing the phosphorus and combining it with calcium and other components, which are injected into the hot metal deeply, resulting in compounds which are transferred to the slag and, thus, removed from the metal.
How is phosphorus removed from iron?
Acid leaching is the most efficient method for removal of phosphorus from iron ore. Among the tested acids, sulfuric acid is the most effective for this purpose. The leaching time is low (~20 minutes) and the iron loss is negligible (less than 0.25%).
What are the ores of phosphorus?
The major components of phosphate ores are the apatite phosphate minerals, the most common of which are fluorapatite (in endogenous apatite deposits) and carbonate apatite and its modifications, francolite and kurskite (in exogenous phosphorite deposits); hydroxylapatite sometimes occurs in significant amounts.
What is basicity in steel?
(in metallurgy), the ratio (in percent by weight) of basic and acidic oxides in iron ore materials (iron ore, sinter, and pellets), and also in blast-furnace and steel-smelting slag. Basicity defines the chemical composition and metallurgical properties of such materials.
Which furnace is used for refining steel?
electric arc furnace
BOFS and electric arc furnace slag (EAFS) are produced in basic oxygen furnace and electric arc furnace respectively, which are the most widely used processes for the steel manufacturing.
What is the Bessemer technique?
The Bessemer process was the first inexpensive industrial process for the mass production of steel from molten pig iron before the development of the open hearth furnace. The key principle is removal of impurities from the iron by oxidation with air being blown through the molten iron.
What is Dephosphorization of steel?
Dephosphorization of steels has become a very important metallurgical technique in steelmaking process to produce high quality steels. The content of P in liquid steel during tapping, deoxidation, inert gas blowing, and casting can increase gradually due to its introduction with deoxidizers and reduction from a slag.