What is desulphurization in steel making?
The principle of desulphurization is to transfer the sulfur dissolved in the liquid steel to a CaO-rich slag phase. The slag must take up a large amount of S from the liquid steel (have a “high sulfur capacity”) so that a significant amount of sulfur will move from the liquid steel to the slag phase.
How is sulphur removed from steel?
There are four stages where sulphur can be removed: in the blast furnace (BF), during hot metal (HM) pretreatment, in the converter and during the secondary metallurgy (SM) treatment. For low sulphur concentrations SM desulphurisation, with a decreased oxygen activity and a basic slag, is always required.
What is desulphurization process?
Desulfurization refers to the industrial process of removing sulfur from a mineral resource mixture such as crude oil. It predominantly involves a gas-purification industrial procedure used to remove hydrogen sulfide (H2S) and carbon dioxide (CO2) from a given mineral resource.
How is phosphorus removed from 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.
Why is desulphurization important?
These processes are of great industrial and environmental importance as they provide the bulk of sulfur used in industry (Claus process and Contact process), sulfur-free compounds that could otherwise not be used in a great number of catalytic processes, and also reduce the release of harmful sulfur compounds into the …
What are the favorable conditions for desulphurization?
The high temperature and low oxygen potential in hot metal after tapping from the BF provides a favourable condition for hot metal desulphurization. Removal of sulphur from the hot metal is called desulphurization of hot metal.
What is the role of Sulphur in steel?
Sulfur. Sulfur is usually an undesirable impurity in steel rather than an alloying element. In amounts exceeding 0.05% it tends to cause brittleness and reduce weldability. Alloying additions of sulfur in amounts from 0.10% to 0.30% will tend to improve the machinability of a steel.
What is the importance of desulphurization?
What is petroleum desulphurization?
Desulfurization is the process of removing sulfur from crude oil (or its fractions). It prevents contamination and also improves the efficiency of petroleum. Desulfurization removes elemental sulfur and its compounds from solids, liquids and gases.
How is phosphorus made into steel?
Phosphorus is one of the most potent solid solution strengtheners of ferrite. Hence, small additions of phosphorus are used to inexpensively increase the strength of low carbon sheet steel. Figure 1 compares the change in lower yield strength of carbon steel as a function of alloy addition for several common elements.
How does Decarburization occur?
Decarburization occurs when metals are subjected to high temperatures, and the carbon present on the surface reacts with oxygen or hydrogen and diffuses. The reaction between carbon and the atmospheric gases usually begins around 700°C (1292°F).
What is desulphurization of coal?
Some methods have been applied to coal to remove its inorganic materials from the organic part. Most of the effective coal desulfurization techniques are based on chemical methods. Main desulfurization methods are chemical desulfurization, leaching, extraction, flotation, oxydesulfuriza- tion and biodesulfurization.