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Steel degassing processes require robust and reliable vacuum systems. Our vacuum equipment lets you build a sustainable steel degassing plant.
A steel degassing plant is a facility used in the production of high-quality steels. It is designed to remove elements such as carbon, hydrogen, oxygen, and nitrogen from the molten steel by a process known as vacuum degassing
During vacuum degassing the liquid steel is treated under vacuum which is created with a vacuum pump system.
The steel degassing process can have very specific requirements depending on the facility design, metallurgy routes, and desired quality of the final product.
Vacuum treatment of molten steel where a vacuum is applied in a special chamber - degasser with a ladle of molten steel inside. The typically targeted operation pressures range from 1.33 mbar (1 Torr) to 0,67 mbar (0.5 Torr)
Vacuum process where pure oxygen is blown onto the surface of the molten steel in a pressure range of 50-200 mbar. The carbon content of the steel is oxidized, converted towards a gaseous CO/CO2 mixture which is then evacuated via the vacuum system. Typically, after the rough vacuum VOD process step, a VD process at low pressure follows, combining these two steps inside the same degasser design
High productivity steel degassing process. The steel circulates inside a degassing chamberwhich is immersed into the steel ladle. Vacuum is used to lift up the steel into the degassing chamber and ensures the degassing itself (as in VD). The high circulation speed of the molten steel is ensured by an Argon flow into one of the suction snorkels. A RH-degasser can also be used for carbon reduction by blowing pure oxygen onto the circulating melt during a rough vacuum step, this is then called a RH(O) process.
The vacuum system is a critical component for the steel degassing process as it enables the creation and maintenance of the required vacuum level in the chamber. There are two rivalling types of vacuum solutions in steel degassing plants. Historically steam ejector vacuum systems (often with liquid ring vacuum pumps) are used while today mechanical vacuum systems consisting out of combinations or Roots blowers supported by dry screw vacuum pumps became a cost-saving and environmental friendly alternative.
Steel Degassing plants are mostly equipped with steam ejector pump systems. These have relative low CAPEX cost but require a massive amount of utilities like steam and water. Moreover, they create a huge amount of waste-water which need to be treated. The steam is mostly produced with a steam boiler powered by natural gas, which causes immense CO2 emissions.
Today’s need for energy savings, green transition and a carbon-emission free economy challenges the metallurgical industry massively. Every steel factory needs to develop the right strategy to survive on the market. To retrofit steam ejector systems with a mechanical vacuum system provides a solid step for the metallurgical industry to become more energy efficient and to emit less CO2.
Leybold can support this transition with our “full revamping” proposal, offering you advice such as:
Leybold is a market leader in providing vacuum systems for steel degassing. Our proven solutions can be integrated into the design of new Steel Degassing plants or retrofitted into existing degassers by our “full revamping” offering. We provide complete upgrade solutions for steel degassing plants to upgrade old-fashioned, energy inefficient steam ejector systems with modern, robust and efficient mechanical vacuum systems.