Title

DEVELOPMENT OF THE L.B.E. - PROCESS

DEVELOPMENT OF THE L.B.E. - PROCESS

Authorship

SCHLEIMER, FRANCIS; HENRION, ROMAIN; GOEDERT, FERDINAND; DENIER, GUY; GROSJEAN, JEANCLAUDE

SCHLEIMER, FRANCIS

I am this author

HENRION, ROMAIN

I am this author

GOEDERT, FERDINAND

I am this author

DENIER, GUY

I am this author

GROSJEAN, JEANCLAUDE

I am this author

DOI

10.5151/2594-5300-13Aciaria-343-368

Downloads

Abstract

Since 1975, the technique of bottom inert gas injection has been tested independently by IRSID on a 6 tons pilot converter and on a 65 tons LD converter (Usinor-Denain) for low phosphorus hot metal and by ARBED on two 150 tons LD-AC converters for high phosphorus hot metal. Permeable elements set in the bottom of the converter allow an inert gas to be blown through the melt during and after the oxygen blow. The large number of heats performed demonstrated that this new process extends considerably the capabilities of the vertical lance converter by gathering the advantages of both top and bottom oxygen blowing processes. The new process, called L.B.E. (Lance-Bubbling-Equilibrium), decreases the disequilibrium between the different phases in the converter. Trials demonstrated major beneficial effects: improved postcombustion of CO into CO₂ increasing scrap melting capacity without productivity loss; improved control of the blow by modulation of inert gas flowrate; decrease of phosphorus, sulphur and dissolved oxygen content; and deep decarburization without excessive bath oxidation. Industrial trials showed increased scrap input, improved iron yield, reduction in flux and ferro-alloy consumption, better slag control, improved steel quality, and extended refractory life. Additional inert gas injection after oxygen blowing further enhances dephosphorization, desulphurization and deoxidation. The LBE process is industrially applied in several European and North-American steel plants and commercialized jointly by ARBED and IRSID.

Since 1975, the technique of bottom inert gas injection has been tested independently by IRSID on a 6 tons pilot converter and on a 65 tons LD converter (Usinor-Denain) for low phosphorus hot metal and by ARBED on two 150 tons LD-AC converters for high phosphorus hot metal. Permeable elements set in the bottom of the converter allow an inert gas to be blown through the melt during and after the oxygen blow. The large number of heats performed demonstrated that this new process extends considerably the capabilities of the vertical lance converter by gathering the advantages of both top and bottom oxygen blowing processes. The new process, called L.B.E. (Lance-Bubbling-Equilibrium), decreases the disequilibrium between the different phases in the converter. Trials demonstrated major beneficial effects: improved postcombustion of CO into CO₂ increasing scrap melting capacity without productivity loss; improved control of the blow by modulation of inert gas flowrate; decrease of phosphorus, sulphur and dissolved oxygen content; and deep decarburization without excessive bath oxidation. Industrial trials showed increased scrap input, improved iron yield, reduction in flux and ferro-alloy consumption, better slag control, improved steel quality, and extended refractory life. Additional inert gas injection after oxygen blowing further enhances dephosphorization, desulphurization and deoxidation. The LBE process is industrially applied in several European and North-American steel plants and commercialized jointly by ARBED and IRSID.

Keywords

LBE process, Bottom inert gas injection, LD converter, Steelmaking, Decarburization

LBE process, Bottom inert gas injection, LD converter, Steelmaking, Decarburization