The impact of hot metal temperature on CO2 emissions from basic oxygen converter

Recycled steel is a key material for sustainable development. However, not all steel demand can be met by recycling, and therefore new metallic iron must be introduced in the global cycle. The transformation of iron oxides into steel requires carbon which is oxidized into CO2. This paper focuses on the basic oxygen furnace (BOF) where molten iron is transformed into liquid steel. The process is modelled using mass and energy balances in order to assess the effect of molten iron temperature on CO2 emissions. Model results show that, for a typical converter charge, a slight change of 10 °C in the hot metal temperature can led to a direct variation of 0.01 t of CO2 per ton of liquid steel. Finally, different actuation levers for carbon mitigation are suggested. It can be concluded that operation and modelling improvements should be jointly addressed to exploit their full potential for carbon footprint reduction.

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Numerical Analysis of Multiphase Flow in a Steel Oxygen Converter With Top and Bottom Blowing

Volume 12: New Developments in Simulation Methods and Software for Engineering Applications ◽

10.1115/imece2007-42670 ◽

2007 ◽

Cited By ~ 1

Author(s):

Dulce Y. Medina ◽

Miguel A. Barron ◽

Isaias Hilerio

Keyword(s):

Multiphase Flow ◽

Oxygen Converter ◽

Metal Bath ◽

Decarburization Rate ◽

Basic Oxygen ◽

Basic Oxygen Converter ◽

Removal Of Impurities ◽

Bottom Blowing ◽

Bottom Injection ◽

Jet Velocities

Combined blowing in the steelmaking basic oxygen converter is a technique that allows more agitation in the metal bath, and gives a fast decarburization rate, accelerated removal of impurities and chemical and thermal homogenization. In this work the multiphase flow in an industrial-like basic oxygen converter with top and bottom blowing is analyzed by means of Computational Fluid Dynamics software. Turbulence in the converter is simulated by means of the classical K-ε model given that this model yields more numerical stability during the integration for long times. Top jet velocities of Mach 1 and Mach 2, and 50 and 100 m s−1 of bottom injection velocities are used, and the results are compared with the conventional top blowing injection. Numerical results show that the combined blowing generates more agitation of the metal bath than that of the top blowing, however, from an operating viewpoint, combined blowing promotes that a significant volume of molten metal be expelled from the converter mouth.

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Isothermal Experimental Study on the Effects of Converter Bath Shape on the Melt Mixing

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.402.100 ◽

2011 ◽

Vol 402 ◽

pp. 100-106

Author(s):

Jian Feng Duan ◽

Da Qiang Cang ◽

Ling Ling Zhang ◽

Dong Xu ◽

Li Xue Qin

Keyword(s):

Oxygen Converter ◽

Orthogonal Design ◽

Mixing Time ◽

Water Model ◽

Bath Surface ◽

Oxygen Lance ◽

Melt Mixing ◽

Basic Oxygen ◽

Basic Oxygen Converter ◽

Stirring Effect

The effects of the bath shape, oxygen lance nozzles structure, and lance level on liquid steel mixing time and splashing amount were studied by experiment orthogonal design with 1:10 water model for 100 t basic oxygen converter modeling. The results showed that the stirring effect in the bath can be improved by changing the shape on the bath surface around the furnace wall with arc-shaped structure which can shorten the mixing time and reduce the liquid slag and steel splashing amount of the lining, and result in reducing metal lose and prolong the life of the lining.

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