scholarly journals Energy efficient solutions of DC Electric Arc Furnace Bottom Electrode

2020 ◽  
pp. 121-129
Author(s):  
Sergii Timoshenko ◽  
Mikhail Gubinskij
Keyword(s):  
Phase Transition ◽  
Heat Flux ◽  
Transition Zone ◽  
Energy Efficient ◽  
Bottom Electrode ◽  
Thermal State ◽  
Steel Part ◽  
Electric Arc ◽  
Arc Furnace ◽  
Equilibrium Thickness

Analysis of recent research and publications. The problems of thermal state of billet-type bottom electrode (BE) in liquid bath of DC electric arc furnace (EAF) are associated with limited thermal conductivity of the rod in the absence of available alternative to copper-steel pair. There isn’t enough data on values of convective and Joule components of heat flux, passing through BE, initiated by electrovortex flows (EVF); regarding influence of thermophysical characteristics of transition copper-steel zone and cooling rate of BE copper part on the position of phase transition surface of steel part. Problems are considered, especially related to innovative “flat bath” steelmaking technologies, in which the possibilities of dead time pauses for periodic renewal of the BE body due to “EVF-off” are significantly limited.Purpose. To investigate the effect of EVT on the thermal state of bottom electrode and to develop on this base the energy efficient BE solutions.Methodology. Numerical simulations of BE thermal state and an industrial testing of essentials. Findings & Originality. For the first time, the joint effect of EVF, Joule heat, and characteristics of BE transition zone copper – steel on the position and equilibrium thickness of solid steel part of the BE, which determines the energy efficiency of DC EAF operation, was comprehensively studied.Research implications. Numerical simulations of EVF in DC EAF steelmaking bath and heat transfer with a phase transition through BE were carried out. The heat flux density and local EVF velocity in anode well are 1.8–2 MW/m2 and 0.75 m/s, respectively. Equilibrium thickness of solid steel BE part is critically dependent on the width of copper-steel transition zone, should not exceed 20-25 mm. Contribution of Joule component of total thermal load on the BE does not exceed 20%. Intensification of cooling rate above ≥ 20 kW/(m2K) practically doesn’t affect the BE solid steel part thickness.Practical implications. Manufacturing technology of BE with a narrow transition zone by the method of two-stage electro-slag welding of copper on a steel billet, which ensures stable DC EAF operation and increases energy efficiency, has been improved.

scholarly journals ENERGY EFFICIENT WATER-COOLED ELEMENTS FOR FOUNDRY CLASS ELECTRIC ARC STEELMAKING FURNACES

2021 ◽  
pp. 55-58
Author(s):  
S. Timoshenko ◽  
E. Nemtsev ◽  
M. Gubinski
Keyword(s):  
Energy Efficiency ◽  
Energy Efficient ◽  
Melting Process ◽  
Electric Arc Furnace ◽  
General Purpose ◽  
Electric Arc ◽  
Oxidation Potential ◽  
Low Energy ◽  
Specific Power ◽  
Arc Furnace

Possibility of a wide choice of original charge and variation of oxidation potential in melting process makes the electric arc furnace (EAF) a general-purpose unit in foundries. Energy-intensive classical technology with insufficient specific power of the transformer, irregular operation with forced downtime predetermine a low energy efficiency of foundry class furnaces [1,2]. Flat and shallow bath of the EAF enhances the problem.

Energy Conservation Potential in Stainless Steel Making by use of Molten Pig Iron and Liquid Ferro-Chrome

2013 ◽  
Vol 794 ◽  
pp. 124-131 ◽  
Author(s):  
Lokesh Kumar Singhal ◽  
Sudipta Patra
Keyword(s):  
Stainless Steel ◽  
Energy Conservation ◽  
Energy Efficient ◽  
Electric Arc ◽  
Steel Scrap ◽  
Pig Iron ◽  
Arc Furnace ◽  
High Carbon ◽  
Steel Making ◽  
Carbon Ferrochrome

Stainless steel is mostly manufactured by Electric Arc Furnace Argon Oxygen Decarburization route utilising 100% solid charge of steel scrap/DRI/stainless steel scrap and ferroalloys.The process consumes around 415/450 KWH of power per ton of stainless steel.In the state of Odisha, we are endowed with both iron and chromite ores,which offer opportunity for use of molten pig iron and liquid ferrochrome for energy efficient stainless steel making for a plant located there. This paper analyses potential for energy conservation in EAF for three different grades of stainless steel belonging to AISI 200,300,400 series. In this concept, melting is performed in two different furnaces,one EBT type and the other Spout type.In EBT furnace only high ferrous melt with liquid pig iron and DRI/Scrap are charged and dephosphorized. In the spout furnace high carbon ferrochrome which has a tendancy to solidify rapidly due to its high melting point of nearly 1575°C is diluted with scrap which brings down its melting point drastically to enable it to be kept molten.Silicon in the high carbon ferrochrome is gainfully utilised to raise the temperature of molten pool.The diluted ferrochrome is taken in ladle in appropriate portion to which dephosphorised decarburized molten steel is added from EBT furnace for charging into AOD. The material and energy balance have been carried out for the entire charge mix using classical approach of energy calculation. Both variants of DRI and scrap addition to hot metal have been considered for the EBT furnace. Calculations for EBT furnace have been validated using data from an existing carbon steel plant using similar practice of steel making. Calculated values for such energy efficient stainless steel making have been compared with data on existing stainless steel plant using solid charge. Energy usage can be reduced by more than 60% with this approach. Keywords: Electric arc furnace, Stainless steel melting, liquid ferrochrome, energy conservation.

Analytical Electron Microscopy Characterization of Electric Arc Furnace Dust

1981 ◽  
Vol 39 ◽  
pp. 134-135
Author(s):  
J. R. Porter ◽  
J. I. Goldstein ◽  
D. B. Williams
Keyword(s):  
Electron Microscopy ◽  
Analytical Electron Microscopy ◽  
Electric Arc Furnace ◽  
Electric Arc ◽  
Dust Particles ◽  
Particle Analysis ◽  
Arc Furnace ◽  
Analytical Electron ◽  
Residual Elements ◽  
Industry Practice

Alloy scrap metal is increasingly being used in electric arc furnace (EAF) steelmaking and the alloying elements are also found in the resulting dust. A comprehensive characterization program of EAF dust has been undertaken in collaboration with the steel industry and AISI. Samples have been collected from the furnaces of 28 steel companies representing the broad spectrum of industry practice. The program aims to develop an understanding of the mechanisms of formation so that procedures to recover residual elements or recycle the dust can be established. The multi-phase, multi-component dust particles are amenable to individual particle analysis using modern analytical electron microscopy (AEM) methods.Particles are ultrasonically dispersed and subsequently supported on carbon coated formvar films on berylium grids for microscopy. The specimens require careful treatment to prevent agglomeration during preparation which occurs as a result of the combined effects of the fine particle size and particle magnetism. A number of approaches to inhibit agglomeration are currently being evaluated including dispersal in easily sublimable organic solids and size fractioning by centrifugation.

Monitoring the environmental and energy impacts of electric arc furnace steelmaking

2016 ◽  
Vol 104 (1) ◽  
pp. 102 ◽  
Author(s):  
Valentina Colla ◽  
Filippo Cirilli ◽  
Bernd Kleimt ◽  
Inigo Unamuno ◽  
Silvia Tosato ◽  
...  
Keyword(s):  
Electric Arc Furnace ◽  
Electric Arc ◽  
Arc Furnace
Sign in / Sign up

Export Citation Format

Share Document