Influence of Onesteel’s Furnace Operating Parameters on Energy Efficiency
during EAF Steelmaking
Energy Efficiency during EAF Steelmaking is dictated by a wide range of operating
parameters which influence slag foaming. The focus of this study was to investigate
influence of operating parameters on electrical power consumption and develop an
understanding regarding the influence of these parameters during operation. This study
is being conducted in parallel with fundamental investigation of influence of parameters
on slag foaming in a laboratory-scale furnace. Conducting parallel studies based on
plant data and laboratory measurements, will shed fundamental insights on the influence
of operating parameters which could then be applied to the EAF operation.
Slag foaming practice has been widely adopted in EAF steelmaking. Foamed slag
shields the arc struck between the electrodes and the bath, thereby reducing the
radiative heat losses from the bath and improving the efficiency of electrical power input
to the bath. This allows higher power input to the furnace while minimizing the risk of
damage to the furnace roof, sidewall refractories and water cooled panels. Therefore,
one of the most significant benefits of slag foaming is increasing EAF energy efficiency.
In this paper, influence of parameters including coke injection and oxygen injection on
energy efficiency is investigated on the basis of operating data from Onesteel’s minimill
Coke injection was seen to be more effective in increasing energy efficiency when
compared to oxygen injection. This could be explained on the basis that coke injected
plays an important role in reducing iron oxide in the slag and thereby generating small
and more stable bubbles of CO, which leads to a more stable foam. Carbonaceous
material and its associated properties dictate the interactions of slag and carbon such as
reduction of iron oxide and interfacial phenomena. The material properties that govern
such interactions are carbon structure and ash content/composition.
Experience of Using Natural Mineral Reducer in Ironmaking
An experience of using newly discovered natural reducer called “shoungit”, has been
amassed in Russia. Shoungit is a unique mineral rock, which contains 90% of finely
dispersed mixture of C and SiO2 in Ratio, close to a stoichiometric value, needed for the
reaction to generate SiC. It features an expansive specific contact surface (more than 2
M2/GR). At reheating, the interaction between C and SiO2 in shoungit would start going
at the temperature that is by 150-200 degrees C lower and with heat consumption also
lower than it would have been the case in the mixture of charcoal and quartz sand.
Lump-size shoungit is used in making foundry and basic iron and ferroalloys in blast
furnaces. Coke by shoungit substitute ratio in making basic iron is 0.5 – 0.7 kg/kg, in
foundry ironmaking it is 0.9 – 1.1 kg/kg, in making ferromanganese – 1.0 – 1.2 kg/kg.
Crushed shoungit can be also used in preparing runners compounds.
Influence of MgO and Al2O3 on CaO-SiO2-Al2O3-MgO-FeO Slag
Although the physical properties of BF slag such as viscosity have been reported, few
viscosity data of the CaO-SiO2-Al2O3-MgO(-FeO) slags in the bosh level containing FeO
have been reported. In this paper, the viscosities of CaO-SiO2-Al2O3-MgO(-FeO) slags
will be measured by employing the rotating cylindrical method and the effect of each
component on viscosity of slag will be discussed.
Thermodynamic Behavior of Chlorine in Blast Furnace Slag
The injection of waste plastic and low quality coal containing chlorine into a blast furnace
can cause the problem of dioxine and HCl generation as well as the erosion of
refractoies. However, few data are available for the thermodynamic properties of
chlorine in the blast furnace slags. Thus, in this paper, the solubility of chlorine in the
CaO-SiO2-Al2O3-MgO slag will be measured and the thermodynamic behavior of chlorine
will be discussed.
Comparison Between Gas and Oil Injection into the Blast Furnace: A Detailed
The combustion behavior of coke oven gas and fuel oil in the raceway of a blast furnace
was analyzed. The interaction of gas flow, drop motion, evaporation, turbulent mixing
and oxidation were considered. With a commercial CFD-code it was possible to solve
this problem. The results demonstrate the significantly different combustion behavior of
gas and oil.
Improved Materials and Powertrain Architecture for 21st Century Trucks)
This paper will present the CAE driven process used in IMPACT (Improved Materials
and Powertrain Architecture for 21st Century Trucks). IMPACT project was a project
jointly funded by Ford Motor Company, U.S. Army, and American Iron & Steel Institute.
This project delivered a Ford F-series design at 25% weight reduction from the existing
model. This paper will discuss the CAE analyses (including NVH, safety, durability, and
formability) used to optimize the architecture and implement new advanced high strength
steel materials to achieve the aggressive weight reduction targets set for different
systems of the vehicle including body, frame, suspension, and powertrain.
Mathematical Modeling of Fine Iron Ore Reduction under Fluidized Bed Conditions
Based on reduction tests in a batch reactor a kinetic rate expression for iron ore
reduction was developed. The reduction can be divided into three phases of different
kinetics depending on the reduction degree. This rate expression was incorporated in a
model. With this model the reduction degree of the iron ore and the gas concentrations
in continuously operating fluidized bed reactors in series can be calculated.
Effect of Granulating Method of Waste Plastics Injected into Blast Furnace on
Environment Issues and the Use of Resources
In order to select optimal granulating method of waste plastics injected into blast
furnace, the effect of three granulating methods on environment issues and the use of
resources was investigated. The result showed that the method by light heating
extrusion is the best, it didn’t cause second pollution and the carbon and hydrogen in
waste plastic almost fully was recycled.
The Study of the Basic Operation System of the Shougang No. 1-3 BFS
The basic operation system of the No 1-3 BFs has been analysed. The regulating
direction of the charge system has been advanced by the way of PCI rate hoist, the
relation of LO/LC and the value of throat gas CO2% has been discussed. The regulating
direction of the blasting system at the different seasons has been discussed.
The Affect of the Change of Coke Quality to the Smelting Institution of the
The affect of the change of coke quality to the brim and center temperature of the cross
temperature at the No. 2 BF has been analysed. The relief measure of the charging
system has been advanced in the condition of lower coke quality. By the means of
analyzing the example, the comeback measure that the BF is out of gear has been put
forward, the methods of stabilizing BF production has been advanced at present.
The Melting Rate of Single HBI Briquettes in Steel Baths
An experimental and modelling program has been conducted by BHP Billiton to study
the rate and mechanism of melting of HBI during steelmaking. Single briquettes melt
relatively quickly due to vigorous stirring from CO evolution. The melting rate is
determined by the bath carbon level, with briquette carbon only important in a low
carbon bath (< 0.1 wt%).
Mechanism of Iron Oxide Reduction by Simulated Volatiles
In processes using coal and ore, volatiles can contribute to reduction. Therefore, the rate
of iron ore reduction by hydrogen at lower temperatures was studied. The results
indicate a mixed control mechanism of nucleation, mass transfer and chemical kinetics.
The Relining of Kokura No.2 Blast Furnace by Utilizing Some Parts of Shut-
downed Blast Furnaces
Kokura new No.2 blast furnace was relined and blown in April 10, 2002, and is now
operated under stable condition. (Productivity 1.86t/D•Em3, PC rate 130kg/THM,
Reducing agent rate 490kg/THM). The feature of this relining is to utilize some shut-
downed blast furnaces'mantels and tapping machines for new blast furnace.
Information of Tuyere Drilling Exercises About Changes in Coke Properties During
its Passage Trough the Blast Furnace
At Rautaruukki, Finland, the blast furnace tuyere drilling program has commenced using
the new mobile core drilling rig with a sample tube of 205 mm inside diameter. At this
stage of the drilling exercises detailed physical and chemical analyses of the +20 mm,
10-20mm and 5-10 mm drill core cokes were carried out to evaluate changes in the coke
during its passage through the furnace, in relation to BF operation and feed coke used.
During the tuyere drilling period in question the most significant difference in BF
parameters compared was between the bottom temperatures which at BF1 was clearly
lower compared to BF2. The same feed coke was in use at both the furnaces but there
were two weeks between the monthly stoppages (drilling day).
A difference was found in coke behaviour between the furnaces but the individual drill
cores at each furnace followed rather similar trends. Of course there is scatter in harmful
BF working indicators between the profiles from the same BF during the five months
examined. We do not know which reason is likely for this: coke quality (CSR = 62.8 -
66.7 %) or scatter in furnace operational state.
The classification of drill core sections ( bosh, raceway, bird’s nest and deadman) is
based on such characteristics as coke size, shape and colour, extent of
graphitisation/wetting by iron and proportion/size of iron and slag present. With each
case of increased deadman blockage from –0.5 mm fines a decrease in iron droplet size
(connected to bird’s nest agglomerate) and appearance of slag were evident.
There were obvious drill coke factors, see below, which reflected sharp temperature
decrease and the forming of an impermeable central region in the blast furnace.
Both attack by microsized iron (up to 15 % in +20 mm coke) in the flame zone of
raceway and internal micro-corrosion (up to 80 % porosity) through coke abrasion
loss, generate coke and iron fines.
Enrichment of slag in end part of raceway (S up to 1 % in 5-10 mm drill core).
Accumulation of volatile matter (up to 0.95 % in +20 mm coke) with alkalis (up to 6.5
%) in deadman.
Breakdown of coke CSR, as low as 3 %, in deadman but maintained mechanical
cold abrasion resistance, however, near to that of the feed coke.
Reduction in iron droplet size and disappearance of pitting corrosion in coke.
Tobata No.4 BF Operation at High Productivity and High PC Rate (1998-2003)
Tobata No.4BF (I.V. 4250m3) has continued high productivity (2.3-2.
4t/d/m3)and high PCR (150-160kg/t) operation for five years since the blow-in in Feb
1998. This has been enabled by optimization of blast burden distribution through test
operation and activation of deadman cokes under control of hearth condition.
Pig Iron Granulation at Iscor Saldanha Steel
A Granshot™ iron granulation plant was commissioned at Iscor Saldanha Steel (South
Africa) in November 2002. The plant design is fulfilling its task and thousands of tons of
hot metal passes through the granulator every month for further use in the steel plant.
This paper discusses the operational experiences achieved and the value-in-use of a
granulator in integrated steelmaking.
Development of a New Reduction and Smelting Process in a Rotary Heath Furnace
Hi-QIP is a new coal based process to produce high quality iron. This is characterized by
separating iron pebbles from melting slag in a rotary hearth. The carbonaceous material
layer on the hearth controls the iron shape and protects the hearth refractory from
molten slag. After the successful bench tests, the project of 15t/d pilot plant has been
carried out with the fund from the Key Technology Research Promotion Program of the
New Energy and Industrial Technology Organization.
Development of Curtain Flame Sinter Ignition
To improve the ignition of top layer of sinter mix and to reduce the specific gas
consumption, Research and Development Centre for Iron and Steel (RDCIS) of Steel
Authority of India Limited (SAIL) has developed curtain type flame based ignition system.
The concept involves mounting the small capacity burners on the roof across the sinter
bed in single row. The new ignition system was installed and commissioned in
machine#1 of Sinter Plant at Bokaro Steel Plant of Steel Authority of India Limited. The
furnace volume has come down by 90%. It has resulted in more than 50% savings in
specific gas consumption.
Laboratory Study of Flooding Phenomenon in the Lower Blast Furnace with
High Pulverized Coal Rates Injection
The flooding phenomenon in the lower blast furnace was studied in laboratory scale by
taking into account high coal rates injection. No typical fluidization phenomenon could be
observed under the experimental conditions. Regressive expressions have been
established for the occurrence of choking and flooding phenomena based on the test
Thermal and Dynamic Study of Rapid Cooling in Continuous Galvanizing Lines
The production of new steel grades requires the improvement of rapid cooling
technology. The increase of cooling capabilities can however be limited by the strip
vibrations. Experimental and numerical study of the performances of such a gas cooling
system is presented. The dynamic behavior of the strip is also studied at both industrial
and laboratory levels.
The Experiment of IR Camera at the Tuyeres in 1200m3 Blast Furnace of
Panzhihua Iron and Steel Co.
The experiment of IR Camera at the tuyeres of 1200m3 BF was carried out at Panzhihua
Iron and Steel Co. Through the IR Camera at the tuyeres, the lightness, the activity of
coke, the amount of coal injection and its changing can be observed on-line and
continuously to guide the BF operation.
The Application of Cigar IR Camera System at 2536m3 BF of Capital Iron and Steel
The Cigar IR Camera system was installed at NO.1 BF at Capital Iron and Steel Co. The
gas distribution image inside the BF can be observed at real time, the temperature
distribution can be obtained by computer disposing. After applying this system, the BF
worked steadily and smoothly and achieved high productivity and low consumption, and
avoided the equipment accident.
The Blow-in Practice of 1750m3 Blast Furnace by Adopting the Technology of
Charge Measurement and Cigar IR Camera
The new 1750m3 BF at Jinan Iron and Steel Co. blew in on the August 31, 2003. The
charge measurement was carried out. After ignition, the Cigar IR Camera system was
used to observe the situation of gas distribution, and then the charging mode can be
regulated to make the BF blow in steadily and rapidly.
Dephosphorization of Molten Steel by BaO- CaO-CaF2 Slags
The molten steel was dephosphorized by the high basic BaO-based flux (BaO-CaO-
CaF2) in order to achieve ultra low phosphorus level. The dephosphorization ability of
this flux to the low phosphorus steel was investigated. The thermodynamics properties of
BaO-CaO-CaF2 flux were analyzed. It was measured that at 1620℃ the
phosphate capacity of this flux varied from 1018.03 to 1019.11 , and the activity
coefficient of P2O5 ranged form 10-19.47 to 10-17.58. Effects of the BaO content, the
initial phosphorus content and the oxidizability of the molten steel on the
dephosphorization of the molten steel were discussed. The decreasing of the
phosphorus pick-up by this BaO-based flux was studied.
Statistical Modeling of Austenite Formation in Steel
The present investigation introduces the statistical processes models for the empirical
modeling of the formation of austenite during the continues heating of steels. At the
previous works has examined the application of neural networks and Guassian process
model to this problem, but the Guassian and Gamma Inverse processes. Models are a
more general probabilistic models and are somewhat more amenable to interpretation. It
is demonstrated that the models lead to an improvement in the significance of the trends
of the Ac1 and Ac 3 temperatures as a function of the chemical composition and heating
rate. In some cases, these predicted trends are more plausible than those obtained with
neural network and Guassian process analysis’s. Additionally it is shown that many of
the trace alloying elements present in steels are irrelevant in determining the austenite
Effect of Calcium Treatment on Microinclusions in Non-oriented Silicon Steel
The iron loss P1.5/50 of non-oriented silicon steel decreases 0.204W/Kg on an average
after calcium treatment. The amount, size distribution and type of microinclusions are
studied by metalloscope, image analytical apparatus, scan electronic microscope and
transmission electronic microscope. Two methods are used to describe the amount of
microinclusions. the effect of calcium treatment on microinclusions and the effect of
microinclusions on iron loss is discussed in this paper.
Improved Magnetic Flow Control Device using EMBR
To improve the surface quality of ultra low carbon steel, mold flow control is necessary.
POSCO has various type of electromagnetic flow control devices except EMS and
understand the merits of each devices. And finally, to maximize the efficiency of EMBR
device, magnetic profile designed by numerical analysis was designed and adapted in
slab caster. Surface defects was drastically decreased when newly designed magnetic
field was applied.
"NO LANCE" Ladle Stir Plug Technology Improves Productivity and Stir Reliability
Gas stirring systems are a well established and critical link for Ladle Metallurgy in
steelmaking and foundry operations providing homogenization of temperature and
chemistry, removal of inclusions, efficient addition of alloys and expedited metallurgical
processing, such as desulphurization. This paper identifies a new purge plug system
that does not routinely require oxygen washing of the purge plug hot face during ladle
turn around. The new " NO LANCE" plug is designed to be self-starting. Intensified flow
patterns are achieved using a combination of size controlled capillaries interconnected in
a lattice web along with very fine slits that resist metal infiltration. The intensified self
starting jets achieve improved stir reliability and productivity.
A review of the evolution of gas stirring technology culminating in the design of the " NO
LANCE" plug includes current recommendations for optimizing ladle stirring reliability.
Typical wear mechanisms are examined with findings showing a principal limiting factor
on stir plug life is erosion of the refractory due to attack by oxygen during plug washing
and exfoliation of the hot face due to alteration by slag penetration. A new refractory
composition of lower porosity, higher density, higher hot strength and higher corrosion
resistance further reduces the wear rate per heat. Results achieved with the "NO
LANCE" plug at recent steel plant applications show that intensified jet action improved
stir plug reliability, improved ladle turnaround time resulting in improved shop
productivity; increased heat retention in the ladle contributes to reduced loss of liquid
steel temperature and reduced oxygen washing results in less plug and block wear for
longer service life and cost savings.
Rubber Tired Transport and Tracking of Semi-Finished Products by DGPS
DGPS and telemetry equipment has been attached to rubber tired slab carriers at
Stelco, Hilton Works, to position and locate steel slabs. Slab transporters are tracked in
real time allowing accurate monitoring of slab positions by customized tracking software.
Steel mills benefit from this system through cost savings by: 1) allowing just-in-time
rolling schedules, 2) reduced slab inventory, 3) enabling the rolling mill to determine a
least cost rolling schedule, and 4) elimination of misplaced or lost slabs.
STEEL STRIPS-The Long and Winding Road
Sheet steel products are ubiquitous, enjoying a dominant share of the appliance and
transportation sectors. Apart from unmatched strength/weight ratios, another reason for
the dominance of steel sheet over plastic and aluminum sheet has been the fiercely
competitive nature of the steel industry itself. There, high steel yields and high
productivity are pre-requisites to survival within a global marketplace. Over the years,
the methods of steel sheet production have undergone major transformations, as the
industry moved away from rolling ingots, to rolling slabs, then thin slabs, and now direct
casting to thin strips. To match the production capabilities of a conventional slab caster,
producing slab at 1.4 m/min 200mm thick, a net shape caster producing 1mm thick strip
of an equivalent width, must run 200 times faster, or 4.7 m/sec. To date, casting
velocities of about 2m/sec are being reached! The story of steel sheet production over
the last century provides a fascinating example of the long and winding road
researchers, inventors, and practioners continue to follow. A "holy grail" for net shape
casting is now to reach bulk amorphous metal sheet as a new route towards ultra-fine