ABSTRACT During the charging process of the blast furnace, the charging sequence of the iron-bearing burden directly determines the mixing uniformity of sinter, pellet and lump ore in the throat. In this study, according to four different charging sequences commonly used in the production of a 5500 m3 blast furnace in China, the influence of the charging sequence of the iron-bearing burden on the uniformity

ABSTRACT The LD (Linz Donawitz) steelmaking process is the most used in the steel industry due to its high-volume capacity and low cost per ton of steel produced. However, the basic oxygen steelmaking process in LD converters is subjected to potential steel charge overflows, often called ‘slopping’. Besides yield losses, slopping events can damage the environment and expose employees to danger. More

ABSTRACT The influence of addition sequence of Mg, La and Ca on the characteristics of inclusions and the formation of acicular ferrite (AF) were investigated. Results show that inclusions mainly consisted of La–Ca–Mg–Al–Ti–O+MnS in the steel. There was no change to types of inclusions while the layered structure of inclusions was different under different alloy elements addition sequence. The number

ABSTRACT Three types of impellers are developed to improve reagent efficiency in the desulfurization process of hot metal by kanbara reactor stirring method. The movement and dispersion behavior of particles are investigated using the CFD technology. The flow structure, particle volume fraction distribution and mixing time are taken as the characteristics to describe the entrainment ability and mixing

ABSTRACT The kinetic models of hot-metal dephosphorization and rephosphorization have been widely used in the analysis of phosphorus mass transfer, but most of the existing models deviate greatly from the experimental results. Therefore, to reduce the deviation of traditional models in data fitting, according to the change in hot-metal phosphorus content during dephosphorization or slag phosphorus

ABSTRACT The reaction mechanism of CO/CO2 with low-carbon aluminium-killed molten steel in ladle furnace was investigated through thermodynamic analysis, simulation, and experiments. When a[O]×a[C] in molten steel is less than pCO/(pΘ × KΘCO), CO/CO2 gas is dissolved in the metal phase and decomposed into oxygen and carbon. When a[O] × a[C] is equal to or close to pCO/(pΘ × KΘCO), CO no longer reacts

ABSTRACT Impurity elements of Cu, Ni, Sn and Cr have been added to a model low-carbon strip steel to mimic the levels that could arise due to increased scrap recycling during steel production. The microstructure and tensile properties of the base composition and impurity added compositions after thermomechanical processing, consisting of hot rolling and simulated coil cooling, have been investigated

ABSTRACT In this paper, two kinds of cold-rolled 3.5Mn steels with different initial microstructures are designed. Combined with EBSD and dilatometer, the effect of Mn pre-partition on the austenite reversion and the mechanical properties in the subsequent intercritical annealing process are compared. The results show that the Mn pre-partition can significantly increase the austenite reversion rate

ABSTRACT FLDS (Fuel Layered Distribution Sintering) is a technology that can effectively reduce fuel consumption with evenly distributed heat pattern in the sintering bed compared to the conventional iron ore sintering. In this paper, a numerical model is established and used to predict the FLDS performance in terms of six different indicators such as FFS (Flame Front Speed), sintering time, maximum

ABSTRACT Good knowledge of the redistribution characteristic of solute elements is essential for the design and the production of new alloying systems. Part I of this series demonstrated the deviations of microsegregation predictions on an advanced high strength steel (AHSS) caused by equilibrium partition coefficients based on the analytical microsegregation model. In this study, the aim is to conduct

ABSTRACT A stave cooling system is a key element in the blast furnace which protects the outer shell from heat by providing uniform cooling. Real-time condition assessment of staves is essential to understand the wear mechanism of staves. Inspection rod/waveguide of known length which is made of copper was inserted through the steel shell till the inner end of the stave where the waveguide is susceptible

ABSTRACT Increasing the oxygen supply intensity of a converter is the main method of shortening the smelting time. However, the increase in oxygen supply intensity increases the splashing rate of the smelting process. Therefore, balancing these two phenomena is the content of many academic and metallurgical studies. However, the studies on the characteristics of O2 + CO2 mixed injection by a dual-parameter

ABSTRACT This article describes the simulation method for layering the components of the charge in the blast furnace, including the particle size distribution and gas flow distribution of bell-less top charging systems in blast furnaces. The Burden Distribution application, which simulates the charge in blast furnaces operated by the company Třinecké železárny (ironworks) to optimize the production

ABSTRACT To solve the problems of slag entrapment risk and frequent bond alarm in the field application of mould flux for high-speed thin slab continuous casting, the idea of ‘non-Newtonian fluid mould flux with shear-thinning property’ is introduced. It was found that with an increase in the Al2O3 content, the shear-thinning behaviour of the mould flux first increased and then decreased. The sample

ABSTRACT Blast furnace ironmaking usually requires maintaining a reasonable level of hot metal desulphurization; therefore, knowledge of the complex interplay between physical properties and desulphurization potential of slag is essential for the holistic approach to the operation. Several models for predicting sulphur partition between slag and hot metal based on sulphide capacity estimation have

ABSTRACT In the BOF steelmaking process, lime quality and quantity directly affect slag quality, affecting metallurgical results, liquid metal yield, productivity, and therefore the total cost and environmental impact of the steel production. In this paper, a value in use model based on mass balance and heat balance was developed and used to evaluate the impact of lime quality on the BOF process. The

ABSTRACT Microsegregation is an inherent phenomenon that occurs during the solidification of steel and can result in multiple casting defects. To explain and predict the microsegregation phenomenon, the analytical microsegregation model has been extensively used. However, equilibrium partition coefficients always play a critical role, and the deviations of microsegregation prediction caused by the

ABSTRACT In this work, a time-dependent thermodynamic AOD process model, TimeAOD3™, is proposed to be used as a prediction model at practice to reach the desired nitrogen level to lower the cost and carbon footprint. The model is developed from an existing model and integrated with Thermo-Calc®. The modelling results suggest a fairly good prediction when compared with production-scale heats. The relative

ABSTRACT The cross temperature measuring device is applied to monitor the top temperature and gas flow distribution in the blast furnace (BF) during the ironmaking process. However, the temperature of the BF roof is relatively high, which causes damage to the cross temperature measuring device. Therefore, this paper proposes an efficient estimation method. First of all, the data filtering method are

ABSTRACT It is very important to have a slag detection system (SDS) in steelmaking to detect slag and prevent its flow for improving the quality of steel produced. Slag raking is used for removing slag from liquid iron. Detection and control of slag may be carried out with the help of refractory dart or infrared imaging in the steel making zone such as in a Basic Oxygen Furnace (BOF). Each method has

ABSTRACT To measure the velocity of molten steel in continuous casting mould conveniently, a new method is proposed in this paper. The relationship model between thermoelectric force and velocity is established by using the Seebeck effect and the relationship between convective heat transfer and velocity. This model and method can be applied in more continuous casting production to realize the real-time

ABSTRACT To use vanadium–titanium magnetite (VTM) resources for sintering, a composite agglomeration process (CAP) is applied. This paper studies the effects of pelletizing parameters, including particle size, moisture content and bentonite content on VTM green pellets, composite agglomeration process and mineralogy. The experimental results show that the optimal pellets particle size, water and bentonite

ABSTRACT The kinetic investigation of the dephosphorization in the new double slag converter steelmaking process was carried out based on the coupled reactions model combining with a heat balance temperature model for the 220-ton industrial experiment. The calculated results of [%C], [%Si], [%P] in the hot metal, and the slag compositions are in good agreement with the experimental results. When the

ABSTRACT Blast furnaces (BF) ferrous burden consist of sinter (>50%) with rest being pellets and lump ore. Good sinter quality is necessary for efficient BF operation which depends on iron ore quality and its gangue. In gangue, alumina has a strong influence that adversely affects product quality and productivity. To address those effects this study presents a two-stage method. It involves the development

ABSTRACT To understand the thermodynamic characteristics of the melting process for high manganese twinning-induced plasticity steel, the activity coefficient of FeO in molten slag of MnO–CaO–SiO2–FeO–MgO slag system with up to 52 mass% MnO was measured at 1450°C by the experiments of the iron equilibrium between liquid silver and molten slag under the mixed gas atmosphere of CO, CO2 and Ar. The effects

ABSTRACT Various kinds of fuel such as high rank coal and coke breeze have been adopted over the years. However, their low combustion efficiency levels have given rise to the production of alternative fuels such as charcoal, biomass, semi-coke breeze, solid waste and gas, but the most extensively applied in recent times is semi-coke due to its high combustion efficiency and low pollutant emission level

ABSTRACT According to the mould electromagnetic stirring of vertical round billet continuous casting, a three-dimensional mathematical model of electromagnetic field was established to study the distribution of magnetic field in the mould. On the centre cross section of agitator, the distribution of magnetic flux density is small in the centre and large in the edge, in the centre longitudinal section

ABSTRACT This work investigates the melting behaviour of iron ore with calcium-based fluxes, including lime, limestone and basic oxygen furnace (BOF) steelmaking slag. With an aim to explore the potential kinetic benefits that can be obtained through the formation of a liquid medium on the overall productivity of HIsarna. A HT-CLSM was used to rapidly heat and observation the interface between a given

ABSTRACT The extensively published models of the ESR process assume a singular value of the slag thermal conductivity and employ that value in a format which assumes heat conduction entirely by a phonon mechanism. In this work we investigate the possibility that the mechanism is a phonon/photon mechanism in a slag which is diathermanous. The conclusion is that such a model assumption better represents

ABSTRACT Emission amount of blast furnace gas (BFG) is huge per year and it cannot be directly combusted due to its low heat value. Separating and Enriching CO from blast furnace gas provides an effective way for its utilization. This paper proposes an improved adsorption isotherm model of CO on CuCl/Y adsorbent. A CO/CO2/N2 multi-component adsorption equilibrium model and a set of mathematical models

ABSTRACT A three-dimensional magnetic-flow-heat coupling model was established to study the metallurgical behaviour under different flow control devices in the channel-typed induction heating (IH) tundish. As compared to the prototype tundish, the results suggested that the maximum temperature difference between each strand and the tundish dead zone ratio are decreased by 0.75 K and 5.24% while with

ABSTRACT The data obtained on 220-T ultra-high power electric arc furnace (EAF) were analysed in order to study the impact of DRI quality on the steelmaking process parameters and consumption of lime, coke, oxygen, natural gas, electrical energy and electrodes. In addition, the effects of charging methods and proportions of DRI in an EAF were studied. It was found that by increasing the proportion

(2021). Steel World – Editorial Review. Ironmaking & Steelmaking: Vol. 48, STEED WORLD ISSUE, pp. 483-484.

ABSTRACT MnS inclusions in steels usually have many kinds of morphology. It is difficult to accurately obtain the characteristics of inclusions by two-dimensional observation due to the complex morphology of sulphides in steel, especially the type II MnS inclusions. In this study, the three-dimensional morphology of sulphide in high sulphur steel was investigated by using non-aqueous solution electrolytic

ABSTRACT A comparative study of precipitates, microstructure, texture and magnetic properties between conventional and Nb-bearing grain oriented silicon steel was carried out. The results show that fine and dispersed Nb-bearing particles are formed in Nb-bearing steel and show stronger pinning force during the whole heat treatment process, which makes a significant effect on the microstructure and

ABSTRACT The composition of Bayan Obo iron ore concentrate is complex. If a large proportion is used to prepare pellets, abnormal swelling will occur during blast furnace smelting. This paper studies the swelling behavior of pellets prepared from Bayan Obo iron ore concentrate in stages during the reduction process; XRD and SEM-EDS analysis and calculates the crystal parameters of the reduction products

ABSTRACT Intelligent iron/steel manufacturing has been drawing increasing attention in recent years. Slagging is of importance for clean steel production in the ladle furnace (LF) refining process. In this study, a calculation model of slag-making materials was established based on the actual LF refining conditions, the metallurgical mechanism model and the production data model of the sulphur distribution

ABSTRACT When producing cold-rolled steel sheets, the penultimate annealing process is followed by a final skin-pass rolling (or temper rolling) whose purpose is to eliminate any discontinuous yielding which creates stretcher–strain markings when the steel sheets are formed. To find out the critical reduction ratio eliminating the discontinuous yield phenomenon, the samples were annealed at 820°C for

ABSTRACT In the present work, a new ladle dephosphorization process has been developed using the dispersed in situ phases induced by an explosive reaction of the composite balls with slag forming materials. A composite ball with this function has been designed and prepared using a laboratory model batch type balling disc (at 12 rev min−1) and then has been fed during the convert tapping process. The

ABSTRACT The correct thickness of the shell solidifying within the primary cooling zone of the continuous casting machine is among the most important parameters assuring the safe operation of the casting process. The main problem is related to the fact that the actual measurement of the thickness of steel solidifying in the mould is impossible. Available continuous casting process monitoring systems

ABSTRACT The characteristics of inclusions and the formation of acicular ferrite (AF) in Ti–Mg-Ca killed EH36 steel were researched. Typical inclusions in the Ca-free samples were MgO·Al2O3 + MnS and pure MgO·Al2O3. With the addition of Ca, MgO·Al2O3 was modified into Mg–Ca–Al–O , which promoted MnS precipitating on those inclusions. Mg–Ca–Al–O+MnS/MnS–CaS was the nucleus of AF. While pure MgO·Al2O3

ABSTRACT The continuous cooling transformation (CCT) diagram of 30CrMo steel simulated by compact strip production process was constructed. And the effect of austenite deformation on the CCT behaviour was investigated. The results showed that the microstructure gradually transformed from proeutectoid ferrite and pearlite to bainite and martensite with the increase of cooling rate, accompanying a refined

ABSTRACT Coke–slag–metal samples located near the deadman edge and below the taphole of blast furnace were obtained by core drilling after cooling. The chemical composition, microstructure, phase composition and distribution of samples were studied in detail. In addition, the graphitisation degree of coke in hearth was also investigated. The results showed that coke larger than 60 mm still existed

ABSTRACT The kinetics of the reduction of magnetite concentrate particles by H2+CO mixtures have been investigated in drop-tube reactors (DTRs) to obtain rate expressions for the design of novel flash ironmaking reactors. The experimental temperature varied from 1423 K (1150°C) to 1873 K (1600°C). The H2/CO ratio was varied from 0.5 to 2, which is the typical composition range of the product gas from

ABSTRACT The cooling intensity of laminar cooling determines the microstructure of metal materials, thus affecting the performance of products, while the heat transfer coefficient directly affects the cooling intensity. A method to obtain the heat transfer coefficient of laminar cooling is proposed in this work. The distribution form of the heat transfer coefficient is obtained as a piecewise function

ABSTRACT The tuyère injection is one of the key tools to exhaust the blast furnace potential and to minimize its CO2 emissions. The review argues theoretical basis and operation strategies for ensuring the high efficiency of injection of auxiliary reducing agents (ARA). First, it provides the theoretical analysis of requirements that ensure minimum coke and carbon rates, and minimum CO2 emissions.

ABSTRACT In this study, both blanking and fine blanking processes were performed using 1mm thick DP600 and DP800 sheet materials. The cutting surfaces of the materials were examined using scanning electron microscopy (SEM). The SEM examinations showed that the extent of the fracture zone in the blanking method was much greater than in the fine blanking method, whereas the extent of the shear zone in

ABSTRACT In hot metal desulphurisation (HMD) the slag will hold the removed sulphur. However, the iron that is lost when the slag is skimmed off, accounts for the highest costs of the HMD process. These iron losses are lower when the slag has a lower viscosity, which can be achieved by changing the slag composition. A lower slag basicity decreases the viscosity of the slag, but also lowers its sulphur

ABSTRACT The optimal hot metal desulphurisation (HMD) slag is defined as a slag with a sufficient sulphur removal capacity and a low apparent viscosity (ηslag) which leads to low iron losses. In part I of this study, the fundamentals behind the optimal slag were discussed. In this part these fundamentals are explored by a Monte Carlo simulation, based on FactSage calculations, plant data analysis and

ABSTRACT The flux pellets as the burden materials of blast furnace have been widely investigated and used. However, its research and practical applications keep slowly developing in China due to the historical status of the sinter and the limitation of raw material condition. The sinter output is constrained by the environmental department due to its great emission of air pollutants. Therefore, enhancing

ABSTRACT The composition, morphology, number, area, size and average distance of inclusions in Fe–23Mn–xAl–0.7C steels were evaluated through an inclusion automatic analysis system (INCA Feature). According to their composition and morphology, six types of inclusions are classified in the present steels: MnS(Se), AlN, Al2O3, AlN–MnS(Se), Al2O3–MnS(Se), and other inclusions (i.e. Al2O3–AlN and MgO–Al2O3)

ABSTRACT The global warming promotes the steel industry to replace part of coke by injecting hydrogen-rich fuel into the blast furnace to reduce CO2 emissions and energy consumption. In this paper, the injected hydrogen-rich fuels and effects of hydrogen-rich smelting on burden reduction and property evolution were introduced, and the hot events related to hydrogen metallurgy were summarized. Increasing

ABSTRACT With the development of a large-scale blast furnace, hearth activity has an important impact on the longevity and efficiency. Based on the analysis of practical example of ShaSteel No. 3 blast furnace, the new hearth activity model was proposed and verified, namely, the slag-iron flow resistance coefficient. Besides, in the model, the prediction of the coke particle size in the hearth was

ABSTRACT There is a growing drive within the steel industry to increase scrap usage in the Blast Furnace (BF)-Basic Oxygen Furnace (BOF) integrated route and extend the scrap-based Electric Arc Furnace (EAF) route for steel production due to the resultant reduced energy costs and CO2 emissions and the abundant steel scrap supply in the UK. In general, steel scrap may contain high levels of undesirable

ABSTRACT In the present study, some steel and slag samples were taken in industry to investigate the effect of slag adjustment on the inclusions in tyre cord steel. The disadvantage of slag adjustment process was discussed in contrast to the process with low basicity slag. The results show that the overall evolution routes of inclusions are the same in both processes with and without slag adjustment

Submerged CO2–O2 injection is a new method for electric arc furnace (EAF) steelmaking. And it’s necessary to optimize the arrangement of submerged nozzles and oven wall oxygen lances used in an EAF. In this study, the characteristics of metallurgical reaction in EAF metal bath during submerged injection and oven wall oxygen supply were analysed. The submerged nozzles’ agitation action was focused on

ABSTRACT The morphology of eutectic carbide was studied by application of a transverse static magnetic field (TSMF) during the directional solidification of M2 high-speed steel. The results show that the morphology of eutectic carbide changed from lamella to fibre as the magnetic flux density (MFD) increased from 0 to 1 T. The transformation from lamella to fibre has been enhanced by the increasing

ABSTRACT It is of great significance to improve the yield of ferroalloy for steelmaking to reduce cost and save energy. In this paper a kind of loss mechanism of micro-carbon ferromanganese which has micro content of carbon during RH refining of interstitial free steel was investigated. The flow field of argon gas in the RH degassing vessel was investigated through numerical simulation. Through force

ABSTRACT Top gas recycling technology is an effective means to reduce fuel consumption and CO2 emission in the ironmaking field. In this work, a static mathematical model of COREX process combined with top gas recycling technology is developed based on material and energy balance. The influence of three types of top gas recycling, such as the recycle gas without CO2 removal (RG-1), the recycle gas

ABSTRACT In the present study, the influence of industrial sinter machine speed on the temperature distribution of the bed is evaluated using a one-dimensional transient mathematical model. The model is developed considering the law of conservation of mass, momentum, and energy of solid and gas phases. The prediction of bed temperature from the model is compared with the measured lab scale pot test