Electric arc furnace Research Papers (original) (raw)

2025, 2008 IEEE Energy 2030 Conference

The productivity ofAC electric arc smelters widely used The arc voltage is increased by operating with longer arcs; in the nonferrous metals industry is related to the arc voltage. however this also increases arc power fluctuations which Attempts to improve productivity with longer arcs and higher arc cannot be compensated for by the slow mechanical voltages give rise to power fluctuations which cause voltage flicker adjustments in use. In extremis such fluctuations cause arc and frequent arc reignition failures. The furnace power is reignition failures, followed by periods of asymmetric commonly regulated by moving the electrode rods to adjust the arc furnace operation associated with reduced power and length. A 100 MW AC arc furnace power supply equipped with . . semiconductor switched regulation windings which greatly unbaatrsse on neighbong electict c onsumers and enhance furnace power control bandwidth is presented, along with generators. The power fluctuatons also put strain on the suitable winding arrangements, semiconductor topologies, hydraulic electrode regulation used for power regulation in harmonic filters and commutation methods. This system was present plants and cause voltage flicker. simulated together with a Cassie-Mayr dynamic arc model. The By improving the furnace power regulation, the flicker can simulation model as well as the four-step commutation sequence be reduced and the arc voltage increased, reducing operating has been experimentally verified by building and testing a single costs by lowering wear and grid disturbances. phase 230 V, 2 kW PWM modulated tap-changer. The simulations and experiments demonstrate that power-electronic transformer II. FURNACE POWER REGULATION tap-changers with the ratings necessary for AC arc furnace power supplies are within reach of current semiconductor technology. They are significantly more effective at AC arc furnace power Power regulation aims to maintain a certain power in the regulation in terms of device rated power than controlled series presence of disturbances. This situation can be represented by

2025, Jurnal Teknologi

Several thousands of tons of electric arc furnace slag (EAF) slag generated in Nigeria are yet to be utilised for construction; perhaps as a result of inadequate technical details for its use. The present study has evaluated the effects of varying water-cement ratio on workability and strength of locally generated steel slag aggregate (SSA) concrete. Tested samples include 150 mm concrete cubes and cylinder samples with 150 mm diameter and 300 mm height respectively. SSA was substituted in increments of 20% by weight of granite until 100% mix, while w/c was varied at 0.5, 0.55 and 0.6. Workability of fresh concrete was evaluated through slump test. Hardened concrete cubes and cylinders were subjected to compression and split tensile tests respectively, after 7, 14 and 28 days curing periods. Slump values obtained were in the range of 50 – 90 mm for all the mixes, which represented a S2 slump. Compressive strength and tensile strength increased with age and increasing slag substituti...

2025, Sensors (Basel, Switzerland)

This research proposes a new index to evaluate the stability of the melting process, in three-phase electric arc furnaces (EAFs), based on the acoustic signals generated during the different stages of the casting. The proposed stability index is obtained by characterizing the time and frequency domain of the acoustic signals. During EAF monitoring, acoustic signals were acquired using a microphone coupled to an NI USB-9234 acquisition system. To validate the results, the voltage and current signals were measured with the aid of a Circutor AR6 power analyzer for three-phase electrical networks. The results showed that the acoustic signal energy in the frequency range of 1 to 12 kHz can be used as an indicator of the process stability in the EAF. Finally, the validity of the proposed stability index is evaluated from the process characterization using the harmonic distortion analysis methods and the dynamic U-I characteristics of the arc voltage and current signals. The results obtain...

2025, Naukovyi Visnyk Natsionalnoho Hirnychoho Universytetu

Purpose. To achieve a decrease in energy and resource costs in the multi-stage production of rolled products within a given plan through the development of appropriate mathware. Methodology. The multi-stage problem mathware for producing rolling steel products is developed on the basis of system approach applying fundamental principles of the optimization and operation research theory. Realization of the developed mathematical model allows discovering such a strategy of using steel during the whole manufacturing process, which minimizes not only the steel waste at the moment of its casting in a mold, but also the offcuts in the process of cutting the obtained ingots into the billets. Findings. A mathematical task model is built to minimize the amount of steel for producing a certain order of size of one cast volume only. The developed model specifies the possibility to pre-evaluate the billet optimal size, based on the necessary cutting along the final product length, appropriate fo...

2025, Aerosol and Air Quality Research

Iron and steel industry is crucial for economic development. However, large exhaust volume and complex feeding of the steel-making process results in enormous emissions of air pollutants such as particulate matter (PM), sulfur oxides (SO x ), nitrogen oxides (NO x ), polycyclic aromatic hydrocarbon (PAHs) and carbon monoxide (CO). This study sampled and analyzed the concentrations of PM, PAHs, SO x , NO x and CO at the inlet and outlet of the air pollution control devices (APCDs) adopted in sintering process (SP) and electric arc furnaces (EAF), respectively, to evaluate the performance of APCDs and emission characteristics of these air pollutants. The results show that filterable PM (FPM) concentrations measured at stacks of SP and EAF are 8.2 ± 1.3 and 13.6 ± 2.2 mg Nm -3 , respectively. The FPM 2.5 concentrations emitted from SP and EAF are 1.8 ± 0.5 and 3.2 ± 1.1 mg Nm -3 , respectively, while the condensable PM (CPM) concentrations emitted from SP and EAF are measured as 37.7 ± 1.3 and 3.4 ± 0.8 mg Nm -3 , respectively. Moreover, the flue gas desulfurization (FGD) and selective catalytic reduction (SCR) equipped in SP removed 82% and 58% of SO x and NO x , respectively, whereas SO x and NO x emitted from EAF are relatively low (< 1 ppm). The overall PAH removal efficiencies achieved with the APCDs adopted by SP and EAF are 72% and 26%, respectively. For total toxicity equivalency quantity (TEQ) PAH concentrations, similar results for SP (5.45 µg-BaP eq Nm -3 ) and EAF (4.74 µg-BaP eq Nm -3 ) are obtained. Moreover, the diagnosis ratios of FL/CHR, FL/(BaA + CHR), Pyr/5-MC and Pyr/(BaA + CHR) are suggested as the indicators for EAF. The emission factors calculated indicate that operating conditions of the APCDs in the SP investigated are well controlled. The concentrations of air pollutants emitted from SP investigated are lower than other studies. On the other hand, the concentrations of FPM and PM 2.5 emitted from EAF are higher than other studies. However, NO x , SO x and PAHs are well controlled. Moreover, the CO emission factors calculated from these two steel-making processes are higher than most reports. Overall, the operation of APCDs should be improved to reduce air pollutants emitted from these two steel-making processes.

2025, Aerosol and Air Quality Research

2025, IEEE Access

Combining classical technologies with modern intelligent algorithms, this paper introduces a new approach for the optimisation and modelling of the EAF-based steel-making process based on a multi-objective optimisation using evolutionary computing and machine learning. Using a large amount of real-world historical data containing 6423 consecutive EAF heats collected from a melt shop in an established steel plant this work not only creates machine learning models for both EAF and ladle furnaces but also simultaneously minimises the total scrap cost and EAF energy consumption per ton of scrap. In the modelling process, several algorithms are tested, tuned, evaluated and compared before selecting Gradient Boosting as the best option to model the data analysed. A similar approach is followed for the selection of the multi-objective optimisation algorithm. For this task, six techniques are tested and compared based on the hypervolume performance indicator to just then select the Non-dominated Sorting Genetic Algorithm II (NSGA-II) as the best option. Given this applied research focus on a real manufacturing process, real-world constraints and variables such as individual scrap price, scrap availability, tap additives and ambient temperature are used in the models developed here. A comparison with an equivalent EAF model from the literature showed a 13% improvement using the mean absolute error in the EAF energy usage prediction as a comparative metric. The multi-objective optimisation resulted in reductions in the energy consumption costs that ranged from 1.87% up to 8.20% among different steel grades and scrap cost reductions ranging from 1.15% up to 5.2%. The machine learning models and the optimiser were ultimately deployed with a graphical user interface allowing the melt-shop staff members to make informed decisions while controlling the EAF operation.

2025, IEEE Access

2025, Communications - Scientific letters of the University of Zilina

2025, Engineering, Technology & Applied Science Research

The primary aim of this laboratory study was to develop a Sustainable Roller-Compacted Concrete (S-RCC) that meets strength requirements by incorporating waste building materials. Specifically, waste Clay-Brick (CB) was used as a partial volume replacement for Fine Aggregate (FA) at two levels (15% and 30%) and for filler at 50%. The waste CB was manually broken with a hammer, further crushed using a mechanical crusher, and sieved to produce recycled sand. In addition to conventional water curing, three curing methods were evaluated: water spray, a liquid membrane-forming compound (Sika Antisol-WB), and damp burlap curing. The objective was to determine the most effective curing technique applicable in both laboratory and field settings. The results revealed that the S-RCC mixture containing 15% CB as FA replacement and 50% as filler replacement improved compressive, flexural, and tensile strength by 10.26%, 8.85%, and 7.75%, respectively, after 28 days of normal curing compared to the Reference Mixture (RM). Similarly, the mix with 30% CB as an FA replacement and 50% as a filler showed improvements of 6.29%, 5.42%, and 4.75% in compressive, flexural, and tensile strength, respectively. These enhancements are attributed to effective internal curing, as the highly absorbent nature of waste CB enables gradual water release, promoting hydration and improving the mechanical performance of this zero-slump concrete.

2025, JOM

In this study, nickel-boron (Ni-B) alloys were produced via a carbothermic reduction starting from boric acid (H 3 BO 3 ) with high-purity nickel oxide (NiO), charcoal, and wood chips in a direct current arc furnace. In electric arc furnace experiments, different starting mixtures were used, and their effects on the chemical compositions of the final Ni-B alloys were investigated. After the reduction and melting stages, Ni-B alloys were obtained by tapping from the bottom of the furnace. The samples from the designated areas were also taken and analyzed. The chemical composition of the final alloys and selected samples were measured with wet chemical analysis. The Ni-B alloys had a composition of up to 14.82 mass% B. The phase contents of the final alloys and selected samples were measured using x-ray diffraction (XRD). The XRD data helped predict possible reactions and reaction mechanisms. The material and energy balance calculations were made via the XRD Rietveld and chemical compositions. Nickel boride phases started to form 600 mm below the surface. The targeted NiB phase was detected at the tapping zone of the crucible (850-900 mm depth). The energy consumption was 1.84-4.29 kWh/kg, and the electrode consumption was 10-12 g/kg of raw material charged.

2025, BHM Berg- und Hüttenmännische Monatshefte

In the modern electric arc furnace (EAF), more than 40 % of energy comes from chemical sources by fossil fuels: natural gas is used in dedicated burners during the melting of the scrap, while lump coal (mainly anthracite) is added to the basket and pulverized coal is injected as a foaming agent. Within the frame of the European Research Fund for Coal and Steel (RFCS), the ongoing project GREENEAF (RFSR-CT-2009-004) is studying the possibility to replace coal and natural gas in EAF with char and syngas produced by biomass pyrolysis. The best pyrolysis conditions to obtain the proper syngas and char quality have been defined by laboratory tests using biomass available in the surrounding of the partners steel shops. Industrial trials have been performed in three different EAF plants. The results demonstrated the technical feasibility of the approaches, while the economical evaluation has showed the sustainability of replacing the coal with char from biomass in addition to environmental benefits due to CO 2 reduction.

2025, Jurnal Ilmiah Universitas Batanghari Jambi

The Electric Arc Furnace (EAF) prototype at the Morowali Metal Industry Polytechnic has the main component in the form of a transformer that generates heat actively. The increase in temperature that occurs in the transformer is caused by continuous loading. In addition, a significant and relatively high temperature rise in the transformer, can reduce the performance of the transformer. This research will design a transformer cooling system on the EAF prototype. The temperature of the transformer will be maintained at a certain temperature until there is no longer an increase in temperature due to loading. The wire-tube cooling system in the transformer uses water and transformer oil as the cooling medium. Regulating the flow rate of the water fluid in the copper pipe is expected to be able to further optimize the cooling process in the transformer. The results show that the design of the wire-tube cooling system is able to release the temperature of the transformer oil with a heat t...

2025, Materials

The utility of recycling some intensive industries’ waste materials for producing cellular porous ceramic is the leading aim of this study. To achieve this purpose, ceramic samples were prepared utilizing both arc furnace slag (AFS) and ceramic sludge, without any addition of pure chemicals, at 1100 °C. A series of nine samples was prepared via increasing AFS percentage over sludge percentage by 10 wt.% intervals, reaching 10 wt.% sludge and 90 wt.% AFS contents in the ninth and last batch. The oxide constituents of waste materials were analyzed using XRF. All synthesized samples were investigated using XRD to detect the precipitated minerals. The developed phases were β-wollastonite, quartz, gehlenite, parawollastonite and fayalite. The formed crystalline phases were changed depending on the CaO/SiO2 ratio in the batch composition. Sample morphology was investigated via scanning electron microscope to identify the porosity of the prepared ceramics. Porosity, density and electrical ...

2025

The lead-acid battery continues to be an indispensable energy storage solution owing to its robustness, cost-effectiveness, and wide-scale applicability in various sectors including automotive, power backup, and renewable energy. Among the numerous components of a lead-acid battery, lead connectors serve a critical role in maintaining efficient current flow between cells. The quality, consistency, and durability of these connectors are vital to battery performance and longevity. However, the traditional methods of manufacturing lead connectors, which often involve manually operated lead melting furnaces and uncontrolled pouring processes, are highly inefficient, laborintensive, and hazardous. They also result in inconsistent casting quality, thermal inefficiencies, and occupational safety risks. Drawing from these insights, the review proposes an innovative model: a semiautomated electric lead melting furnace with a tilting mechanism, which is designed to automatically fill the die in place. This system introduces a thermostat-regulated electric coil heating system that ensures uniform melting temperatures, while the tilting mechanism allows for controlled, spillage-free pouring of molten lead into the mold cavity. The incorporation of sensor feedback, automated valve control, and programmable operation sequences significantly improves efficiency and reduces human error. The proposed model, when compared against traditional systems and benchmarked using literature findings, offers several critical improvements. These include enhanced operational safety, reduced energy consumption, better temperature control, consistent output quality, reduced labor requirements, and scalability for small-scale industries. Additionally, the model aligns with the principles of Industry 4.0, enabling future upgrades such as IoT-based monitoring, predictive maintenance, and data-driven process optimization.

2025

The daily increase of various flicker source loads in power systems, has a lot of disadvantages like malfunctioning of electrical instruments and light flickers of the loads. Therefore, it is hardly demanded to determine the direction of flicker propagation that in turn helps to locate the flicker compensators. This paper has used an algorithm [1] for determining the flicker source direction. This method has been tested on a case study with two arc furnaces that are the main source of voltage flicker generation. The algorithm performance has been validated by the simulation results.

2025

This work presents the results of the incorporation of some industrial wastes from thermal processes in cement mortars. Employed wastes were generated in electric arc furnace (EAF) steelmaking and in steel foundry production. Namely, research with mortars containing EAF dusts and foundry sands and slags were conducted. Mechanical and environmental evaluation has been done, to compare the waste containing cement mortars samples with the normal one. The results indicated that the incorporation of these wastes generated in thermal processes in cement mortars does not affect significantly the mechanical properties, namely the flexural and compressive strength, and does not induce any relevant environmental impact when the materials have to be considered as waste, at the end of their life cycle. As a matter of fact, the cement mortar, if becoming a residue, may be considered as an inert one. The results of this work indicate that the incorporation of these wastes in cement mortars is an adequate waste management option.

2025, Journal of Cleaner Production

Among the actions proposed by the European Union for the implementation of Circular Economy is the use of waste as a secondary raw material (SRM). During the fusion of the scrap, a steel dust is generated, named Electric Arc Furnace Dust (EAFD). The EAFD is composed mainly of potentially leachable heavy metals, so is classified as "hazardous" waste. Around the world, approximately 70% of this waste is deposited in landfills, with a previous treatment through cement-based materials to prevent the metals' mobility. However, this action is not in accordance with the Circular Economy concept due to the greater use of resources and the loss of deposited metals. The present investigation analyses the use of EAFD as SRM in conventional mortar production for its use as a construction material. Different substitution percentages (25%, 50% and 100%) were used replacing siliceous filler by EAFD. The investigation analysed the behaviour of conventional mortars by tests of workability, compressive strength, water absorption by capillarity and leaching behaviour in granular and monolithic state. The results obtained indicate a slight improvement in mechanical behaviour with the incorporation of EAFD, the reason why its use as SRM in conventional mortars would benefit the construction industry and would encourage the Circular Economy. From an environmental point of view, the mechanisms of Pb fixation should be improved in granular state.

2025, Road Materials and Pavement Design

With a production of 101.4 million tonnes (MT) in 2017, India is the third largest steel producer in the world. Electric arc furnace (EAF) steel slag is the waste/by-product generated from steel-making industries that utilise electric arc furnace process of steel production. About 12 MT of steel slag is generated annually in India, but merely 20% is put to applications and the rest is indiscriminately dumped in nearby landfills. The primary objective of this study is to evaluate performance characteristics of open-graded friction course (OGFC) asphalt mixtures with varying proportions of EAF steel slag as the coarse aggregate ( > 2.36 mm). OGFCs are gaining popularity in the Indian highway sector owing to their superior hydraulic (high permeability), acoustic (noise-reduction) and frictional properties that contribute towards improved road safety. The level of research on the use of EAF steel slag in OGFC is still very limited, especially in developing countries like India. Ten OGFC mix designs were investigated containing five percentage substitutions of coarse natural aggregates (0%, 25%, 50%, 75% and 100%) with the EAF steel slag and two modified asphalt binders (polymer and crumb rubber modified). Static creep test, dynamic creep test, Hamburg wheel tracking test, indirect tensile stiffness modulus test, and indirect tensile fatigue test were performed to evaluate rutting and fatigue performance of steel slag-OGFC mixtures. Results of the study reveal that the EAF steel slag-OGFC mixtures showed superior performance compared to control mixtures. The steel slag-OGFC mixtures up to 75% substitution presented the best results with both binder types.

2025, Journal of Building Engineering

Research on sustainable concrete has drawn scientist's attentions on industrial by-products and wastes. Thus, consumption of raw materials would be diminished. In this study alkali activation of electric arc furnace slag (EAFS) was studied with a comprehensive test program. Different silicate modulus, sodium concentrations, curing conditions, curing temperatures and relative humidity condition variables were selected. Their effects on mechanical and micro structural behaviors of the mortar were investigated through SEM -XRD analyses. Result of this study, EAFS was activated with sodium hydroxide and sodium silicate solutions. Test results also revealed that increase in relative humidity, curing temperature and curing time had positive effects on strength parameters due to diminishing micro cracks and altering hydration reactions. With the current study utilization of EAFS is thought to be successfully disposed.

2025, IOP Conference Series: Materials Science and Engineering

Initially, the carbon content was reduced by mixing "the iron" with metallic ingots in ceramic crucibles/melting pots, with external heat input. As time went by the puddling procedure was developed, a procedure which also assumes a mixture with oxidized iron ore. In 1856 Bessemer invented the convertor, thus demonstrating that steel can be obtained following the transition of an air stream through the liquid pig iron. The invention of Thomas, a slightly modified basic-lined converter, fostered the desulphurization of the steel and the removal of the phosphate from it. During the same period, in 1865, in Sireuil, the Frenchman Martin applies Siemens' heat regeneration invention and brings into service the furnace with a charge composed of iron pig, scrap iron and iron ore, that produces a high quality steel . An act worthy of being highlighted within the scope of steelmaking is the start-up of the converter with oxygen injection at the upper side, as there are converters that can produce 400 tons of steel in approximately 50 minutes. Currently, the share of the steel produced in electric arc furnaces with a charge composed of scrap iron has increased. Due to this aspect, the electric arc furnace was able to impose itself on the market.

2025, Energy Policy

The energy used to produce austenitic stainless steel was quantified throughout its entire life cycle for three scenarios: (1) current global operations, (2) 100% recycling, and (3) use of only virgin materials. Data are representative of global average operations in the early 2000s. The primary energy requirements to produce 1 metric ton of austenitic stainless steel (with assumed metals concentrations of 18% Cr, 8% Ni, and 74% Fe) is (1) 53 GJ, (2) 26 GJ, and (3) 79 GJ for each scenario, with CO 2 releases totaling (1) 3.6 metric tons CO 2 , (2) 1.6 metric tons CO 2 , and (3) 5.3 metric tons CO 2 . Thus, the production of 17 million metric tons of austenitic stainless steel in 2004 used approximately 9.0 Â 10 17 J of primary energy and released 61 million metric tons of CO 2 . Current recycling operations reduce energy use by 33% (4.4 Â 10 17 J) and CO 2 emissions by 32% (29 million tons). If austenitic stainless steel were to be produced solely from scrap, which is currently not possible on a global level due to limited availability, energy use would be 67% less than virgin-based production and CO 2 emissions would be cut by 70%. The calculation of the total energy is most sensitive to the amount and type of scrap fed into the electric arc furnace, the unit energy of the electric arc furnace, the unit energy of ferrochromium production, and the form of primary nickel.

2025, Water, Air, & Soil Pollution

Electric arc furnace (EAF) dust and slag, materials which contain high metals in their composition, were improperly disposed in an industrial steel mill site between 1963 and 1999. Previous environmental investigations identified anomalous concentrations of metals in local groundwater but failed to relate these abnormalities to the disposed material or to natural geochemical processes. Aiming to identify the origin of such abnormalities, exploratory and spatial data analysis (EDA-SDA) method was applied on a hydrogeochemical data set obtained through 5 sampling campaigns in 32 groundwater monitoring wells installed upstream and downstream of the area impacted by the steel mill activities. Boxplot class-based and Eh vs. pH maps of physicochemical log-transformed data identified that wells located under the influence of EAF slag deposits in topographic hollows had lower Eh potential and increased electrical conductivity and pH, when compared to wells in the topographical nose of the surveyed area. Metal distribution maps showed that Al, Ca, K, Mg, Na, and Sr were consistently higher in topographic hollows while concentrations of Co, Cu, Cr, and Li were higher near the former steel-making plant, located in the topographical nose. Ba, Fe, Mn, and Zn, important indicators of EAF slag and dust, were observed in both topographic settings. Variable clustering was able to capture the relations among metals and thus validate the log-normalized data structure to be used into wells clustering. Clustering through the mclust algorithm carried out for two and three clusters allowed the distinction among localities that received an input of metals from dust or slag and those not influenced by either residue. This paper demonstrates that EDA-SDA is an effective method to identify areas under the influence of contamination from industrial activities from areas not affected by anthropogenic contamination.

2025, Journal of Mining and Metallurgy, Section B: Metallurgy

The paper gives a common outline about the known recycling techniques from electric arc furnace dusts and describes an investigation of a pyrometallurgical process for the recovery of zinc and iron from electric arc furnace dusts (EAFD). In the waelz process, the reduction of zinc and iron from the waste oxides using solid carbon (lignite coal) was studied. In the reduction experiments; temperature, time and charge type (powder and pellet) were investigated in detail. It was demonstrated that zinc and iron recovery (%) increases with increasing temperature as well as time. Pelletizing was found to be a better method than using the powder as received for the zinc recovery and iron conversion (). In the calcination (roasting) process, crude zinc oxide, which evaporated from non-ferric metals were collected as condensed product (crude waelz oxide), was heated in air atmosphere. Lead, cadmium as well as chlorine and other impurities were successfully removed from crude waelz oxide by th...

2025, Ironmaking & Steelmaking

Electric furnace dust and filter cake collected from a stainless steel plant as well as EF dust collected from a ferrochrome plant were characterised. Electric furnace dusts consist of very fine particles, from which Cr(VI) can be leached by shallow groundwater. When heated in air H 2 O, CO 2 , SO 2 , SO 3 , fluorine, calcium and silicon are expelled from these materials, while metallic particles oxidise. The main phases present in the stainless steel plant dust are the (Mg,Fe,Mn,Cr) 3 O 4 spinel phase, quartz, Ca(OH) 2 and nickel. The coarse fraction of ferrochrome dust mainly contains chromite and partly altered chromite, quartz and carbon, while the main components of the fine fractions of ferrochrome dust are chromite, SiO 2 , ZnO, NaCl and Mg 2 SiO 4 . CaF 2 is the major phase in the filter cake. Cr(VI) containing phases are possibly generated at the top of the submerged arc furnace or in the off gas duct, as Cr(VI) is found on the surface of the dust.

2025, Civil Engineering Infrastructures Journal (CEIJ)

This paper analyzes how feasible it is to use electric arc furnace slag as coarse aggregate, and blast furnace dust as fine aggregate in the manufacture of hot asphalt concrete for roads. Three mixtures were designed using the Ramcodes methodology, the M1 mixture of control with conventional materials, the M2 mixture replacing 50% and the M3 mixture replacing 100% of the conventional aggregates, which were submitted to tests to evaluate the susceptibility to moisture damage and plastic deformation, as well as others to determine the resilient modulus and the fatigue laws for each type of mixture. The mixtures with EAF and BFD presented better mechanical characteristics than the mixture with natural aggregates, met the acceptance requirements and the results of the performance tests are within the required requirements.

2025

Over the last decades, there is a growing demand to reduce the Portland Cement (PC) content and increase the amount of various supplementary cementitious materials (SCMs) used in concrete mixture to help reduce the embodied CO 2 (ECO 2) of concrete and more generally, the environmental impacts of concrete industry. The main objective of this paper is to assess the CO 2 emissions associated with concrete production using various combinations of SCMs as per EN197-1 and further to develop concrete mixes with reduced ECO 2 and enhanced durability. The results indicate that the ECO 2 reduction in the composite cements is proportional to the substituted amount of PC by the SCMs in the concrete mix. In addition to the environmental benefits generated by the use of high content of SCMs as substitute of PC, the obtained results reveal a significant long-term improvement in strength properties and durability performance of composite cement concretes.

2025, Computational problems of electrical engineering

It is the first paper where the electrical mode of an arc furnace (AF) is proposed to be considered as a state change. This work also proposes a methodology for calculating the time values of the probabilities of these states. The methodology is based on the representation of state-change processes by the Markov model of continuous time, discrete state (CDS) stochastic processes. The state of electrical mode in each phase of an arc furnace is identified by the value of arc current that can be set for a given melting period, may be in the range of permitted deviations, or may get to the range of large operational or emergency deviations. Assuming that the system goes from state to state under the action of the Poisson flows of events, the concept of intensity of disturbance flows, and the intensity of flows of control actions are introduced. This makes it possible to form a system of Kolmogorov differential equations to change the state probabilities of the AF electrical mode. The solution of the system results in obtaining time dependencies of change in state probabilities. When analyzing graphs of changes over time in the probabilities of AF electrical mode states, it is possible to choose the desired intensity of the flow of control actions, which ensures that the electrical mode is in a given state under the action of the corresponding disturbance flow.

2025, Congreso Internacional de Metalurgia y Materiales

2025, Environmental Science & Technology

Increasing amounts of municipal solid waste incineration (MSWI) residues are treated prior to landfilling or reuse. In Japan, electric arc melting is used for bottom ash vitrification that generates a glasslike slag. The objective of this paper was to assess this pretreatment technique with respect to its effect on metal mobility and metal content. Both bottom ash and slag were sampled and analyzed on total solids (TS), fixed solids (FS), particle density (F P ), specific BET surface area, particle size distribution, and total element content. A six-step wet sequential extraction procedure was used for assessing metal mobility. The results were qualitatively verified by scanning electron microscopy. The major conclusion was that the availability of various metals was affected differently by electric arc vitrification. Metals were solidified, stabilized, and/or separated from the slag. The mobility of Cr, Cu, Zn, Pb, and Ca was reduced. In slag, major fractions of these elements were found in moderately reducible phases or in the residual slag lattice. The approximately three-fourths of Pb [174 ( 7 mg (kg of FS) -1 ] and half of Zn content [676 ( 352 mg (kg of FS) -1 ] were most likely removed from bottom ash through evaporation. The total content increases of Al, Cr, Ni, and Cd (51 ( 3, 621 ( 27, 138 ( 19, and 99 ( 32%, respectively) were probably caused by the wear of furnace refractories.

2025, Journal of Sustainable Metallurgy

The transition to hydrogen-based reduction processes within the iron and steelmaking industry will generate new types of slag compositions that require valorization routes. Using slags as supplementary cementitious materials (SCMs) addresses the carbon dioxide emissions of the cement industry since the SCM requires neither calcination nor clinkering. Conventionally, ironmaking slags from the blast furnace (BF) are recycled as SCMs, i.e., ground granulated BF slag (GGBS). Ideally, future slags from electric arc furnaces (EAFs) operating on hydrogen-based direct reduced iron should be valorized analogously. Since the hydrogen-based process route is not yet realized in an industrial scale, the literature lacks data to support this valorization route, and additionally, literature on scrap-based EAF slags is scarce. Therefore, the present study aimed to offer insights into the utilization of ore-based EAF slags as SCMs based on an industrial slag sample from an EAF operating on hot briquetted iron. The slag was remelted, modified, and water-granulated in laboratory scale, and its performance as an SCM was compared to water-granulated ladle slag and two commercial GGBS. The results showed promising reactivities measured using the R 3 isothermal calorimeter-based testing protocol. Based on the comparison to GGBS, the study indicated that generating reactive and appropriate SCMs from EAF slags will partly be a challenge in balancing the crystallization of the MeO-type solid solution rich in magnesia and addressing the iron oxide content in the amorphous phase. The contributing editor for this article was Sharif Jahanshahi.

2025

A series of microalloyed aluminium-killed steels stabilized with titanium, were made by means of the route of electrical arc furnace, vacuum degasser, secondary refinement and steel solidified into a continuous casting process. The resultant samples were hot rolling at 1100 - C, cooled in air down to 650 - C during 30 minutes, and cooled to room temperature. The resultant

2025, IEEE Transactions on Industry Applications

2025, Bulletin of Electrical Engineering and Informatics

Voltage flickers and harmonics are power quality (PQ) problems in the electric system during a variation and arc furnace (AF) adaptability. AF creations must determine a harmonic and flicker. This article evaluates complex AF systems. This article presents a newly established time domain (TD) static become to on an AF's V-I attributes (VIA). Static arc configurations are useful for harmonic analyses, but dynamic methods are needed for PQ studies, especially voltage flicker analysis. The MATLABbased dynamic AF configuration is simulated for four different configurations. A response with configurations 1 and 4 varies from the real AF outcomes. The simulation results and numerical finding shows that configurations 2 and 3 are much more appropriate and produce better results for minimum 3 rd harmonics for arc current, arc voltage, and point of common coupling (PCC) voltage. The novelty of this configuration is that the energy transferred to the load by the AF during the cycle of operation has been identified, making the developed scheme more reliable and dependent on the load's operational conditions. After that, effective applications of these configurations and other configurations' accuracy should be clarified.

2025, 2006 IEEE International Symposium on Industrial Electronics

This paper presents a new approachfor the dynamic compensation offlicker and harmonics in arc furnace power systems based on the UPFC. An arc furnace induces different kinds of disturbances caused by the harmonics and transient over voltage during the melting of scraps. Dynamic compensation is needed to improve the efficiency ofprocess and to mitigate the disturbances caused to the network. The arc furnace load actually looks like a voltage source of harmonics behind a series of impedance consisting of the secondary cables to the electrodes. The UPFC with series active compensation capability opposed to variations ofthe arc resistance and suppress voltage flicker at the source. The design and control strategy of the UPFC based on the instantaneaous power calculation are detailed by this paper. A typical arc furnace and UPFC model has been implemented in digital simulator to demonstrate how the UPFC can be controlled to take care ofall disturbances.

2025

This work aims to describe the designing and construction of a 10 kg laboratory scaleElectric Arc Furnace equipped with a system for measurement of electrical parameters.The EAF is used in a resear ...

2025, Journal of Environmental Chemical Engineering

Fenton oxidative degradation of methylene blue and acid blue 29 dyes using sulfuric acid-activated slag of the steel-making process,

2025, IOP Conference Series: Materials Science and Engineering

Sulphated electric arc furnace slag (S-EAFS) was obtained through a facile chemical and thermal treatment method. The S-EAFS was evaluated as a Fenton-like catalyst for the oxidative degradation of reactive black 5 (RB5). The S-EAFS was characterized by XRD, SEM-EDX and nitrogen adsorption analysis. The highest RB5 degradation efficiency obtained in this study was above 90% which was maintained across seven successive cycles with minimum iron leaching. This was achieved at a RB5 concentration of 0.15 gL -1 (50 ppm) with 8 mM of H 2 O 2 and a pH of 4.5. Characterization revealed that the presence of sulphated groups (SO 4 2-) within the EAFS improved the surface acidity of the material and corresponded to an increase in the catalytic activity for the degradation of RB5 at mild pH.

2025, Journal of Environmental Management

In this work, an activated electric arc furnace slag (A-EAFS) was investigated as an effective Fenton catalyst for the photodegradation of methylene blue (MB) and acid blue 29 (AB29). Fourier transform infrared spectroscopy and UVevisible absorption analyses indicated that A-EAFS offers additional Fe 3 O 4 because of the changes in the iron oxide phase and the favorable response to visible light. It has been found that the highest degradation efficiency can reach up to 94% for MB under optimal conditions of 1 g L À1 of A-EAFS, 20 mM H 2 O 2 , and pH 3. The optimal conditions for AB29 were 0.1 g L À1 A-EAFS, 4 mM H 2 O 2 , and pH 3 to reach 98% degradation efficiency. Visible light enhanced the degradation of both dyes. In addition, A-EAFS, could be easily separated magnetically, exhibited good chemical stability after seven successive photodegradation cycles.

2025, Journal of the Taiwan Institute of Chemical Engineers

This study aims to explore the feasibility of using iron slag derived from an electric arc furnace (EAFS) as a catalyst to degrade Reactive Black 5 (RB5). Raw EAFS (R-EAFS) subjected to 0.1 M NaOH solution treatment and thermal treatment was denoted as activated EAFS (A-EAFS). A-EAFS was characterized and examined for its capability to degrade RB5 in a dark-batch reaction under different catalyst dosages (0.01-0.06 g), H 2 O 2 dosages (2-12 mM), initial pH values (2-7), initial concentrations (25-150 ppm), and reaction temperatures (303-323 K). The optimal conditions (94% within 60 min) for RB5 degradation were 0.2 g L -1 , 8 mM H 2 O 2 , and pH 3. The degradation rate of A-EAFS for RB5 exceeded 94%, which was higher than that of R-EAFS. Recycling of A-EAFS after 10 reuses suggested that this stability is ascribed to the regeneration of the major constituent's ferrous ion magnetite and maghemite to decompose H 2 O 2 into hydroxyl radical catalytically. Therefore, A-EAFS is an alternative heterogeneous catalyst in the abatement of organic dyes from polluted water through a heterogeneous Fenton-like reaction.

2025, IOP Conference Series: Materials Science and Engineering

This work presents the iron oxide recovery from electric arc furnace slag with different temperature and time using acid leaching method. The results showed that formation of iron oxide from electric arc furnace (IO-EAFS) was influenced by the temperature and time of heating. This is evidenced by constant acid concentration and liquid to solid ratio, 5 hours of heating time was exhibited the highest amount of iron ion in extracted solution. The maximum of iron extract in heating temperature was at 100 °C. Throughout the characterization using Scanning Electron Microscopy (SEM), the iron oxide illustrated the microstructures were agglomerates predominantly with irregular shapes and XRD results further colobrated the presence of hematite combined with other metal oxide exists in the IO-EAFS. From the TGA analysis, it was identified that the recovered iron oxide was totally decomposed at 525°C. This results indicate that electric arc furnace slag is potential material of iron oxide for...

2025

a 40 km de Guayaquil, que está en proceso de puesta en marcha. En Alóag, durante un período del ano 2016, se observaron algunos defectos superficiales en barras de refuerzo de hormigón. Luego de estudios metalográficos, se encontró que algunos de llos se originaban en pinholes. Se implementó un detallado control de las palanquillas mediante el mecanizado de las cuatro caras en cortes transversales de las mismas. Se tomaron medidas para superar el problema, teniendo en cuenta la calidad de la carga metálica, el proceso de desoxidación durante el sangrado y en el horno cuchara; el caudal y la distribución del aceite y aspectos relacionados. En el trabajo se detallan los estudios realizados y las medidas tomadas para minimizar el problema. La acería de Alóag incluye un patio de chatarra con una fragmentadora, un horno eléctrico de

2025

The source identification of Polychlorinated Dibenzo-p-Dioxins (PCDDS) and Polychlorinated Dibenzo-p-Furans (PCDFS) in West Africa has been the most difficult problem to tackle due to the unavailability of the facility to analyze the samples and high cost of sampling equipment. This study is based only on the determination of the PCDDS/PCDFS at cement industries in Nigeria, Cameroun and Benin Republic. The sampling adopted the gravimetric (method) principle for extractive source analysis using Paul Gothe Bochum stack sampler and PCDDS/PCDFS traps from Concept Life Sciences Laboratory in the UK. The traps were exposed using the standard guidelines and transported back to the same laboratory for analysis in the UK. The parameters recorded during PCDDS/PCDFS sampling are stack temperature, ambient temperature, pressure, flow rate and moisture content at isokinetic mode. The PCDDS/PCDFS results from different cement industries are: Nigeria (Plant A = 0.0209 ng/TEQ/Nm3; Plant B = 0.0316 ng/TEQ/Nm3), Cameroun (Plant C = 0.0062 ng/TEQ/Nm3; Plant D = 0.0143 ng/TEQ/Nm3) and Benin Republic (Plant E = 0.0101 ng/TEQ/Nm3). All the results recorded are below Nigerian emission standards and international emission standards. By comparing the standards, the disparity between Nigeria and other international countries is high while other neighbouring countries do not have the PCDDS/PCDFS standard. This might be due to typographical errors or the paucity of data for PCDDS/PCDFS from different sources to review the standards. Based on the nature of PCDDS/PCDFS on humans and ecosystems, the major concern is long-range transmission and accumulation in the food chain and animals. From this study, it is observed that the determination of PCDDS/PCDFS from other sources will be a great achievement for the implementation of reduction mechanism strategies. It is being recommended that the Nigerian Government should carry out a national emission inventory along with neighbouring countries. Also, existing standards and regulations on open burning, industries, mobiles and dumpsites should be strictly implemented.

2025

Due to operational conditions and locations, BOF suffers variations in important parameters whose effects on the liquid bath are usually neglected. The present paper investigated two aspects: inner BOF pressure and oxygen temperature in the stagnant reservoir. The results have shown that oxygen temperature changes properties like density and velocity but has small influence on jet penetration. The BOF inner pressure has significant influence on jet penetration and creates a new challenge regarding nozzles dimensions considering overexpanding and underexpading jets.

2025, https://www.fini-unm.si/en/international-conference/proceedings/

The circular economy (CE) framework is crucial for promoting resource efficiency and minimizing waste, but it cannot achieve its sustainability goals alone. To achieve a truly sustainable future, broader social, environmental and economic aspects need to be taken into account. Rather than separating biological and technological cycles, as the CE principles are depicted in the Ellen MacArthur Foundation's butterfly diagram (EMF, 2017), we propose an integrated approach that prioritises environmental aspects and includes a conceptual framework, socioeconomic changes and implementation processes. It is crucial to re-evaluate the environmental aspects and strengthen their importance within the CE framework. Within this concept we present the case of iron, the most widely used metal, widely available compared to others and has been an essential part of societal development for more than 5,000 years. With its abundance, safety and electrochemical properties, iron is an ideal material for low-carbon energy technologies. We discuss how advanced iron-based technologies have a high potential to be successfully integrated into the CE, we evaluate different electrochemical energy storage systems and present advances in thermochemical Fe-Cl cycles for hydrogen production. An innovative thermal system for hydrogen production based on the thermochemical Fe-Cl cycle was evaluated in a life cycle assessment (LCA) study and shows the importance of choosing sustainable energy sources to minimise environmental impact. Sustainable production methods for iron are also analysed to demonstrate their potential to reduce the carbon footprint of the iron and steel industry. Finally, efforts should focus on minimising environmental impact and optimising resource recovery.

2025, 2017 International Conference on Intelligent Computing, Instrumentation and Control Technologies (ICICICT)

Development on a country is based on its industrialization and infrastructure; steel is used as a vital part of any building infrastructure, the process of steel manufacturing using electric arc furnace (EAF) introduces several power quality disturbances, in this paper, characteristic modeling of electric arc furnace and its effects on power quality is investigated. Several EAF models are modeled and reviewed from power quality assessment. Voltage flicker, Harmonics and Inter harmonics arises in an electrical network due to the non-linear nature of EAF operation. Time-domain modeling and frequency domain modeling of an EAF is simulated using MATLAB/ SIMULINK and PSCAD simulation software.

2025

The article presents the results of study of the properties of GF cements prepared from standard white cement clinker. The properties of GF cements based on white cement clinker are fully analogous to those of GF cements based on conventional (grey) Portland cement clinker. The effect of reduced content of Fe 2 O 3 and of the significantly lowered content of the C 6 A x F y phase in white GF cement has no discernible influence on the properties. White GF cement has equal or better refractory properties compared to those of alumina cement (with a low content of Al 2 O 3 ).