• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2001년도 가을 학술발표회 논문집
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• pp.669-674
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• 2001

Electric Arc Furnace Dust (EAF Dust) Is residual dust produced during the manufacturing of metal products from heavily heated electric arc furnace. Many researches have focused on recycling and reusing EAF Dust for industrial and construction purposes. However, most of these researches were aimed at obtaining useful heavy metal powders by treating toxic metallic materials in EAF Dust. Also, few researches dealt with using EAF Dust as admixture in concrete mixture (i.e., slag dust). In this study, EAF Dust is used as admixture in concrete mixture content considering economical feasibility and construction applicability. The concrete specimens mixed with EAF Dust is then tested in compression and tension to study its strength and ductility as well as its failure mechanism. The compression and tension (by split cylinder test) test results are compared to the results from the specimens without EAF Dust to understand the chemical stability and mechanical characteristic of concrete specimens with EAF Dust. For the experiment, 6 types of admixture added concrete were studied: ⑴Combination of EAF Dust and blast-furnace slag in 1 to 1 ratio, ⑵Combination of EAF Dust and blast-furnace slag in 1 to 2 ratio, ⑶EAF Dust only, ⑷blast-furnace slag only, ⑸fly ash only, and ⑹no admixture. The experimental results show that the strength of EAF Dust added specimen has lower early age strength but higher 28 day strength when compared to other specimens. Also, the Elastic Modulus of EAF Dust is higher(28 days) than other specimens. The study results prove that EAF Dust can be used as an effective admixture in concrete for specific usages.

• 자원리싸이클링
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• 제24권6호
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• pp.31-37
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• 2015

철강산업 부산물 중 고로슬래그는 시멘트혼화재로 재활용되고 있지만 제강 슬래그들은 주로 골재로서 활용되고 있다. 본 연구는 전기로 산화슬래그를 대상으로 용융상태에서 철을 환원시켜 개질한 후 물로 급랭하여 제조된 비정질 슬래그를 시멘트 혼화재로 활용하고자 하였다. 개질된 전기로 산화슬래그는 고로수쇄슬래그 보다 분쇄성이 높았으며, 고로슬래그와 개질산화슬래그를 혼합하여 제조한 슬래그 시멘트의 모르타르 실험결과 고로슬래그에 대한 개질산화슬래그 대체율 20%까지는 비교시험체의 98%에 해당하는 압축강도 특성을 나타냈다.

• 대한전기학회논문지:전력기술부문A
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• 제50권2호
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• pp.90-95
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• 2001

Electric arc furnaces (EAFs) has a process to cause the degradation of the electric power quality such as voltage flicker. In order to adequately understand and analyze the effects on the power system from these loads, obtaining an accurate representation of the characteristics of the loads is crucial. In this paper, a mixed chaotic EAF model to represent the low frequency and high frequency variations of the arc current respectively has been proposed. The Lorenz system may contribute to the low frequency components of arc current and the logistic equation may contribute to the high frequency components, and the proposed mixed model will be a combination of both Lorenz and logistic model. The concept of chaotic parameters, such as chaotic resistance, inductance of admittance has been also proposed for the characterization of arc furnace operation and the highly nonlinear physical processes. The power quality indices are calculated from the simulated waveforms and compared with the actual power quality indices statistics in order to illustrate the model's capabilities.

• 한국세라믹학회지
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• 제18권4호
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• pp.247-256
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• 1981

Silica bricks had been in arc-furnace roofs of various sizes and steelmaking practices. The resulting materials were examined with reference to mineral and chemical changes. Silica bricks develope definite zones while in service. These zones represent a concentration gradient through the brick that results from the thermal gradient across the brick and from the furnace atmosphere. There are major brick losses by spalling as well as by melting of the hot-face surface in an iron-oxide rich liquid.

• Journal of Electrical Engineering and Technology
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• 제1권2호
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• pp.153-160
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• 2006

This paper presents a new compensating system, which consists of a shunt active filter and passive components for mitigating voltage and current disturbances arising from an Electric Arc Furnace (EAF). A novel control strategy is presented for the shunt active filter. An extended method based on instantaneous power theory in a rotating reference frame is developed for extraction of compensating signals. Since voltages at the point of common coupling contain low frequency interharmonics, conventional methods cannot be used for dc voltage regulation. Therefore, a new method is introduced for this purpose. The passive components limit the fast variations of load currents and mitigate voltage notching at the Point of Common Coupling (PCC). A three-phase electric arc furnace model is used to show power quality improvement through reactive power and harmonic compensation by a shunt active filter using the proposed control method. The system performance is investigated by simulation, which shows improvement in power quality indices such as flicker severity index.

• 조명전기설비학회논문지
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• 제20권8호
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• pp.48-53
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• 2006

제철소에서 사용되고 있는 전기로는 전력계통에 전압 변동을 일으키며 시간에 따라 변하는 비선형 부하이다. 플리커는 전압 변동의 크기에 따라 램프의 방출 변화에 의한 인간의 지각 효과로 정의된다. 플리커 레벨은 전압 변동의 크기, 주파수 및 기간에 의해 결정된다. 본 논문에서는 전기로 부하로 인한 154[kV] 시스템에서의 전압 변동 문제를 측정하고, 플리커 저감을 위한 SVC 적용 결과를 분석하고, IEC 61000-3-7에 의하여 플리커를 평가하였다.

• 한국도로학회논문집
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• 제17권1호
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• pp.25-33
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• 2015

PURPOSES : This paper, presents the results of a laboratory study aimed to verify the suitability of a particular type of Electric Arc Furnace (EAF) steel slag to be recycled in the lithic skeleton of both dense graded and porous asphalt mixtures for flexible pavements. METHODS : Cyclic creep and stiffness modulus tests were performed to evaluate the mechanical performance of three different asphalt mixtures (dense graded, porous asphalt, and stone mastic) prepared with two types of EAF steel slag. For comparison purposes, the same three mixtures were also designed with conventional aggregates (basalt and limestone). RESULTS : All the asphalt mixtures prepared with EAF steel slag satisfied the current requirements of the European standards, which support EAF steel slag as a suitable material for flexible pavement construction. CONCLUSIONS : Based on the experimental work, the use of waste material obtained from steel production (e.g. EAF steel slag) as an alternative in the lithic skeleton of asphalt mixtures can be a satisfactory and reasonable choice that fulfills the "Zero Waste" objective that many iron and steel industries have pursued in the past decades.

• 한국구조물진단유지관리공학회 논문집
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• 제16권5호
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• pp.40-48
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• 2012

이 연구에서는 철강 공정에서 발생되는 전기로 산화슬래그 골재를 사용한 철근콘크리트 보의 전단 성능을 평가하였다. 이를 위하여 총 6개의 단순지지형 실험체를 제작하여 전단실험을 수행하였다. 주요 실험변수는 골재의 종류와 전단철근의 유무로 하였다. 실험체는 전단경간비가 2.5, 폭 200mm, 유효깊이가 300mm인 직사각형 단면으로 4점가력을 받도록 계획하였다. 기존 강도식을 사용하여 실험체의 전단강도를 예측하였으며, 전단해석모델을 사용한 유한요소해석을 수행하여 전기로 산화슬래그 골재를 사용한 실험체의 전단거동을 예측하였다. 실험결과로부터, 전기로 산화슬래그 골재를 사용한 실험체의 전단 성능은 천연골재를 사용한 실험체와 서로 유사한 것을 확인할 수 있었다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 The 6th International Symposium of East Asian Resources Recycling Technology
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• pp.393-397
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• 2001

The innovatory process, that is the direct separation and recovery of the iron and zinc metals contained in the high temperature exhaust gas generated from the electric arc furnace fer the inn scrap melting and/or the dust treatment, has been proposed. This proposed process consists of the moving coke bed filter that is directly connected to the electric furnace, and the following heavy metal condenser. The exhaust gas passes through the filter and the condenser right after exhausting from the electric furnace. The moving coke bed filter is being controlled at about 1000℃ and collects iron and slag components contained in the high temperature exhaust gas. Heavy metals such as zinc and lead pass through the filter as vapor. Based on the thermodynamic considerations, the iron oxide and the zinc oxide are reduced in the filter. The solution loss reaction rate is comparatively low at about 1000℃ in the coke bed filter by the analysis using the mathematical simulation model. The heavy metal condenser is installed in the position after the coke bed filter, and rapidly cools the gas from about 1000℃ to 450℃ by a full of the cooling medium like the solid ceramic ball in addition to the cooling from the wall. The zinc and lead vapor condense and separate f개m the gas in a liquid state. The investigation of the characteristics of the exhaust gas of the commercial electric arc furnace, the fundamental experiments of the laboratory scale and the bench scale ensured the formation of this proposed process. A small-scale pilot plant examination is carrying out at present to confirm the formation of the process. It is certain that the dust generation of the electric arc furnace is extremely decreased, and it can save the energy consumption of usual dust treatment processes by the realization of this process.

• 한국대기환경학회지
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• 제22권1호
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• pp.35-41
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• 2006

The steel foundries with electric arc furnaces handling metal scraps have recently gained an attention as a potential source of dusts. The present study focuses on the analysis of dust emissions and removals during furnace charging and melting processes by commercial CFD software named FLUENT. A body fitted grid system consisting of 880,000 meshes was first generated by Gambit for the electric arc furnace with the capacity of 60 ton/cycle and then FLUENT was invoked to solve the corresponding NavierStokers equation for the momentum, temperature and dust concentration. The entire processes from metal charging to metal melting were simulated to investigate the unsteady behaviors of fluid flows and dust concentrations. The model simulation results showed that as the top of the electric arc furnace opened for metal charging, hot plumes bursted out from the furnace rose strongly by buoyance and escaped mostly through the main hood. Therefore, the capacity of main hoods determined the vent efficiency in the metal charging process. As the furnace was closed after the metal charging and the metal melting processes was followed, the hot flow stream stretching from the furnace to the main hood was dissipated fast and the flow from the inlet of the bottom of the left hand side to the main and monitoring hoods constituted the main stream. And there was only a slow flow in the right hand side of the furnace. Therefore, the dust concentrations were calculated higher in the left hand side of the furnace, which was consistent with observations.