• Journal of the Korean Institute of Intelligent Systems
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• v.18 no.6
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• pp.821-825
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• 2008

A fuzzy control algorithm is used to weigh alloy metal into electric arc furnace and implemented by using ladder program for programmable logic controller, where weight error and its derivative are used for input variables and vibration amplitude of alloy bin is used for output variable. Proposed fuzzy control algorithm is applied to the plant and results in higher measuring accuracy as well as faster measuring term than conventional on-off control system.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2019.05a
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• pp.170-171
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• 2019

The EMP slip rate was compared with the general concrete using the electric arc furnace slag as an aggregate. Experimental results show that the shielding rate of concrete specimens using electric arc furnace slag increases. It is considered that the shielding rate is increased due to the high Fe content in the components of the electric arc furnace slag aggregate.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2013.11a
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• pp.164-165
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• 2013

This study is on the performance evaluation of concrete being used the CaMg based low carbon cement(LCC) as a binder and the rapidly cooled electric arc furnace oxidizing slag(EAF slag) as a fine aggregate. When using the sand as a fine aggregate, compressive strength of the concrete using LCC, as a binder, was reduced 9% comparing with that of OPC concrete. However, when using the EAF slag as a fine aggregate, the compressive strength was increased by 9%. We found that combination LCC and EAF slag contribute to the strength properties of concrete.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2013.05a
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• pp.318-320
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• 2013

The spherical bead manufactured by rapidly cooling process shows high density of 3.64g/㎤, high unit volume weight of 2.6kg/l, and high solid volume of 71%. When it applies to the grouter, it is possible to obtain even high fluidity with only a small amount. This study, focusing the grouter using a rapidly-cooled electric arc furnace oxidizing slag(RC-EAFS), deals with the properties of flow and setting time in fresh state, compressive strength and length variation at 1, 3, 7 and 28 curing day in hardened state. As the results, even though the grouter with RC-EAFS shows comparative low strength, it will be possible to development the competitive product due to the properties of increasing flow and low cost.

• Journal of the Korean Recycled Construction Resources Institute
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• v.3 no.1
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• pp.65-71
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• 2007

Since pop-outs are occurred recently on concrete surface occasionally, it is needed to find out accurate causes and to suggest appropriate methods. On this study, it is investigated the occurrence mechanism of pop-outs caused by electric arc furnace Oxidizing slags as fine aggregate for concrete. As a result, it is investigated the cause of pop-outs that extremely small quantities of free CaO and free MgO in the electric furnace slag react with water to produce $Ca(OH)_2$ and $Mg(OH)_2$, so that their volumes are expanded and erupted about two times. As a resolution, it is needed to remove the potential cause of expansion by replacing the deteriorated concrete section up to the depth to secure the safe of structural element with repairing polymer mortar, especially more than 50MPa.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.20 no.6
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• pp.35-42
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• 2006

Large steel industries have nonlinear loads including electric arc furnaces. These nonlinear loads generate harmonic currents and create distortions on the sinusoidal voltage of the power system. This paper provides an in depth analysis on harmonics field measurement of the electric arc furnace loads, adding a single-tuned filter at the customer bus for reducing harmonic distortion and harmonics assessment by the international harmonic standards IEC 61000-3-6 and IEEE Std. 519. The EDSA program was used as a simulation tool for the case study.

• Journal of Magnetics
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• v.21 no.2
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• pp.204-208
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• 2016

This paper demonstrates the key parameter detection for smelting of submerged arc furnace (SAF) based on magnetic field radiation. A magnetic field radiation model for the inner structure of SAF is established based on relative theory of electromagnetic field. A simple equipment of 3D magnetic field detection system is developed by theoretical derivation and simulation. The experiments are carried out under the environment of industrial field and AC magnetic field generated by electrode currents and molten currents in the furnace is reflected outside of the furnace. The experimental results show that the key parameters of smelting including the position of electrode tip, the length of electric arc, and the liquid level of molten bath can be achieved. The computed tomography for SAF can be realized by the detection for smelting.

• Resources Recycling
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• v.22 no.1
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• pp.64-71
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• 2013

Mineral carbonation has been proposed as a possible way for $CO_2$ sequestration. The electric arc furnace slags consist of calcium, magnesium and aluminum silicates in various combinations. If they could be used instead of natural mineral silicates for carbonation, considerable energy savings and $CO_2$ emissions reductions could be achieved. Indirect aqueous carbonation of the slags consists of two steps, extraction of calcium and carbonation. Acetic acid leaching of electric arc furnace slags had been already studied to extract Ca in them, but it was reported that the carbonation of the extracted $Ca^{2+}$ in the leached solution would suffer from too slow kinetics, even at high pressure of $CO_2$. In this work, to develop more efficient extraction of the electric arc furnace slags, hydrochloric acid leaching to separate calcium from them was studied, and the results were compared with the acetic acid ones. The phase boundary between $Ca^{2+}$ and $CaCO_3$ in the solution with pH was determined by thermodynamic calculations. Hydrochloric acid was more effective than acetic acid for the extraction of Ca in electric arc furnace slag, and there is a possibility to recycle an unreacted hydrochloric acid in the leached solution by electrolysis or evaporation.

• Journal of the Korea Concrete Institute
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• v.25 no.1
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• pp.3-9
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• 2013

In ultra high strength concrete, when electric arc furnace oxidizing slag is substituted for sea sand as fine aggregate, compressive strength was improved about 15 MPa. To figure out the cause of the improvement in compressive strength, this study considered the dissolution characteristics of Ca component in fine aggregate and examined the microstructure, porosity, microhardness, and Ca/Si mole ratio on the interface of fine aggregate and paste. And to examine the mechanism of strength improvement resulted from the shape of fine aggregate, this study measured the surface roughness of fine aggregate with AFM. According to the result of this experiment, the mechanisms of strength improvement in ultra high strength concrete resulted from the use of electric arc furnace oxidizing slag as fine aggregate can be divided into chemical and physical mechanisms. In the chemical mechanism, the soluble Ca component contained in electric arc furnace oxidizing slag is dissolved and forms a hydrate between fine aggregate and paste to improve the interlocking strength of fine aggregate-paste. Also, it makes the microstructure around the fine aggregate. And in the physical mechanism, electric arc furnace oxidizing slag has a twice greater surface roughness than sea sand, so the interlocking strength between fine aggregate and paste increases, which contributes to the development of compressive strength.

• Resources Recycling
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• v.21 no.1
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• pp.30-40
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• 2012

Electric arc furnace slag is made in ironworks during steel refining, it is been increasing chemical and physical resistibility using ageing method of unstable state of melting steel slag for using concrete's fine aggregates. Which is been changing stable molecular structure of aggregates, it restrains moving of ion and molecule. In Korea, KS F 4571 has been prepared for using the electric arc furnace oxidizing slag to concrete aggregates(EFS). In this study, Electric arc furnace oxidizing slag is used in the PRCC(Polymer Rapid setting Cement Concrete) which is applied a bridge pavement of rehabilitation, largely. The results showed that the increment of compressive strength development by 10- 20%. The flexural strength of EFS-Con increased greatly as the electric arc furnace oxidizing slag changed. The compressive strength and flexural strength developed enough for opening the overlayed EFS-Con to the traffic after 4 hours of EFS-Con placement. The permeability of EFS-Con was evaluated as negligible due to its very low charge passed. Thus, EFS-Con could be used at repairing or overlaying the concrete at fast-track job sites.