• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2003년도 추계학술대회 논문집 전력기술부문
• /
• pp.17-19
• /
• 2003

Electric arc furnace has consumed plenty of power. Hence electric arc furnace can be expected to use for demand side management. When electric arc furnace use for demand side management, electric arc furnace frequently occur a starting and a stop. Electric arc furnace irregularity change consumption of power. Due to character of time-varing and non-linear, electirc arc furnace has a problem with voltage quality(flicker, harmonics). Producted harmonic in electric art furnace is different any harmonic source because of electric arc furnace peculiar operating. Accordingly, analysis for generated harmonic in electric arc furnace operating is demanded. This paper analyze effect of harmonic by arc furnace operating.

• 한국세라믹학회지
• /
• 제43권7호
• /
• pp.408-414
• /
• 2006

Properties of slag cement that contained 50 wt% of blast furnace slag were studied when replaced blast furnace slag powder with electric arc furnace slag powder. Electric arc furnace slag was aged for about 2 months in the air by being crushed to be 1-3 mm in size. As a result of the experiment, it was proven that the water content for obtaining the same consistency became decreased as slag is replaced with electric arc furnace slag instead of blast furnace slag. Also, the workability of mortar increased about 30% at the same ratio of water to binder when blast furnace slag was completely replaced with electric arc furnace slag. The compressive strength of mortar on the 28 days increased when a slag replacement rate became 10 wt%, however, it rather decreased when the slag replacement rate exceeded 10 wt%. The heat of hydration became higher for the first 14 h in case of the replacement of slag cement by electric arc furnace slag. Yet, it decreased when 14 h had passed. Therefore, when all blast furnace slag was replaced with electric arc furnace slag, about 15 cal/g heat of hydration decreased when it passed about 72 h.

• Journal of Advanced Marine Engineering and Technology
• /
• 제21권3호
• /
• pp.311-318
• /
• 1997

In this paper, a controller with monitoring functions is proposed for controlling temperature of an electric furnace system. The controller includes holding and ramp control functions, and the control program for the temperature process monitor of the electric furnace. For this purpose, the implementation and performance of auto tuning algorithms in a computer¬based controller is studied in relation to control of a nonlinear electric furnace system which is characterized with large time delay. The communicator of a control and detection signals, between the controller and the electric furnace is implemented by an I/O data card. Experiments for the practical electric furnace are performed to illustrate the performance of the proposed controller.

• 한국건축시공학회:학술대회논문집
• /
• 한국건축시공학회 2011년도 추계 학술논문 발표대회
• /
• pp.243-244
• /
• 2011

In general, magnetite or barite (density: more than 4.0ton/㎥) has been used in concrete for radiation shielding, and radiation tests have been performed to evaluate shielding performance. However, researchers have not studied concrete for radiation shielding that utilizes electric arc furnace oxidizing slag. This research aims to utilize electric arc furnace oxidizing slag which depends on reclamation as environment-friendly concrete materials by using coarse and fine aggregates of electric arc furnace slag containing 30% ferrous metal and with a density of around 3.0~3.8 ton/㎥. Accordingly, this research has judged that the high density electric arc furnace oxidizing slag aggregate can be applied to radiation shielding concrete. It has also examined the possibility of developing radiation shielding concrete utilizing electric arc furnace oxidizing slag aggregate by comparing concrete utilizing all fine and coarse aggregate of electric arc furnace oxidizing slag with concrete using magnetite.

• 한국건축시공학회:학술대회논문집
• /
• 한국건축시공학회 2013년도 춘계 학술논문 발표대회
• /
• pp.35-36
• /
• 2013

Electric arc furnace oxidizing slag from massively produced steel slag has been used in road bases and subbases, hot mix asphalt, and landfill. Electric arc furnace oxidizing slag contains iron (15%~30%) and has a high density of 3.0~3.7 ton/m3. Depending on the type and amount of concrete aggregates, the radiation-shielding characteristics can vary. Therefore, aggregates of electric arc furnace oxidizing slag can be considered for the production of radiation-shielding concrete. The experimental design of this study is experiments on Compressive strength experiments, X-ray irradiation experiments, and experiments related to the unit volume weight were carried out on hardened concrete. This experiment compared the performance evaluation of radiation shielding of concrete using electric arc furnace oxidizing slag.

• 한국안전학회지
• /
• 제12권2호
• /
• pp.80-86
• /
• 1997

In this paper, a temperature controller with monitor function is proposed for the electric furnace system. This controller includes holding and ramp control function, and the control program for the temperature process monitor of the electric furnace. For this purpose, the implementation and performance of auto tuning algorithms in a computer-based controller was studied in relation to the control of nonlinear electric furnace system which is characterized with large delay time. The control program for this controller programmed by c-language. To communicate a control and detection signals, between the controller and the electric furnace is implemented by the I/O data card. We apply the temperature controller to the practical electric furnace. As a result, the proposed controller shows the better status characteristic.

• 제어로봇시스템학회논문지
• /
• 제2권1호
• /
• pp.60-66
• /
• 1996

Model Based Predictive Control(MBPC) has been widely used in predictive control since 80's. GPC[1] which is the superset of many MBPC strategies a popular method, but GPC has some weakness, such as insufficient stability analysis, non-applicability to internally unstable systems. However, CRHPC[2] proposed in 1991 overcomes the above limitations. So we chose RHPC based on CRHPC for electric furnace control. An electric furnace which has nonlinear properties and large time delay is difficult to control by linear controller because it needs nearly perfect modelling and optimal gain in case of PID. As a result, those controls are very time-consuming. In this paper, we applied RHPC with equality constraint to electric furnace. The reults of experiments also include the case of RHPC with monotonic weighting improving the transient response and including unmodelled dynamics. So, This paper proved the practical aspect of RHPC for real processes.

• 한국정보통신학회:학술대회논문집
• /
• 한국정보통신학회 2013년도 춘계학술대회
• /
• pp.904-907
• /
• 2013

최대전력관리장치는 사용 전력량이 목표 전력량을 초과하는 것으로 예측되면 연결된 부하장치를 차단하여 사용 전력량이 목표 전력량을 초과하지 않도록 제어하는 장치이다. 이러한 ON/OFF 방식을 전기로의 전력 관리에 적용하면 전력을 공급하는 인버터와 전기히터의 기동 및 정지동작이 반복적으로 수행되게 된다. 이는 인버터와 전기히터에 전기적 손상을 가중시켜 수명을 단축시킬 수 있다는 문제점이 있다. 또한 전력 관리에 의해 전력 공급이 차단되었을 때 복귀 시점까지 온도를 조절할 수 없다는 단점이 있다. 본 논문에서는 목표 전력량을 초과하지 않는 범위 내에서 지속적인 전력의 인가를 통해 인버터와 전기히터의 전기적 손상을 방지하고 전기로로 인가되는 전력량을 유기적으로 자동 조절하기 위해 전기로 원격 제어기를 사용한 전력관리 시스템을 개발한다.

• 열처리공학회지
• /
• 제36권1호
• /
• pp.22-32
• /
• 2023

In general, when scrap is dissolved in an electric arc furnace, the amount of electric furnace steel dust (EAFD) generated is about 1.5% of the scrap charge amount, and the electric furnace steel dust collected by the bag filter is charged into the Rotary Kiln or Rotary Hearth Furnace (RHF), and the zinc component is recovered as crude zinc oxide, at which time a clinker of Fe-Base is generated. In this research, first, for the efficient resource conversion of electric furnace steel dust, a reduction and roasting experiment was conducted and the reaction kinetics was examined. As a result of the experiment, it was observed that the reduction and roasting reaction was actively conducted in the range of 1100~1150℃, and melting occurred in the range of 1250℃. In the past, this clinker was widely used as a roadbed material for road construction and an Fe-Source for cement production, but in recent years, it has been mainly reclaimed due to strengthening environmental standards. However, landfill treatment is by no means a desirable treatment method due to environmental pollution caused by leachate, expensive landfill costs, and waste of Fe resources. Therefore, in order to more actively recycle the Fe component in the clinker, first of all the clinker was pulverized into an optimal particle size, and anthracite and binder (starch) were added to the magnetic material obtained by specific gravity and magnetic separation for briquet. As a experimental results, it was possible to efficiently separate clinker as Fe component and other slag component by specific gravity and magnetic force. As a results of loading and dissolving the manufactured briquet clinker in an electric arc furnace, it was observed that the unit of power and production yield were clearly improved and the carbon addition effect in molten metal was also somewhat.

• 콘크리트학회논문집
• /
• 제14권4호
• /
• pp.597-607
• /
• 2002

우리나라에서 2000년도에 발생된 전기로 및 전로슬래그를 합하면 약 600만 톤 정도로서 주로 도로포장재료 및 매립재 등과 같은 한정된 용도로만 활용되어 왔다. 그 이유는 제강과정 중 유리석회가 슬래그화 되지 않고 불안정한 상태로 슬래그 내부에 잔존하기 때문에 콘크리트 구조물 내에서 팽창을 일으킬 가능성이 클 뿐만 아니라, 팽창이 심할 경우 구조물의 균열 내지는 붕괴까지도 야기 시킬 수 있으므로 콘크리트용 골재로 사용해서는 안 된다고 규정하고 있다. 따라서 제강슬래그를 콘크리트용 골재로 사용하기 위해서는 제강슬래그 자체의 팽창성 억제 내지는 안정화 처리가 우선 해결되어야 할 과제로 생각된다. 본 연구에서는 제강슬래그 골재의 팽창성을 저감시키기 위한 목적으로 6종류의 에이징 방법을 선정하여 안정화의 효율에 대하여 비교 검토하였다. 전로슬래그 골재의 경우, 본 연구에서 실시한 에이징 처리 방법으로서는 콘크리트용 골재로서 요구되는 팽창률을 저감시키는데 한계가 있었을 뿐만 아니라, 에이징 처리한 전로슬래그 골재 사용 콘크리트의 강도도 재령과 더불어 감소하는 문제점이 있음을 확인하였다. 그러나 전기로슬래그 골재를 온수중 및 증기중 에이징 처리할 경우, 팽창률이 전로슬래그 골재의 약 2/3 정도에 지나지 않는 효율을 나타내었으며, 이를 사용한 콘크리트의 강도도 전로슬래그 골재 사용 콘크리트와는 달리 보통콘크리트의 강도에 상응하는 비교적 좋은 결과를 나타내므로 콘크리트용 골재로서 사용 가능성을 시사하였다.