• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
• /
• 2007.11a
• /
• pp.235-237
• /
• 2007

본 연구는 현장 분진포집에 의한 도전율측정과 전기설비 위험을 평가한 것이다. 현장에서의 분진발생은 전기설비에 악영향을 주어 전기설비의 운영시 발생되는 것과 주변환경적 요인에 의해 발생되는 분진이 주를 이루고 있다. 현장에서 포집된 분진으로부터 분진의 종류, 도전율 특성에 의해 전기설비가 영향을 미칠 것으로 판단되었다. 또한 일부 부식성 가스에 의해 노출된 전기설비의 위험성을 분석하고 관리기준을 마련할 필요가 있는 것으로 나타났다. 분진의 종류에 따라 사고의 과정은 빠르거나 오랫동안 지속되었다가 발생되는 근원적 원인을 규명하고자 국내현장에서 분포되고 있는 분진의 종류와 특성 분석과 관련규정을 검토하고 현장실태에서 나타난 문제점을 검토하여 분진발생지역에서의 전기설비 안전관리를 위한 기준마련에 이용될 것으로 기대된다.

• Resources Recycling
• /
• v.26 no.5
• /
• pp.48-53
• /
• 2017

During steelmaking on EAF, 1 ~ 2% of dust is generated. EAF Dust contains 20 ~ 30% of Zn and Fe. Dust contained in Off-gas is passed through combustion tower and cooling tower, and then captured in bag filter. About 15 wt.% of dust is dropped at the bottom of Combustion tower by its specific gravity, which was also carried out to recycle company with more higher charge than Bag filter dust. This study is focused on the combustion tower dust, and seperation as a function of operation period and particle size. As a result, Zn and Fe content of dust is more affected by size factor than operation period.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.22 no.9
• /
• pp.103-110
• /
• 2008

In terms of electrical safety, environmental impact assessment and revision of domestic regulation are needed for the electric facilities. In this paper, risk of electric facilities is assessed by the spot measures and analysis in dust generation area. Adhesion dust in a surface of insulated materials cause electrical accidents. In a mechanism of these accidents, when the dust lie on electric facilities, a leakage current is flowed and the surface of insulated material is carbonized. Hereafter, electrical fire is generated due to Joule's heat. As the results, dusts are found in protection devices or panel board and sampled dusts vary in sampled amounts and conductivity severally. For the most part, sodium is detected but zinc and calcium are detected in case of reclaimed rubber factory by the ICP-AES(Inductively Coupled Plasma-Atomic Emission Spectroscopy). In a sewerage, the ingredients such as sodium, magnesium, iron, calcium, aluminium, etc are detected uniformly. So that, results of the spot measures and analysis of dusts are become the important data for the assessment of electrical hazard in dust generation area.

• Resources Recycling
• /
• v.23 no.1
• /
• pp.80-85
• /
• 2014

Commercially operating EAF dust recycling processes were investigated by means of unit process analysis. Over 80 % of EAF recycling processes are Waelz kiln process adapted a rotary kiln as a main reactor. There are differences among these pyrometallurgical processes by plant location and timely important things such as environmental regulations. In this paper, the characteristics of each plants are analysed with the point of unit process.

• Proceedings of the Korea Air Pollution Research Association Conference
• /
• 2000.11a
• /
• pp.270-272
• /
• 2000

석탄 화력 발전소 둥에서 배출되는 입자상의 분진은 대부분 고 비저항 분진이며, 분진의 전기저항치가 $10^{12}$ $\Omega$-cm 이상의 초고전기저항 분진에 대하여 역코로나 방지대책으로 S $O_3$ 주입기술이 있는데, 기존의 화학적인 주입설비는 매우 고가이다. 이에 본 연구에서는 배가스중의 S $O_2$ 가스를 전기 코로나 플라즈마에 의하여 S $O_3$로 변환시켜 궁극적으로 고 전기저항 분진의 전기저항을 저하시켜 고집진 효율을 달성하고자 하는 시스템에서 이에 대한 타당성을 검증하기 위하여 실험실 규모의 기초실험을 수행하였다(H. Szwed and St. Bach, 1996). (중략)

• Resources Recycling
• /
• v.27 no.2
• /
• pp.68-76
• /
• 2018

EAF (Electric arc furnace) dust is an important secondary resource such as zinc, lead, and iron. Recycling of EAF dust is benefit to solving disposal and environmental problems caused by the heavy metals entrained in the dust. In this study, pyrometallurgical treatment technology of EAF dust reviewed for the improvement of conventional process and development of new process. The existing technologies categorized into four groups: those by rotary kiln process, rotary hearth furnace (RHF) process, shaft type process, and reduction smelting process. The product of these processes are ZnO and Fe or slag as a waste. Their mechanisms for the production of ZnO from EAF dust were carbothermic reduction and oxidation of zinc gas with air.

• Resources Recycling
• /
• v.13 no.2
• /
• pp.39-46
• /
• 2004

The amount of electric furnace dust has been steadily increasing due to the increase of iron scraps which are usually recycled by electric furnace melting process. To date, this electric furnace dust has usually been treated by landfilling, however, because of shortage of landfill sites and heavy metal leaching more desirable treatment schemes are urgently needed. Among several possible schemes for the proper treatment of electric furnace dust, its recycling can be said to be most desirable. In present study, the triboelectrostatic separation of zinc and zinc-containing components from electric furnace dust was attempted based on its physicochemical properties such as particle shape, size distribution, and chemical assay. The dust was found to be mixed with spherical and non-spherical shaped particles and its major component materials were $ZnFe_2$$O_4$, ZnO, Fe, Zn, and FeO. The content of zinc-containing components in the entire dust was observed to be in the range of 15～30 wt%, which reasonably justified that zinc is recyclable. The triboelectrostatic characteristic of each component material was found to be different each other since their work functions were different, and based on this characteristic zinc and zinc-containing component could be flirty separated from the dust. After selecting a proper tribo-elec-trification material, the separation features of zinc and zinc-containing component were examined by taking the distance of electrodes, electric field strength, and scavenging as the experimental variables. The highest zinc-content obtained under the optimal separating condition was found to be up to 50wt%.

• Resources Recycling
• /
• v.12 no.6
• /
• pp.47-56
• /
• 2003

PVC(polyvinyl chloride) powder were mixed with EAF(Electric Arc Furnace) dust and made as pellets. In order to recover the hydrochloride emitted from pyrolysis of PVC and the valuable metals in dust through making chlorides, pellets were roasted at $300 ^{\circ}C$ and investigated about the generation of chlorides. Two dust samples were collected at I steel making Co. and P Co. (called I dust and P dust respectively), which were mainly composed of zincite and franklinite. It was confirmed that about 50% of Zn in I dust and 48% of Zn in P dust compose zincite. The emission of HCl gas was completed in 15 min at 30$0^{\circ}C$ and the HCl mostly reacted with dust and made chlorides under 20% PVC mixed ratio. Because the reaction of HCl with zincite was faster than with franklinit, when generation and volatilization of ferric chloride is not allowed, the equivalent PVC powder mixed ratio in pellet depended on the amount of zincite in dust.

• Resources Recycling
• /
• v.11 no.4
• /
• pp.37-43
• /
• 2002

As the consumption of galvanized steels in cans and automobiles and the quantity of scraps increase, the recycling problems of EAF dust become a important problem. Valuable metals such as Fe, Zn, Pb are of continued interest to metallurgists. To recover the valuable metal and to remove the toxicity of EAF dust, high temperature smelting process is or researching as a pilot scale. The Reduction kinetics of Zn in EAF dust is so important in a view of the economic consideration of the process. In this study, the kinetics behavior of Zn in EAF dust were measured as a point of application in high temperature smelting process. The rate control step in ZnO and franklinite is revealed to be chemical reaction on the reaction surface.

• Resources Recycling
• /
• v.12 no.5
• /
• pp.50-56
• /
• 2003

To be recycled iron and heat source in EAF, EAF dust and mill scale generated from steelmaking plant should be made to iron carbide. Behavior of reduction and carburization in EAF dust and mill scale is studied to get fundamental data. EAF dust and mill scale are carburized at $650^{\circ}C$ by 100% CO gas. The carbon content of iron carbide(about 9 wt,% C) is higher than that of cementite without free carbon. The 1.2 times of calculated carbon content is suitable for reduction of EAF dust. The reduction temperature is appropriate to $900^{\circ}C$ in EAF dust and $1000^{\circ}C$ in mill scale. The carburization rate of mill scale are faster than those of EAF dust. The composition of super iron carbide is almost $Fe_2$C.