• Clean Technology
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• v.5 no.1
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• pp.30-41
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• 1999

The experimental set-up with a 1m long ceramic candle filter of Schumacher(Germany) was built in this work. The dust velocity field around the filter was measured using PDPA. The effects of dust cake layer and dust inlet position on the dust velocity field were also analyzed. It was found that the filtration velocity decreases as the dust cake builds up on the filter. The filtration velocity largely decreases around the filters near the dust inlet since the dust cake develops fast there. The average dust velocity on the filter due to the pressure difference through the filter was measured to be 0.28m/s. More uniform dust velocity field around the filter was obtained when feeding dust in a lower position of the pressure vessel.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.05b
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• pp.405-406
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• 2003

분진여과시 형성되는 분진 케이크는 궁극적인 여과 성능을 좌우하며, 필터의 구조, 분진 입자의 형태나 크기, 분진농도, 여과속도 등에 의해 영향을 받는다 특히 필터의 표면 구조나 기공 크기는 여과 초기 단계의 케이크 층의 구조를 결정하며, 연속적인 여과시 초기 케이크 층은 다음에 쌓이는 케이크 형성과 비저항에 영향을 주므로 필터 medium 구조 또한 분진여과 과정에서 중요한 영향 요인이 된다. 본 연구에서는 필터 medium의 구조가 서로 다른 고온가스정화용 복합 세라믹 필터, metal fiber mat, 스테인레스 필터를 이용하여 분진농도와 여과속도를 변수로 하여 분진 여과 실험을 함으로써 각각의 필터에 대한 케이크 비저항과 기공율을 실험과 이론식으로부터 추정하였다. (중략)

• 한국신재생에너지학회:학술대회논문집
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• 2008.10a
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• pp.246-249
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• 2008

IGCC (석탄가스화 복합발전) 시스템 공정 중 가스화기에서 발생되는 합성가스 내에는 높은 농도의 분진들이 함유되어 있기 때문에 하부 공정들을 보호하기 위해서는 가스화기 후단에 집진장치가 필히 설치되어야 한다. 집진장치의 설계 제작 운전에 있어서 점착성 분진층 부착,분진 브리징, 필터 파손 현상 등과 같은 다양한 문제점들로 인하여 고온의 합성가스를 처리하는 데는 아직 기술적 한계들이 산재해 있는 상황이다. 이와 같은 문제점들은 필터에 부착된 분진층의 탈진성능을 향상시키거나, 필터의 열피로를 줄일 수 있도록 필터 재생을 위한 탈진의 횟수를 줄이는 방법을 통하여 해결될 수 있다. 본 연구에서는 파일롯 규모의 IGCC용 세라믹캔들필터 집진장치에서의 가스 유입 및 탈진 조건에 따른 집진장치의 차압 특성 변화를 수치해석과 실험을 통하여 분석함으로써 탈진성능을 향상시킬 수 있는 조건과 탈진 횟수를 최소화시킬 수 있는 방안을 도출하고자 하였다.

• Journal of the Korean Institute of Gas
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• v.1 no.1
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• pp.113-119
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• 1997

The detection capability of UV flame detector in dust environment would be impaired. In this study, an experiment was conducted, in an effort to further understand the behavior of UV flame detector and to evaluate its detection capability in industry dust environment. Detergent powder, coal powder and dry extinguishing agent were selected as dust sources. Flaming sources include propane and gasoline flame. Experiment results indicate that dust can cause remarkable attenuation of UV flame radiation. The concentration of dust and the length of air layer where dust dispersed determine the reduction of radiation intensity. On the other hand, the attenuation of UV radiation also depends on the chemical and Physical properties of dust.

• Korean Chemical Engineering Research
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• v.60 no.2
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• pp.229-236
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• 2022

An experimental investigation was conducted on the influences of median size, dust concentration, dust condition (cloud and layer) for the fire and explosion hazard assessment of dusts with the same powder property. For this purpose, tests have been performed in accordance with 20 L explosion sphere, thermogravi- metric analyze, combustion rate tester (UN method). We investigated the explosion characteristics and flame propagation velocity (FPV) in dust cloud and the flame spread velocity(FSV) over dust layer on 8 dust samples with different particle sizes of 4 types of dusts (Sugar, Mg, Al, Zr). An explosion hazard increased with decreasing particle size in Mg and Al dust clouds, but sugar did not show the effect of explosion hazard due to particle size change in dust clouds. The flame propagation velocity (FPV) of suspended dusts increased significantly when the particle size decreased from micro to nano than the variation of particle size in micro range. The flame spread velocity (FSV) over dust layer showed a tendency to increase over the inclined dust layers (30° slope) rather than the horizontal dust layers (0° slope). The flame spread rate (FSV) over dust layers increased on the inclined dust layer (30° slope) rather than the horizontal dust layer (0° slope) and was higher upward flame than the downward flame in condition of inclined dust layers(30° slope).

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2007.11a
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• pp.143-144
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• 2007

• Korean Chemical Engineering Research
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• v.43 no.1
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• pp.47-52
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• 2005

The wide use of metal dusts have been found in industrial field and many dust explosion accidents occur by fire spread of dust layer. In this study, we developed a new experimental device to examine fire and explosion characteristics of the dust layer. Aspects of the burning zone over metals(Mg, Zr, Ta, Ti, etc) and PMMA(Polymethyl methacrylate) dust layers have been investigated experimentally to clarify behaviors (Spread rate and quenching distance) and effects of $N_2$ surrounding gas on the fire spread over metal dust layers. From the experimental result, it was found that the spread rate of metal dusts is larger than PMMA, the dependability of spread rate over the thickness of dust layer is small, and the minimum oxygen concentration of spread flame over Mg dust layer is 3.6-3.7 vol%. Since high correlation between the spread rate and the reciprocal of quenching distance was seen, relative risk prediction in those inflammable parameters can be predicted.

• Journal of the Korean Ceramic Society
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• v.40 no.9
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• pp.891-896
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• 2003

Novel fabrication technique was developed for high strength Reaction-Bonded SiC (RBSC) hot gas filter for use in IGCC (Integrated Gasification Combined Cycle) system. The room and high temperature fracture strengths for Si-melt infiltrated reaction-bonded SiC were 50-123, and 60-66 MPa, respectively. The average pore size was 60-70 $\mu\textrm{m}$ and the porosity was about 34 vol％. RBSC infiltrated with molten silicon showed improved fracture strength at high temperature, as compared to that of clay-bonded SiC, due to SiC/Si phase present within SiC phase. The thickness for SiC/Si phase was increased with increasing powder particle size of SiC from 10 to 34 $\mu\textrm{m}$. Pressure drop with dust particles showed similar response as compared to that for Schumacher type 20 filter. The filter fabricated in the present study showed good performance in that the filtered powder size was reduced drastically to below 1 $\mu\textrm{m}$ within 4 min.

• Explosives and Blasting
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• v.36 no.4
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• pp.48-61
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• 2018

This case study is concerned with the project of the explosive demolition for the KOGAS office building located in Bundang district in Seongnam city. Since the office building was a kind of long-span beam structures, a mechanical demolition method using jacking support systems was considered in the beginning of the project. With consideration of the excessive reinforcement cost, uncertainty of safety, and prolonged construction period, however, the original plan was later changed to use an explosive demolition method. For the purpose of protecting nearby buildings and facilities during the collapse process, the explosive initiation sequence was elaborately designed to bring down the building structure towards its front left corner. A total of over 550 electronic detonators (Unitronic 600) was used to sequentially initiate the explosives installed at appropriate columns in the first, second, and fifth floors. To diminish dust production, water bags of small and large sizes were respectively installed at each column and on the floors to be blasted. As such, every effort was exercised to mitigate overall noise, dust, and shock vibrations that could be generated during the explosive demolition process for the office building.

• Journal of Korean Society for Atmospheric Environment
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• v.20 no.3
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• pp.371-380
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• 2004

In the dust separation by using porous filter media, the structure of dust layer deposited on the filter surface of filter medium directly affects the effective filtration. The present study has investigated the specific resistance (K$_2$') of the dust layer and its porosity ($\varepsilon$$_{c}$) for three different filters; FA composite filter, metal fiber filter and stainless filter. The specific resistance (K$_2$') increased and at the same time the cake porosity ($\varepsilon$$_{c}$) decreased with the increase of filtration velocity, possibly due to the compressible effect of dust layer. However, under the low dust concentration, subsequent dust particles would block the open channels through the layer resulting in high specific resistance of the layer. The FA composite filter among three filters was shown to be the most effective filter for dust cake filtration at low filtration velocities less than 0.1 m/s for an approximate dust concentration of 5 g/㎥.