• Proceedings of the Korean Institute of Industrial Safety Conference
• /
• 2004.10a
• /
• pp.397-402
• /
• 2004

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
• /
• 2013.04a
• /
• pp.115-115
• /
• 2013

최근의 분진폭발은 플라스틱, 의약품, 목재, 곡물 저장고, 고체연료, 화학제품 제조공정 등을 포함하여 성형 및 가공 공정 등에서 화재폭발사고가 발생되고 있다. 폐목재를 재활용하여 PB(Particle board)를 생산하는 국내 제조사업장에서는 화재폭발 사고가 빈번히 발생하고 있어 예방대책이 요구되고 있다. 본 연구에서는 폐목재 제조공정의 사고예방과 목재분진 취급공정에 대한 안전대책 등을 제시하기 위하여 사고원인 물질인 폐목재 부유분진의 폭발특성실험을 실시하고 실험결과를 검토하였다. 또한 폐목재 분진의 화재폭발위험성을 상세히 평가하기 위하여 해당 물질의 자연발화점, 축열저장시험, 및 최소점화에너지 등의 화재폭발위험특성값을 실험적으로 조사하였다. 본 연구에서 사용한 폐목재 시료의 비구형 입자형태를 가지는데 입도분석기의 측정 결과 평균 입경은 $15.96{\mu}m$로 조사되었다. 또한 목재 분진의 함수율은 3.88%이며 중금속함유량은 1.73%이다. 자연발화점 측정결과 $225.5^{\circ}C$로서 비교적 낮게 측정되었고 퇴적분진에 대한 화재의 위험성은 높게 나타났다. 반면에 축열저장시험 결과를 통하여 공정관리 온도 및 보관온도를 $150^{\circ}C$ 이하로 관리하면 축열에 의한 자기분해 위험성은 낮은 것으로 판단되었다. 그러므로 축열에 의한 화재폭발 등의 위험성은 낮은 것으로 사료 된다. 최대폭발압력($P_{max}$)은 8.7 bar이며 폭발하한농도 (LEL)는 $60g/m^3$으로 나타났다. 부유분진의 폭발특성실험 결과 분진폭발지수(Kst)는 폭발등급 St 1 (0$bar{\cdot}m/s$)으로 나타났으며 폭발에 의한 위험성이 약한 분진으로 판정되었다. 최소점화에너지(MIE)는 10mJ < MIE <30mJ의 범위로 측정되었으며, 계산에 의해 추정된 최소점화 에너지(Es) 값은 14 mJ로서 일반적인 발화감도(Normal ignition sensitive)로 분류되었다. 이는 실질적인 점화원만 제거하여도 분진폭발을 예방할 수 있다는 것을 의미한다. 그러나 분진 폭발사고를 예방을 위하여 MIE값이 공정운전온도 $100^{\circ}C$ 초과 시에 급격히 낮아질 수 있으므로 운전 온도 설정에 있어서 주의가 필요하다.

• Fire Science and Engineering
• /
• v.13 no.2
• /
• pp.26-32
• /
• 1999

We had investigated combustion pro야$\pi$ies of rice bran dusts. Decomposition of rice bran d dusts with temperature were investigated using DSC and the weight loss according to t temperature using TGA in order to find the thermal hazard of rice bran dusts, and the p properties of dust explosion in variation of their dust with the same particle size. Using H Hartman's dust explosion apparatus which estimate dust explosion by electric ignition after m making dust disperse by compressed air, dust explosion experiments have been conducted by v varying concen$\sigma$ation and size of rice br뻐 dust. According to the results for thermodynamic stability of rice bran dust, there are little change of initiation temperature of heat generation 때d heating value for used particle size. But i initiation temperature of heat generation decreased with high heating rate whereas d decomposition heat increased with particle size. Also, the explosion pressure was increased as t the ignition energy increased and average maximum explosion pressure was 13.5 kgv'cnt for 5 BJ/60 mesh and 1.5 뼈Ie미 dust concentration.

• Journal of the Society of Disaster Information
• /
• v.14 no.1
• /
• pp.89-100
• /
• 2018

when the explosive wastes to be treated as designated wastes are brought into the wastes treatment plant by mistake and lead to an explosion in the wastes disposal process, many people and property damage are involved. Waste should be treated properly. As mentioned in this paper, ignition reac- tion tests of ignitable re-burning of explosives packing material waste (solid butadiene) confirmed that ignition was easily occurred, and that even small ignition sources were easily ignited and burned quickly and explosively. In particular, when explosives are loaded into incineration wastes in large quantities and mixed with organic compound wastes, such as fire and explosion accidents caused by explosives packing materials at waste disposal sites, flammable and oxidative gases are generated due to mutual oxidation and pyrolysis It is confirmed that there is a possibility that ignition sources such as spark ignite and instantaneously lead to explosion. It is hoped that this study will be a small reference for on - site detection in the field of fire, and it is expected that the fire - fighting agency will be recognized as a fire investigation agency and will contribute to the improvement of the credibility.

• Analytical Science and Technology
• /
• v.22 no.4
• /
• pp.285-292
• /
• 2009

It has been observed that, after long term storage, some ammunitions are misfired by tamping (combustionstopping) due to aging of the chemicals loaded in the ammunitions. Used in ammunitions are percussion powder which provides the initial energy, igniter which ignites the percussion powder, and a delay system that delays the combustion for a period of time. The percussion powder is loaded first, followed by the igniter and then the delay system, and the ammunitions explode by the energy being transferred in the same order. Tamping occurs by combustion-stopping of the igniter or insufficient energy transfer from the igniter to the delay system or the combustion-stopping of the delay system, which are suspected to be caused by low purity of the components, inappropriate mixing ratio, size distribution of particulate components, type of the binder, blending method, hydrolysis by the humidity penetrated during the long term storage, and chemical changes of the components by high temperature. Goal of this study is to find the causes of the combustion-stopping of the igniter and the delay system of the ammunitions after long term storage. In this study, a method was developed for testing of the combustion-stopping, and the size distributions of the particulate components were analyzed with field-flow fractionation (FFF), and then the mechanism of chemical change during long term storage was investigated by thermal analysis (differential scanning calorimetry), XRD (X-ray diffractometry), and XPS (X-ray photoelectron spectroscopy). For the ignition system, M (metal)-O (oxygen) and M-OH peaks were observed at the oxygen's 1s position in the XPS spectrum. It was also found by XRD that $Fe_3O_4$ was produced. Thus it can be concluded that the combustion-stopping is caused by reduction in energy due to oxidation of the igniter.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2008.05a
• /
• pp.53-56
• /
• 2008

When someone measuring for pressure of a Solid Rocket Motor(SRM) at Static Firing Test, generally, used with pressure tube to be filled in Oil. But, if you used pressure tube with oil, you were worried about possibility of spilled oil when you measured pressure in SRM at high altitude environment. Because it usually connected at ignitor. In this paper, We described how to make a pressure tube without oil and matters to be attended to design it.

• Journal of the Korean Institute of Gas
• /
• v.17 no.2
• /
• pp.44-49
• /
• 2013

Due to rapid rise of consuming rate for natural gas, installation and operation of high pressure natural gas pipeline is inevitable for high rate of gas transportation. Accordingly incidents on the underground high pressure natural gas pipeline come from various reasons will lead to massive release of natural gas and gas dispersion in the air. Further, fire and explosion from ignition of released gas may cause large damage. This study is for release rate, dispersion and flash fire of natural gas to establish a safety management system, setting emergency plan and safety distance.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
• /
• 2011.11a
• /
• pp.466-469
• /
• 2011

Acrylic Polymer는 충격보강재 및 가공조제 등의 용도로 다양한 산업현장에서 사용되어지고 있는데, 본 제품 제조회사에서 고객사로 제품 납품 후 원료 투입 중 분진폭발이 발생하여 본 위험성평가를 의뢰하였다. 분진의 위험 특성에 대한 분석은 일반적으로 퇴적분진(Dust Layers)와 부유분진(Dust Clouds)으로 구별되어진다. 본 연구에서는 스위스 Kuhner사에서 제작된 분진폭발장치를 이용하여 아크릴 부유분진의 화재.폭발위험성에 대하여 고찰하였다. Acrylic Polymer 부유분진의 폭발위험성은 최대폭발압력 약 6bar, 최대폭발압력상승속도 67 bar/s, Kst 값은 $18m{\cdot}bar/s$로 폭발등급으로 구분하면 St1 [0$bar{\cdot}m/s$]으로 분류되어 "폭발에 의한 위험성이 낮은 분진"에 속하며, 최소점화에너지(MIE)는 300 mJ < MIE < 1,000 mJ로 Normal Sensitivity로서 정전기와 같은 점화원 제거만으로도 어느 정도 충분히 폭발 등을 방지 할 수 있을 것으로 판단된다.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2017.05a
• /
• pp.734-738
• /
• 2017

In the present study, dominant factors for temperature increase and effects of mass entering the resonance tube of the gas-dynamic igniter are investigated. Using RhoCentralFoam solver in OpenFOAM program, numerical simulation is performed for three different cases. In the results, the heating of the working fluid is found to be a result from aero-thermodynamic phenomena. Appropriate mass entering to the resonance tube is found to be an important dominant factor as well.

• Journal of Hydrogen and New Energy
• /
• v.35 no.4
• /
• pp.415-427
• /
• 2024

Explosion experiments were conducted using a rectangular concrete structure filled with hydrogen-air mixture (29.0%). In addition, the effect of ignition location on explosion was investigated. The impact on overpressure and flame was increased with the increasing distance of the ignition source from the vent. Importantly, depending on the ignition location the incident pressure was up to 24.4 times higher, while the reflected pressure was 8.7 times higher. Additionally, a maximum external overpressure of 30.01 kPa was measured at a distance of 2.4 m from the vent, predicting damage to humans at the injury level (1% fatality probability). Whereas, no significant damage would occur at a distance of 7.4 m or more from the vent.