Korean Chemical Engineering Research

The Korean Institute of Chemical Engineers (한국화학공학회)
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Characteristics and Risk Assessment of Flame Spreading Over Metal Dust Layers

퇴적금속 분진층을 전파하는 화염의 연소특성과 위험성 평가

  • 한우섭 ((주)TRC Korea 부설 위험관리연구소)
  • Received : 2004.09.07
  • Accepted : 2004.11.04
  • Published : 2005.02.28
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Abstract

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.

미립 금속분체에 대한 산업 수요 증가와 함께, 퇴적 금속분의 착화에 의한 화재, 폭발사고가 증가하고 있다. 본 연구에서는 퇴적 금속분체의 화재, 폭발 위험특성을 조사하기 위하여 새로운 실험장치를 개발하였다. 금속분(Mg, Zr, Ta, Ti) 및 PMMA(polymethyl methacrylate)분진을 사용하여, 연소 거동(소염거리, 화염전파속도) 및 화염전파에 미치는 $N_2$ 치환 분위기 농도의 영향 등을 실험적으로 상세히 조사하였다. 실험결과로부터, 퇴적 금속 분체의 화염전파속도는 PMMA보다 크고, 화염전파속도의 퇴적층 두께에 대한 의존성은 작으며, 질소 치환 분위기에서의 Mg의 한계 산소 농도는 3.6-3.7 vol%로 나타났다. 퇴적금속 분체층의 화염전파속도와 소염거리 역수는 높은 상관관계를 가지고 있으며, 이들 연소성 지표에 있어서 상대적인 위험성의 예측이 가능하다.

Keywords

References

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