• 한국안전학회지
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• 제24권5호
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• pp.13-20
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• 2009

The risk assessment of thermal hazard to identify chemical or process hazard during early process developments have been considered. The early identification of thermal hazards associated with a process, such as rapid heats of reaction, exothermic decompositions, and the potential for thermal runaways before any large scale operations are undertaken. This paper presents to evaluate the safe operating parameters/envelope for exist plant operations. The assessment of thermal hazard with operating conditions such as amount of process materials, inhibitor, and catalyst on esterification process in manufacture of concrete mixture agents are described. The experiments were performed by a sort of calorimetry with the Multimax reactor system as a screening tool. The aim of the study was to evaluate the thermal risk of process material and mixture in terms of safety security to be practical applications in esterification process. It suggested that we should provide the thermal hazard of reaction materials to present safe operating conditions with cause of accident through this study.

• 한국안전학회지
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• 제24권4호
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• pp.40-46
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• 2009

The early identification of thermal hazards associated with a process such as the heats of reaction, exothermic decompositions, and the understanding of thermodynamics before any large scale operations are undertaken. The evaluation of reaction factors and thermal behavior on esterification process in manufacture of concrete mixture agents are described in the present paper. The experiments were performed in the differential scanning calorimetry(DSC), C 80 calorimeter, and thermal screening unit($TS^u$). The aim of the study was to evaluate the thermal stability of single material and mixture in esterification process. We provided the thermal data of chemical materials to present safe operating conditions through this study.

• 문화기술의 융합
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• 제9권5호
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• pp.569-582
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• 2023

납축전지는 가장 오래된 충전식 배터리 시스템으로 현재까지 충전식 배터리 분야에서 자리를 지키고 있다. 이 배터리는 다양한 이유로 열폭주 현상이 생기는데 이는 큰 사고로 이어질 가능성이 있다. 그렇기 때문에 열폭주 현상을 예방하는 것은 배터리 관리 시스템의 핵심부분이다. 최근에는 열폭주 위험 배터리 셀을 기계학습으로분류하는 연구가 진행 중이다. 본 논문에서는 비지도학습인 DBSCAN 클러스터링과 통계적 방법을 사용하여 열폭주 위험 셀 탐지 및 검증 알고리즘을 제안하였다. BMS에서 측정한 lead-acid 배터리의 저항 값만을 사용하여 열폭주 위험 셀 분류 실험을 진행하였고 본 논문에서 제안한 알고리즘이 열폭주 위험 셀을 정확히 검출해 냄을 보여주었다. 또한 본 논문에서 제안한 알고리즘을 사용하여 배터리 내 열폭주 위험이 있는 셀과 노이즈가 심한 셀을 분류할 수 있었으며 그리드 서치를 통한 DBSCAN 파라미터 최적화를 통해 열폭주 위험 셀을 초기에 검출해 낼 수 있었다.

• 한국안전학회지
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• 제27권5호
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• pp.77-87
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• 2012

Compared to a batch reactor, where all reactants are initially charged to the reactor, the semi-batch reactor presents serious advantages. The feed of at least one of the reactants provides an additional way of controlling the reaction course, which represents a safety factor and increases the constancy of the product quality. The aim of this study was to investigate the characteristics of thermal hazard such as a feed time, catalysis concentration and solvent concentration in methylthioisocyanate(MTI) synthesis reaction process. The experiments were carried out by the Multimax reactor system and Accelerating rate calorimeter(ARC). The MTI synthesis reaction process has many reaction factors and complicated reaction mechanism of multiphase reaction. Through this study, we can use as a tool for assessment of thermal hazard of other reaction processes by applying experiment method provided.

• 한국안전학회지
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• 제27권4호
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• pp.20-25
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• 2012

The purpose of this study is to analyze the thermal characteristics and to study fire hazard of electric leakage by iron power accumulated on circuit breaker in an iron processing factory. The thermal characteristics were analyzed while current was applied to the powder for ten minutes. Results showed that temperature of iron powder at 100 mA is $160^{\circ}C$ and at 175mA is $240^{\circ}C$. The sparks have occurred as iron powder drops between two(hot line and neutral line) wires and then iron powder explosion occurred while dropping continuously the iron powder on two lines. Those who work in the iron processing industry need to periodically remove and maintain the iron powder. The thermal characteristics in this paper can be used for electrical fire investigation and for basic data of thermal characteristic of leakage current through iron powder at iron processing factories.

• 환경위생공학
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• 제13권2호
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• pp.82-87
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• 1998

The opening temperature of emit heat, caloric value and decomposition hear were investigated by DSC & TGA in order to find the hazard of sanitary feed-stuff, also explosion hazard of dust was observed with electrical ignition after fodder dispersion by compressed air. Then opening temperature of emit heat of supporting gas. $O_{2}$ was much lower than inert gas. Ar. and caloric value increased 20. and the particle size of sanitary feed-stuff were appeared fire or explosion at 50/60 mesh and 60/80 mesh.

• International Journal of Safety
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• 제9권1호
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• pp.6-11
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• 2010

Thermal analysis, heating test on gram scale and simulation of exothermic behavior based on kinetic analysis has been conducted in order to evaluate thermal hazards of self-polymerization of MDI. The exothermic reactions of MDI are expected to be the polymerization which forms carbodiimide and carbon dioxide, dimerization and trimerization. When MDI is kept in adiabatic condition during 1 week (10080 hours), the simulated result shows runaway reaction can occur in the case that initial temperature was more than $130^{\circ}C$. The relationship between the initial temperature (T, $^{\circ}C$) and TMR is given in a following equation. TMR=$4.493{\times}10^{-7}$ exp ($9.532{\times}10^3$/(T+273.15)) We propose that the relationship gives important criteria of handling temperature of MDl to prevent a runaway reaction.

• 한국가스학회지
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• 제17권4호
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• pp.1-8
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• 2013

본 연구에서는 벌크 중합법을 이용한 폴리스티렌 중합공정의 폭주반응에 대한 열적 위험성을 가속속도열량계(ARC)와 소규모 반응열량계(MM)를 이용하여 평가하였다. 당해 중합공정은 반응온도 $120^{\circ}C{\sim}130^{\circ}C$로 운전되어져야 하며, $130^{\circ}C$ 이상의 반응온도에서는 반응 생성물의 급격한 점도 증가로 인하여 반응기의 온도제어 실패에 따른 폭주반응의 위험성이 존재하였다. 또한 당해 중합공정의 반응온도($120^{\circ}C{\sim}130^{\circ}C$)에서 공정운전 초기에 반응기의 냉각실패가 발생할 경우 폭주반응으로 인해 반응기의 온도와 압력이 각각 30 ~ 50분 이내에 약 $340^{\circ}C$, 5.3 bar 까지 급격히 상승하여 반응기의 파열판이 파열되거나 반응기가 폭발할 수 있는 열적 위험성이 높게 나타났다.

• 전기학회논문지
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• 제57권1호
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• pp.82-87
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• 2008

It is impossible to database(DB) the patterns of power cable events and cause analysis of faulted cable because the product liability(PL) law have been enforced in Korea, since 2002. In additions, simulation and pattern of power cable events are needed for DB system under accelerated deterioration. In this paper, we tested for resistance to cracking of cable below the 22.9kV class due to thermal stresses. This method of exam is following IEC 60811-3-1(Common test methods for insulating and sheathing materials of electric cables). From the results, The 22.9kV calss A power cable was discolored on the surface and significantly reduced in the longitudinal direction. As the thermal weight properties of A power cable was definitely varied, we are able to guess the problem of manufacture. If the cable was defect by the manufacture, the victims would be able to claim for damage in the PL system.

• 한국화재소방학회논문지
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• 제12권2호
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• pp.17-28
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• 1998

건물 화재시 예상되는 내장재의 실째 화재성농올 기준으로 한 위험성 명가방법올 제시하였다. 이률 위해 ISO Room Corner Test. (9705)를 기준으로 Qui ntie re의 화재확산 모델을 이용하여 내장재의 열 적 특성과 플래쉬 오버 도달시간과의 상관성을 유도하고 스쩨덴의 실제 시험결과와 비교 분석하였다. 이 결과, 내장재의 상대척인 화재위험성은 화재확산 변수 b륨 기준으로 명가될 수 있었다.