• Journal of the Korean Institute of Gas
• /
• v.3 no.2 s.7
• /
• pp.77-84
• /
• 1999

The XX company that is handling the class IV hazardous materials, located in Bu-Chon City and the LPG station in front of the XX company which is about 20 meters apart, was chosen as the standard model for this study In carrying out the consequence analysis, PHAST and Super-Chems were used for the study and utilizing the output of the simulation, we have evaluated the consequences throughout the probit analysis and explosion overpressure analysis. In case of Acetone, the effect distance of the damage on facilities-that is the result of radiation heat flux of $37.5kW/m^2$ by TNO model-is 68.51m by PHAST model and 40.93m by Super-Chem model. The risk assessment of the LPG station which is based on the explosion resulted as the analysis of the fire ball showed the diameter 125.2m, the height 206.2m and the duration 11.28sec and the effect distance for the radiant heat flux $37.5kW/m^2$ was 137.0m.

• Journal of the Korean Institute of Gas
• /
• v.11 no.2 s.35
• /
• pp.10-14
• /
• 2007

Flash point is one of the major physical properties used to evaluate fire hazards of the combustible liquids. Properties showing relative fire hazards of the combustible liquids are heat release rate(HRR), peak heat release rate(PHRR), time to ignition(TTI), mass loss rate, and yield of $CO/CO_2$. The relationships between flash points and fire properties of the combustible liquids were examined in this study. For this study, mass loss rate and time to ignition were measured to calculate fire properties of the combustible liquids. The results showed that good correlations could be found between flash point and time to ignition, time to peak heat release rate, and the propensity to flashover. From a presented results, the parameters can be used to evaluate relative hazards of the combustible liquids on fire.

• Fire Science and Engineering
• /
• v.31 no.4
• /
• pp.1-6
• /
• 2017

A fire resistance certification needs to be obtained before fire protection paint can be used in Korea. In the case of paint, the tests for certification are fire, gas hazard and bond strength. According to the hazard test standard of combustion gas, 16 mice are sacrificed every test. Therefore, there are ethical problems for the experimenter and legal problems for the laboratory. Accordingly, many alternatives are being assessed, such as combustion gas analysis, but they have not replaced animal testing yet. With gas hazard testing, the exhaust gas temperature can be measured. The property of the initial reaction of a specific fire paint can be characterized by this temperature. The purpose of this study was to consider the improvement point for a gas hazard test through comparative analysis of the exhaust temperature and the time of death of the mice.

• Journal of the Korean Institute of Gas
• /
• v.24 no.6
• /
• pp.11-17
• /
• 2020

In order to guarantee safe storage and transportation of a flammable liquid solution, it is very important to know its flash point information. In this paper, flash points of n-octane+n-nonane system and n-nonane+n-decane system were measured by Seta flash apparatus and an empirical equation is proposed for the accurate estimation of flash point. Empirical equation is used to predict flash point of n-octane+n-nonane system and n-nonane+n-decane system, which were also compared to Unifac-based model. Absolute average errors of flash point data predicted by Unifac-based model are 0.7℃ and 0.6℃ for n-octane+n-nonane system and n-nonane+n-decane system, respectively. Absolute average errors of flash point data predicted by empirical equation are 0.2℃ and 0.4℃ for n-octane+n-nonane system and n-nonane+n-decane system, respectively. In conclusion, empirical equation proposed in this paper, presented the most satisfactory.

• Fire Science and Engineering
• /
• v.31 no.3
• /
• pp.97-105
• /
• 2017

Because asphalt is a solid at normal temperature and is not a hazardous material as stipulated in the Safety Management Act on Hazardous Materials, it is often recognized as having no risk of fire or explosion. On the other hand, it is as dangerous as flammable liquid because it is heated to $170-180^{\circ}C$ and stored in a storage tank. This study analyzed the risk of fire and explosion during the storage and handling of asphalt and the actual conditions of asphalt regulations by fire service organizations. Moreover, this study analyzed the domestic case of explosions in the production process of asphalt concrete (ASCON) and domestic and foreign cases of asphalt storage tank explosions. The analysis suggested that unlike Japan, Korea has no asphalt regulations in fire service organizations. Explosions can occur when ignition is delayed after fuel is sprayed on the dryer drum burner of the aggregates during the production of ASCON. A physical explosion can occur in the storage tank when environmental purification facilities suddenly work strongly to remove air pollutants or bad smells during the heating of asphalt in an asphalt storage tank. In addition, explosions can occur when fires such as welding is performed in the asphalt storage tank.

• Fire Science and Engineering
• /
• v.30 no.6
• /
• pp.31-36
• /
• 2016

The flash point is one of the most important properties for characterizing the fire and explosion hazard of liquid solutions. In this study, the flash points of two flammable binary mixtures, n-pentanol + n-propanol and n-pentanol + n-heptanol systems were measured using a Seta flash closed cup tester. The flash point was estimated using the methods based on Raoult's law and multiple regression analysis. The measured flash points were also compared with the predicted flash points. The absolute average errors (AAE) of the results calculated by Raout's law were $1.3^{\circ}C$ and $1.3^{\circ}C$ for the n-pentanol + n-propanol and n-pentanol + n-heptanol mixtures, respectively. The absolute average errors of the results calculated by multiple regression analysis were $0.4^{\circ}C$ and $0.3^{\circ}C$ for the n-pentanol + n-propanol and n-pentanol + n-heptanol mixtures, respectively. According to the AAE, the calculated values based on multiple regression analysis were better than those based on Raoult's law.

• Journal of the Korean GEO-environmental Society
• /
• v.21 no.5
• /
• pp.23-33
• /
• 2020

As the scale of the economy expands, the number of cases of damage in enclosed spaces such as tunnels is increasing due to the accident of transportation vehicles of dangerous substances such as explosive flammable materials that have increased rapidly. In the case of road tunnels in particular, in the aspect of protection against the long-winding trend and the environment in the downtown area, the number of cases of passing through the downtown area increases, and securing the safety of structures against unexpected extreme disasters such as explosions during tunnel passage is very urgent. For this reason, developed countries are already conducting a review of internal bombardment, but there are almost no evaluation and countermeasures for explosion risk in Korea. Therefore, in this study, in order to evaluate the explosion safety of road tunnels, a boiling liquid explosive explosion (BLEVE), which is considered to have the greatest explosion load among vehicles driving on the road, is set as a reference explosion source, and the equivalent TNT explosion load is used for simulation of the explosion. A method of conversion was presented. In addition, by applying the derived explosion load, dynamic behavior simulation was performed by assuming various variables for the tunnel, and the explosion safety of the tunnel was analyzed.

• Journal of the Korean Electrochemical Society
• /
• v.22 no.4
• /
• pp.139-147
• /
• 2019

Lithium-ion battery (LiB) with high energy density and efficiency has been utilized for the electric vehicle (EV) and energy storage system (ESS) as well as portable devices. However, as explosion accidents have frequently happened till lately, all-solid-state lithium secondary battery (ALSB) began to get in a spotlight because it can secure a very high safety and energy density by substituting flammable organic liquid electrolyte to nonflammable inorganic solid electrolyte. In spite of ALSB's certain merits, it has shown much poorer performance of cells than one of LiB due to some challenges, which have been small or never dealt with in the LiB system. Hence, although plenty of studies made progress to solve them, an approach about design of all-solid-state electrode (ASSE) has been limited on account of difficulty of ALSB's experiments. That is why the virtual 3D structure of an all-solid-state electrode has to be built and used for the prediction of cell performance. In this study, we elucidate how to form the 3D ASSE structure and what to be needed for the simulation of characteristics on ALSB. Furthermore, the ultimate orientation of 3D modeling and simulation for the study of ALSB are briefly suggested.

• Journal of the Korean Electrochemical Society
• /
• v.21 no.4
• /
• pp.80-87
• /
• 2018

Safety issues in Li-ion battery system have been prime concerns, as demands for power supply device applicable to wearable device, electrical vehicles and energy storage system have increased. To solve safety problems, promising strategy is to replace organic liquid electrolyte with non-flammable solid electrolyte, leading to the development of all-solid-state battery. However, relative low conductivity and high resistance from rigid solid-solid interface hinder a wide application of solid electrolyte. Composite electrolytes composed of organic and inorganic parts could be alternative solution, which in turn bring about the increase of conductivity and conformal contact at physically rough interfaces. In our study, composite electrolytes were prepared by combining poly(ethylene oxide)(PEO) and $Li_7La_3Zr_2O_{12}$ (LLZO). The crystallinity, morphology and electrochemical performances were investigated with the control of LLZO contents from 0 wt% to 50 wt%. From the results, it is concluded that optimum content and uniform dispersion of LLZO in polymer matrix are significant to improve overall conductivity of composite electrolyte.

• Fire Science and Engineering
• /
• v.32 no.6
• /
• pp.34-39
• /
• 2018

In this paper, the architecture of a safe stove with an automatic fire suppression function using a sound wave fire extinguisher has been proposed and developed for the first time. A microcontroller connected to a fire sensor detects and suppresses a fire by driving a fire extinguisher. The sound wave fire extinguisher is composed of a speaker and collimator, and is driven by a driver module including an audio amplifier. The attenuation of the sound wave is reduced by preventing the sound diffusion with an enclosure surrounding a stove. The frequency of the sound wave is set to 50 Hz, and the sound pressure of 93 dBA is measured at the distance of 0.5 m. It takes maximum 8 and 15 seconds to suppress the flame from 7-cc and 14-cc flammable liquid, respectively, which corresponds to 24% and 42% of the natural extinguishing time. Since the proposed safe stove is non-toxic and leaves no residues over the conventional ones, it would combine with various home appliances to suppress early-stage fires and prevent fire expansion.