• Fire Science and Engineering
• /
• v.15 no.3
• /
• pp.14-20
• /
• 2001

The flash points are one of the most important fundamental properties used to determine the potential for fire and explosion hazards of flammable substances. A classification of the flash points is important for the safe handling of flammable liquids which constitute the solvent mixtures. Basic to all flash points behavior are vapor pressure and explosive limits(lower explosive limit and upper explosive limit). The flash points of flammable solvent mixtures can be calculated with the appropriate use of the fundamental laws of Raoult, Dalton, Le Chatelier and activity coefficient models. In this study, the reference values of lower flash points were compared with the calculated values by using Raoult's law and MRSM(modified response surface methodology) model. The lower flash points were in agreement with the predicted by Raoult's law and MRSM model. By means of this methodology, it is possible to evaluate reliability of experimental data of the flash points of the flammable mixtures.

• Fire Science and Engineering
• /
• v.28 no.4
• /
• pp.14-20
• /
• 2014

The purpose of this study is to analyze combustion patterns by filling a specific container with a flammable liquid and performing combustion tests in a divided space. The container used for the test is made of plastic, 20 mm in depth and 150 mm in width. After the liquid was ignited, its combustion process was photographed using a digital camera and video camera. It was found that in the case of benzene, the flame reached its peak at the fastest speed about 60 s while in the case of alcohol, the flame reached its peak at the lowest speed about 360 s, which is approximately six times slower than the benzene. In most cases, when the flame reached its peak, smoke generated was dark as the plastic container and flammable liquid were combusted simultaneously. After completion of the combustion, it was possible to sample oil vapor from all flammable liquids excluding soybean oil as a result of the examination of oil vapor using a crime investigation tube. That is, it can be seen that there is significant difference in flame propagation speed, pattern, etc., depending on the combustible substances.

• Fire Science and Engineering
• /
• v.13 no.1
• /
• pp.11-19
• /
• 1999

The flash point is generally used as a hazardous index of fire and explosion of a flammable liquid. A classification of the flash points is important for the safe handling of flammable liquids such as solvent mixtures. The flash points of pure substances and solvent mixtures can be c calculated with the appropriate use of the fundamental laws of Raoult, Dalton, Le Chatelier and a activity coefficient models. In this study, experimentally determined lower and upper flash points w were compared with the calculated values by using Raoult's law and van Laar equation. The flash points of pure substances were in agreement with the calculated values by vapor pressure and e explosive limits. Also, the lower flash points of M.E.K(methylethylketone)-toluene system were i in agreement with the predicted values by Raoult’s law, and the upper flash points were in a agreement with the predicted values by van Laar equation. By means of this methodology, it is possible to evaluate reliability of expermental data of the flash points of the flammable mixtures.

• Journal of the Korean Institute of Gas
• /
• v.25 no.6
• /
• pp.29-34
• /
• 2021

Flammable substances are often present in the raw materials of pharmaceutical products manufactured by pharmaceutical companies. In this case, an excessive amount of flammable substances is added to make an intermediate, and flammable substances that do not participate in the reaction are removed through filtration and drying steps. In addition, the flammable liquid separated in the filtration process is accumulated in the form of splash filling in the filtrate container. In this case, vapor and mist of flammable liquid are generated, which lowers the lower limit of explosion and minimum ignition energy, and increases the risk of fire and explosion due to complex charging. In this study, by analyzing fire accidents that occurred during the recent filtration process of pharmaceutical companies, it is proposed to prevent static electricity accumulation by measures of nitrogen supply facilities, capacity improvement, conductive filter fabric and so on.

• Analytical Science and Technology
• /
• v.35 no.6
• /
• pp.237-241
• /
• 2022

The effect of washing fingerprints deposited on glass that were contaminated with a flammable liquid (gasoline, kerosene, diesel, and thinner) was studied by washing with hexane or heptane. The fingerprints were visualized using fuming cyanoacrylate, followed by basic yellow 40 staining. After comparing the washing effect, by dividing one fingerprint into four sections, it was confirmed that the ridge detail was damaged by dissolving the fingerprints in flammable liquid. As a result of washing fingerprints contaminated with flammable liquids using hexane or heptane, fingerprints contaminated with gasoline, kerosene, and thinner did not show a washing effect because the ridge detail was damaged at the time of contamination, and only fingerprints contaminated with diesel exhibited improved ridge detail quality. Because hexane and heptane washing damage the ridge detail, it was found that fingerprints contaminated with gasoline, kerosene, and thinner were better enhanced directly without the washing process. In addition, it was found that the amount of the washing solvent and contact time should be minimized when washing fingerprints contaminated with diesel.

• Journal of ILASS-Korea
• /
• v.20 no.2
• /
• pp.101-106
• /
• 2015

Gas leakage and dispersion in the underground LNG power plant can lead to serious fire and explosion accident. In this study, computational fluid dynamics simulation was applied to model the dynamic process of gas leakage and dispersion phenomena in a closed space. To analyze the risk assessment factor, such as the flammable volume ratio, transient simulations were carried out for different scenarios. The simulation results visualized the gas distribution with time in the closed space. The flammable volume ratio was introduced for quantitative analysis the fire/explosion probability.

• International Journal of Safety
• /
• v.2 no.1
• /
• pp.34-38
• /
• 2003

The lower and upper flash points of the flammable binary system, butylacetate+2-propanol were measured by air blowing tester. The shape of the concentration-temperature region of flash depended on the components of the mixture in solution. The experimental data were compared with the values calculated by the reduced model under an ideal solution assumption and the flash point-prediction models based on Van Laar equation. Good qualitative agreement was obtained with these models. The prediction results of these models can thus be applied to incorporate inherently safer design for chemical process, such as the determination of the safe storage conditions for flammable solutions.

• Journal of the Korean Society of Safety
• /
• v.33 no.3
• /
• pp.33-38
• /
• 2018

Defects in piping caused by corrosion or external impact of underground piping can lead to high risk of rupture of the piping due to high pressure. Flammable gas can be immediately ignited when discharged from piping, causing a jetfire. The damage of the radiant heat not only threatens the health of the workers who work in the industry but also the health of the people living in the neighboring residential areas. It is important to prevent and prepare before an accident occurs. In this study, three types of flammable gas underground piping accident scenarios were investigated, and the ranges of influence were determined using Phast ver7.2. and finally regression models were formulated to predict the ranges using excel and Matlab.

• Journal of the Korean Society of Combustion
• /
• v.15 no.1
• /
• pp.38-42
• /
• 2010

Using a counterflow burner, downstream interactions between $CH_4$-air and $H_2/N_2$-Air premixed flames with various equivalence ratios has been experimentally investigated. Flame stability maps on triple and twin flames are provided in terms of global strain rate and equivalence ratio. Lean and rich flammable limits are examined for methane/air and hydrogen/nitrogen/air mixtures over the entire range of mixture concentrations in the interacting flames. Results show that these flammable limits can be significantly modified in the presence of interaction such that mixture conditions beyond the flammability limit can be still burn if it is supported by stronger flame. The experiment also discusses various oscillatory instabilities in a stability map.

• Journal of Mechanical Science and Technology
• /
• v.14 no.4
• /
• pp.426-432
• /
• 2000

The development of a low-pollution burner is important for saving energy and preserving the environment. A low-pollution burner can be produced by lean-mixture combustion and general combustion technology. The flammable limit of premixed flame is narrower than that of diffusion flame. Producing a lean mixture of fuel results in an effective combustion condition, which in turn produces high load and low pollution. In this study, it was found that the influx of $Q_2$ had an effect on extending the lean flammable limits and flame stabilization in a doubled jet burner. And the flame, consisting of small eddies, can be stabilized by the nozzle neck phenomena.