• Journal of the Korean Institute of Gas
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• v.2 no.2
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• pp.55-60
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• 1998

In this study, we investigated the dust explosion characteristics by determining minimum ignition energy and explosion limit for this experiment, we used pine-tree dust which was used widely for the filler of thermosetting resin. The experiment was accomplished according to the variation of discharge gap, dust concentration, particle size and humidity. The result of this experiment are as follows; (1) The relation between the discharge gap and ignition energy was that ignition energy decreased according as the discharge gap became small, but increased when the discharge gap was below 4mm and suddenly became infinite when the discharge gap was below. So, we knew that this infinite value was limit discharge gap. (2) When the dust concentration increase and the particle size became microscopic it was easy to explore and in the same particle size, if the humidity increase the minimum ingnition energy decreased.

• Explosives and Blasting
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• v.12 no.3
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• pp.32-41
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• 1994

The specific characters in recent Chemical processing and industrial plants are the handling of severe limit conditions such as high pressure, high and low temperature, high speed production and transportation plant automation and appearance of many new hazardous materials in numbers and quantity. The possibilities of these characters causing the accident and environmental pollution in industrial activities become very high. This paper describes the concrete policy In prevent the explosion accident out of the many accidents which are the safety of the safety engineering.

• Journal of the Korea Safety Management & Science
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• v.4 no.3
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• pp.35-43
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• 2002

For the unconfined vapor cloud explosion accident by the continuous release of gas-liquid flow of various saturated liquids in a vessel at ground level, overpressures were estimated and analyzed with various release conditions and materials by TNT equivalency model with vapor dispersion. We found that at same release conditions, overpressure showed n-heptane > xylene > n-hexane > toluene > n-heptane > benzene, respectively and that overpressure was increased with increasing the hole diameter and the storage pressure, but it was increased with decreasing the wind speed, the interested distance, and the vessel thickness.

• Proceedings of the Korean Nuclear Society Conference
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• 2004.10a
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• pp.381-382
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• 2004

• Journal of the Korean Society of Safety
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• v.26 no.6
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• pp.26-30
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• 2011

Experimental investigations were performed to examine the effects of different electrostatic discharge ignition energies on LPG/air mixture explosions in an explosion chamber. The chamber consisted of 500 mm in length, with a $100{\times}100mm^2$ cross section. Three different ignition energies were used: 0.30 mJ, 46 mJ and 98 mJ. Flame propagations were recorded by a high speed video camera. The results of flame speed and pressure obtained from the different ignition energies were discussed. It was found that as the energy increased, different flame initiations occurred. This caused the time interval in both the flame and pressure developments. It was also found that the flame speed and the pressure were less sensitive to both 0.30 mJ and 46 mJ, except for the ignition energy of 98 mJ.

• Korean Chemical Engineering Research
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• v.60 no.2
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• pp.229-236
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• 2022

An experimental investigation was conducted on the influences of median size, dust concentration, dust condition (cloud and layer) for the fire and explosion hazard assessment of dusts with the same powder property. For this purpose, tests have been performed in accordance with 20 L explosion sphere, thermogravi- metric analyze, combustion rate tester (UN method). We investigated the explosion characteristics and flame propagation velocity (FPV) in dust cloud and the flame spread velocity(FSV) over dust layer on 8 dust samples with different particle sizes of 4 types of dusts (Sugar, Mg, Al, Zr). An explosion hazard increased with decreasing particle size in Mg and Al dust clouds, but sugar did not show the effect of explosion hazard due to particle size change in dust clouds. The flame propagation velocity (FPV) of suspended dusts increased significantly when the particle size decreased from micro to nano than the variation of particle size in micro range. The flame spread velocity (FSV) over dust layer showed a tendency to increase over the inclined dust layers (30° slope) rather than the horizontal dust layers (0° slope). The flame spread rate (FSV) over dust layers increased on the inclined dust layer (30° slope) rather than the horizontal dust layer (0° slope) and was higher upward flame than the downward flame in condition of inclined dust layers(30° slope).

• 한국방재학회:학술대회논문집
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• 2007.02a
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• pp.405-409
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• 2007

This paper focused on the way of prevention of disaster in the accident of explosion when the fire broke out in the boiler room where installed the basement of the building, and showed the effective ways for sustaining people and property safely in the view of problems and improvement of the law and safety awareness of people.

• Journal of the Korean Institute of Gas
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• v.19 no.6
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• pp.54-61
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• 2015

A series of CFD calculation has been conducted to investigate the effect of facility confinement on explosion power for process plant facility. The level of confinement of a facility was simplified with VBR(volume blockage ratio) and averaged size of obstacles. FLACS which is 3D CFD code of gas dispersion and the explosion was used for simulating the explosion phenomena in the idealized domain with different confinement level. The CFD results showed a tendency that the overpressure increases with increasing VBR and number of obstacles. The effect of VBR on the overpressure was relatively small for the case of number of obstacle less than 25. The results of this study can be used to provide a safety guideline considering the facility confinement in case of leakage accident of flammable gas and vapor in process plants.

• 한국가스학회:학술대회논문집
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• 2001.10a
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• pp.299-304
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• 2001

• Journal of the Korean Institute of Gas
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• v.22 no.4
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• pp.27-31
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• 2018

Classification of explosion hazard areas is very important in terms of cost and safety in the workplace handling flammable materials. This is because the radius of the hazardous area determines whether or not the explosion-proof equipment is installed in the electrical machinery and apparatus. From November 6, 2017, KS C IEC-60079-10-1: 2015 will be issued and applied as a new standard. It is important to understand and apply the difference between the existing standard and the new standard. Leakage coefficients and compression factors were added to the leakage calculation formula, and the formula of evaporation pool leakage, application of leakage ball size, and shape of explosion hazard area were applied. The range of the safety factor K has also been changed. Also, in the radius of the hazardous area, the existing standard applies the number of ventilation to the virtual volume, but the revised standard is calculated by using the leakage characteristic value. In this study, we investigated the differences from existing standards in terms of ventilation and dilution and examined the effect on the radius of the hazard area. Comparisons and analyzes were carried out by applying revised standards to workplaces where existing explosion hazard locations were selected. The results showed that even if the ventilation and dilution were successful, the risk radius was not substantially affected.