• Journal of the Korean Institute of Gas
• /
• v.11 no.2 s.35
• /
• pp.15-24
• /
• 2007

For consequence analysis at a gas explosion by vessel release, release rates, demage areas of facilities, and fatality areas were estimated and analyzed at various conditions(release materials, temperatures, pressures, and vessel types) by using the release scenario of API-581 BRD. Simulation results showed that release rates and consequences in the vessel release were higher than those in the pipe release, and the order of release rates and damage areas was as follows; tank>reactor>drum> column.

• Proceedings of the Korean Nuclear Society Conference
• /
• 1997.05a
• /
• pp.184-189
• /
• 1997

A prompt fission gas release model incorporating the resistance to gas flow in the gap was developed and the effects of gap resistance and failure location on prompt fission gas release from the cladding breach were assessed. The process of prompt fission gas release from the plenum and gap into the coolant was modeled in accordance with three major phenomena: (1) transient gas flow in the gap, (2) the growth of the fission gas bubble while it is still attached to the breach, and (3) the detachment of the fission gas bubble from the breach and mixing with the coolant. The cumulative mass release fraction by the present model was calculated for the case of Young-Gwang 3 & 4 nuclear fuel rod as a typical example. The results showed that the release behavior of prompt fission gas with time was different from the frictionless model which has frequently been used in a simplified approach, and that the location of cladding failure was another key factor for the prompt fission gas release process due to the resistance in the gap.

• Journal of the Korean Institute of Gas
• /
• v.10 no.4 s.33
• /
• pp.52-62
• /
• 2006

In this study, we tried to propose a selection method of release scenarios and a method of consequence analysis at a gas explosion by pipe release. Thus, release rates, damage areas of the facilities, and fatality areas were estimated and analyzed at various release conditions(temperature, pressure, release material, etc). As a results, we could conclude that the rupture was the worst case of release scenarios, and at release rates and damage areas were better estimated by the weighted average method considering a generic failure frequency of the release hole than by an arbitrary selection of the release hole.

• Journal of the Korean Institute of Gas
• /
• v.19 no.1
• /
• pp.51-56
• /
• 2015

To assess downward positions of water spray for the small-scale release of chlorine gas, dispersion coefficients for the Gaussian dispersion model were validated at the small-scale release experiment. And the downwind distances of water spray were assessed with the simulated results. As results, the Gaussian plume model using the Briggs' dispersion coefficient well estimated the dispersed characteristics for small-scale release of chlorine gas. The best adequate downwind position of water spray is the position of the maximum concentration of chlorine at the ground level. And the adequate vertical and horizontal dimensions of water spray consider the maximum width and height of cloud.

• Asian-Australasian Journal of Animal Sciences
• /
• v.12 no.5
• /
• pp.806-809
• /
• 1999

The present study showed the advantages of dried Bacillus subtilis culture (DBSC) supplementation on reducing ammonia gas release in the poultry house. In Experiment 1, 65-week-old Hyline W-36 hens were raised in individual wire-floor cages in a windowless house, and divided into two groups of 180 hens each. One group was fed diets without DBSC as the control and another group was fed a diet supplemented with 2% DBSC. In Experiment 2, 2-week-old broiler chicks were divided into 3 treatment groups of 20 chicks each and maintained in individual floor cages. One group was fed the diet without DBSC and other two groups were fed the diet supplemented with 1 or 2% DBSC, respectively. In experiment 1, DBSC consistently reduced ammonia gas release in the laying house (p<0.01) and manure storage facilities (p<0.01). incubation of feces for 1, 2, 3, 4, 5, 6, 24 or 48 hours showed that DBSC consistently reduced ammonia gas release. In Experiment 2, DBSC reduced ammonia gas release in the broiler house; however, DBSC had no effect on total N, urate-N and ammonia-N contents of feces, but it improved cumulative N utilization and decreased serum urea-N concentration when chicks when chicks were fed 1% DBSC.

• Journal of the Korean Institute of Gas
• /
• v.9 no.2 s.27
• /
• pp.43-49
• /
• 2005

Today toxic gas has various uses. If there is a release accident, the gas rapidly disperse into the atmosphere. The extent of damage due to toxic gas accident is very wide and fatal to human being. So, it is necessary for toxic gas facilities which have high risk to construct an emergency response system that prepare to toxic release and make immediate response to be possible at accident appearance. In this study accident scenario were selected and frequency analysis was executed using FTA technique. Dispersion effect of toxic gas release was analyzed using DNV company's PHAST(Ver. 6.2). Finally, an emergency response system was developed using results of quantitative risk analysis.

• Journal of the Korean Institute of Gas
• /
• v.8 no.1 s.22
• /
• pp.13-17
• /
• 2004

To evaluate suitability of the Gaussian plume model for the small scale release of a dense toxic gas, experimental concentrations of the small scale release of chlorine were compared with theoretical concentrations calculated by the Gaussian plume model using various dispersion coefficients. As a result, Ive found that the dispersion of chlorine gas was fairly varied with dispersion coefficient and atmospheric stability and that chlorine concentrations were well estimated by the Gaussian plume model using Briggs' dispersion coefficient and the effective release hight.

• Journal of the Korean Institute of Gas
• /
• v.16 no.4
• /
• pp.44-51
• /
• 2012

It is more important to realize safety management, medium-large accident prevention and risk prediction as accident of industry facilities can generate enormous physical and human damage because most energy plant might handle toxic substance. Especially, atmospheric dispersion system, which is able to simulate situation, have been used for release accident of toxic substance since the accident can show different of dispersion range and velocity according to release material, storage facility and atmospheric status. However those systems have been used generally in design step of industry facility and are difficult to deal with release accident quickly. Although some researches and cases have been studied for using real-time atmospheric information, there are insufficient system for processing quickly release accident. This paper aims to develop real-time smart atmospheric dispersion system that can deal with release accident quickly by enhancing distinct characteristics and efficiency of energy plant, and select release time and area using intelligent algorithm as accident prevention type.

• International Journal of Advanced Culture Technology
• /
• v.8 no.3
• /
• pp.211-215
• /
• 2020

Currently, most of the chlorine dioxide gas is processed at the beginning of storage or distribution. It has the disadvantage of not being able to continuously process gas since there is no system that can continuously process it during the distribution process. Therefore, in order to minimize changes in freshness and quality during the distribution process of agrifood, there is a need for a sustained-release chlorine dioxide gas treatment technology that can be continuously released. Therefore, in this study, the film to be used was examined so that the chlorine dioxide gas can be continuously released for a certain period of time, the concentration of the reactant and the viscosity at the time of the reaction were determined, and a chlorine dioxide gas gel pack was manufactured using this optimal condition. In addition, the gel pack was used to measure the amount of chlorine dioxide gas released and the sterilization effect of food poisoning bacteria.

• Journal of the Korean Institute of Gas
• /
• v.16 no.1
• /
• pp.15-21
• /
• 2012

An analysis was completed of the hazards distance of hydrogen accidents such as jet release, jet fire, and vapor cloud explosion(VCE) of hydrogen gas, and simplified equations have been proposed to predict the hazard distances to set up safety distance by the gas dispersion, fire, and explosion following hydrogen gas release. For a small release rate of hydrogen gas, such as from a pine-hole, the hazard distance from jet dispersion is longer than that from jet fire. The hazard distance is directly proportional to the pressure raised to a half power and to the diameter of hole and up to several tens meters. For a large release rate, such as from full bore rupture of a pipeline or a large hole of storage vessel, the hazard distance from a large jet fire is longer than that from unconfined vapor cloud explosion. The hazard distance from the fire may be up to several hundred meters. Hydrogen filling station in urban area is difficult to compliance with the safety distance criterion, if the accident scenario of large hydrogen gas release is basis for setting up the safety distance, which is minimum separation distance between the station and building. Therefore, the accident of large hydrogen gas release must be prevented by using safety devices and the safety distance may be set based on the small release rate of hydrogen gas. But if there are any possibility of large release, populated building, such as school, hospital etc, should be separated several hundred meters.