• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.10 no.12
• /
• pp.3761-3767
• /
• 2009

This study was investigated to determine the combustion characteristics, decomposition efficiency, and the flue gas concentrations after combustion in the high temperature reactor($1,250{\sim}1,400^{\circ}C$, 1 atm) for the liquid wastes(waste oil and waste solvent) generated from the industrial complex. The concentration of nitrogen oxide(NOx) is decreased and the synthetic gas is increased when the mass ratio of $O_2$/waste is about 1.53 because the reaction condition was changed to reduction state. And BTEXs(benzene, toluene, ethylbenzene, xylene) are decomposed more than 99.99%. If the highly concentrated liquid waste (waste oil and waste solvent) is treated under the operating conditions suggested by this study, our treatment method for the liquid waste was found to be proper because of the contaminants emission concentration is very low. In addition, the synthetic gas after combustion can be used as an alternative fuel.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2008.05a
• /
• pp.159-162
• /
• 2008

In this study, various cycles of liquid rocket engines were surveyed and specifically gas generator after burning cycle was investigated for upper stage motors. The engines for the upper stage can be categorized into three group based on the cycles and propellants at the diagram. Kerosene engines which adapt the gas generator after burning cycle and are located in the region II, are characterized for high combustion pressure and complexity. This cycle usually needs more than two pumps to use the turbine power efficiently. The fuel line can be divided into the gas generator line and the combustor line, and only the gas generator line is need to be pressured more because the combustion pressure in the gas generator is much higher than that of the combustor. Basically, all the oxidizer goes into the gas generator and than to the combustor, thus the auxiliary LOx pump is not critically necessary. However, for the various reasons, the LOx line requires a booster pump. A gas generator after burning cycle engines produces relatively high specific impuls than that of the open cycle engines. Thus it is suitable for upper stages of launch vehicles.

• Fire Science and Engineering
• /
• v.12 no.2
• /
• pp.43-59
• /
• 1998

It was studied a compared estimation of the fire risk of the three kinds of the interior materials, such as a resist carpet, a resist-after-treatment plywood and sofa leather. Toxic gases, CO, CO2, NOx, SO2, HCN, HCI were detected during the combustion of the samples. A resist-carpet was more combustible than the resist-after-treatment plywood and sofa leather in the combustion characteristics and has a blow-up-combustion of combustion in all the samples. The generation of CO reached the lethal doses in minute after the combustion was begun. NOx and So2 were detected not more than each of the lethal doses, while HCN was detected in the carpet 20.6 times than the sofa leather, and 4.6 times than the resist-after-treatment plywood. HCI was detected in the carpet 4.48 times than the sofa leather and 2.47 times than the resist-after-treatment plywood. It is conclusion that the carpet was the highest in the fire risk among the three kinds of the interior materials.

• Fire Science and Engineering
• /
• v.28 no.6
• /
• pp.8-12
• /
• 2014

Interior finishing materials using noncombustible were regulated by the building codes to prevent the spread of fire and protect occupants. The average deed of stopping time of experimental mouse exposing combustion gas were measured by KS F 2271 gas toxicity test. At that time, The average deed of stopping time under 9 minutes were judged a inconsistence. This experiment method has limit to find out a cause of toxicity effect factor. In this study, particle size analysis were performed for investigate a major factor.

• Fire Science and Engineering
• /
• v.21 no.3
• /
• pp.41-46
• /
• 2007

The combustion characteristics of surface forest fire fuels was analysed using variable external irradiation level. The characteristics such as ignition time, ignition temperature, critical heat flux and mass loss rate were measured. Fuel samples were exposed to incident heat fluxes from 8 to $50\;kW/m^2$. For the measurement of various combustion characteristics, the size of specimen holder was $100\;mm{\times}100\;mm{\times}12\;mm$ and the fuel samples grinded by electric mill were the fallen leaves of Quercus variabilis and Pinus densiflora. As results, the occurrence of ignition is possible to the heat flux more than $9\;kW/m^2$. The fuel of Pinus densiflora keeps its high temperature longer than that of Quercus variabilis during the combustion process. The results of measurement shows that the maximun and average mass loss rate of Quercus variabilis larger than that of Pinus densiflora.

• Fire Science and Engineering
• /
• v.20 no.4 s.64
• /
• pp.26-32
• /
• 2006

Nowadays in Korea, KS F 2271 has been using for the test of fire safety performance of sandwich panels. Smoke toxicity test is the test for the toxicity evaluation of smoke and hazardous gas, caused by combustion of building materials and finishing materials. Smoke toxicity can be evaluated by the mean incapacitation time of mice; however this method is not a quantitative way. This test result can be influenced by the health status of mice and test condition. Specific optical density can be quantitatively measured by ISO 5659-2 single chamber method and toxic gases can be quantitatively measured by FTIR analysis. In this study, specific optical density of sandwich panel insulations, which are widely used in Korea, were tested using the ISO 5659-2 single chamber test method and compared with each test. Also, in the second test of three tests for each specimen, FTIR analysis was performed and quantitative test results(HCl, $NO_2$, etc) were compared with each test result.

• Fire Science and Engineering
• /
• v.15 no.3
• /
• pp.36-43
• /
• 2001

Several types of widely used interior upholsteries including wallpaper, veneer board and floor cover, were selected to be evaluated by using the method of NES 713 text. Test results indicates that a fire with retardant wallpaper release a large amount of toxic gases when constantly exposed to a fire source. When evaluated in terms of the masses of released gases, the release of Carbon monoxide appears the highest in case of wallpaper fire, while the ratio of CO/Mass loss appears the highest in case of floor cover fire. Therefore, it can be concluded that, a large amount of toxic gas will release from a floor cover fire with even a small quantity of fuel.

• Fire Science and Engineering
• /
• v.12 no.4
• /
• pp.41-49
• /
• 1998

In this study, the thermal improvement of an isophthalic acid polyester resin by the incorporation of flame retardants has been investigated. Aluminium hydroxide, antimony oxide and alumina powder were used to formulate the flame retardant systems. The improvement of an isophthalic resin by incorporating aluminium hydroxide is dramatic(burning rate and smoke emission are reduced), although the mechanical property is decreased significantly. The addition of small amount(2.5 phr) of antimony oxide produces high char yield(31%) which acts as a protective layer on the surface of the resin.

• Fire Science and Engineering
• /
• v.25 no.5
• /
• pp.69-75
• /
• 2011

It was performed to test the combustive properties of low density polyethylene and ethylene vinyl acetate (LDPE-EVA) composite by the addition of magnesium hydroxide. Flame retardant of natural magnesium hydroxide was added to the mixture of LDPE-EVA in 40 to 80 wt% concentration. The composite was compounded to prepare specimen for combustive analysis by cone calorimeter (ISO 5660-1). Comparing with virgin LDPE-EVA, the specimens including the magnesium hydroxide had lower flashover possibility. It is supposed that the combustive properties in the composites decreased due to the endothermic decomposition of magnesium hydroxide. The specimens with magnesium hydroxide showed both the lower total heat release rate (THR) and lower CO production rate than those of virgin polymer. As the magnesium hydroxide content increases, the total smoke release (THR) and smoke extinction area (SEA) decreased.

• Fire Science and Engineering
• /
• v.25 no.5
• /
• pp.47-53
• /
• 2011

Fire load in buildings greatly contribute to the time and scale of fire according to the type and quantity of the fire load. Because bookstores have a large quantity of fire load compared with other buildings which may lead to large scale fires, however, their heat release characteristics have been hardly investigated. In this study, to obtain the data applicable for the performance-based fire safety design of bookstores, the specimens representing stacked fire loads were heated in a furnace in compliance with the standard heating curve of ISO834-1:1999 to investigate their heat release characteristics. From the experiment result, the combustion velocity and heat release rate required for performancebased fire safety designs are obtained.