• Environmental Analysis Health and Toxicology
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• 제7권3_4호
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• pp.81-84
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• 1992

Physical compositions of solid waste in Wonju, shopping area were investigated with combustibles 78.13% (papers 35.89%, foods 14.41% etc.) incombustibles 21.87% (glass and ceramics 11.02%, metals 6.0% etc.) in 1991, solid waste in apartment area were investigated with combustibles 84.27% (foods 34.29%, papers 22.58% etc.), incombustibles 15.73% (glass and ceramics 8.77%, metals 4.85% etc.) and residence area were characterised with combustibles 70.37% (foods 33.55% , papers 10.53% etc.) and incombustibles 29.63% (ash of briquet 17.29%, glass and ceramics 7.49% etc.). Water qualities of a leachate from municipal landfill of Wonju city were analysed pH 8.0~8.4, total suspended solid 102~140 mg/1, CN￣ 0.003~ 0.008 mg/1, NO$_2$-N 0.108~0.294 mg/1 and phenols 0.46~1.12 mg/1. Volume of the leachate for 20% methemoglobin formation were 0.2~0.4 mg/ml in Octever, 0.3~0.4 ml/ml in December sampling, 0.2~0.3 ml/ml in St.1 and 0.4 ml/ml in St.3.

• 한국환경과학회지
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• 제17권2호
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• pp.177-183
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• 2008

Characteristic of wastes in a unsanitary landfill at the residential development site in H city, Kyunggi-do was investigated for the disposal of huge amount of wastes. The total amount of wastes was estimated at 117,000 ton and construction solid wastes and municipal solid wastes were detected together. The portion of combustibles was very low and soils, concrete wastes, and pebbles were the major components in landfilled wastes. Because the site was the residential development site, the landfilled wastes should be removed immediately for the construction. Therefore the way that the unsanitary landfill was excavated and the wastes were sorted into three categories such as soils, noncombustibles and combustibles was selected as the best method. Soils and noncombustibles could be recycled and sorted combustibles could be re-landfilled in a smaller area or incinerated.

• 한국화재소방학회논문지
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• 제31권3호
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• pp.41-48
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• 2017

고체 연료의 열물성 변화가 가연물의 열분해 특성에 미치는 영향을 고찰해 보기 위해서 KS F ISO 5660-1에 제시된 콘 칼로리미터 실험을 수행하였고, Fire Dynamics Simulator (FDS) 1차원 열분해 모델의 수치해석을 수행하였다. 고체 연료로는 열분해과정 중 Char를 발생시키지 않는 Poly Methyl Methacrylate (PMMA)를 사용하였으며, 문헌에 보고된 PMMA의 열물성치와 열분해 물성치를 FDS의 입력 변수로 설정하여 콘 칼로리미터 실험의 수치해석을 수행하였다. 콘 칼로리미터 실험을 통해 측정된 고체가연물의 질량 감소 결과와 일치하는 열분해 모델의 계산 결과를 바탕으로 열물성치와 열분해 물성치의 변화가 고체 가연물의 질량 감소에 어떠한 영향을 주는지를 고찰해 보았으며, 열전도계수와 비열을 상온의 상수 값으로 입력한 경우 가연물의 질량 감소의 예측에 있어 상당한 오차를 유발할 수 있다.

• 산업기술연구
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• 제22권B호
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• pp.103-108
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• 2002

This research was performed to investigate the generation and physico-chemical characteristics of municipal solid wastes. The results were as follows: i) The generation rate and bulk density were 0.157 kg/cap/d and 147.8 g/L in residential zone, respectively. In non-residential zone, the generation and bulk density were 1.71 kg/cap/d and 85.6 g/L, respectively. Consequently, bulk density of non-residential zone was lower than that of residential zone. ii) The wastes consisted of 90% of combustibles and 10% of incombustibles in residential zone. And the wastes from non-residential zone was composed 85% of combustibles and 15% of incombustibles. iii) Water content was estimated at 47~50% in residential zone and restaurants. In non-residential zone, except restaurants, water content was in the range of 10~30%. Ash content was nearly 10% in overall zone.

• 한국화재소방학회논문지
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• 제34권3호
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• pp.28-34
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• 2020

고체 가연물 주위의 유동과 열적 두께의 변화가 열방출률 특성에 미치는 영향을 고찰해보기 위해 ISO 5660-1 콘 칼로리미터 실험을 수행하였다. 고체 가연물로는 연소반응 중 Char를 발생시키지 않는 Polymethyl methacrylate (PMMA)를 선정하였고 열침투깊이를 계산하여 PMMA의 열적 두께를 구분하였다. 콘 칼로리미터의 덕트 유동을 12, 24, 40 L/s로 설정하여 가연물 주위에 강제 유동을 발생시킨 뒤 PMMA의 연소 시 측정된 열방출률을 측정함으로써 열분해 특성을 분석하였다. 열적으로 얇은 가연물의 열방출률은 주위의 유동 변화에 크게 영향을 받지 않았지만, 열적으로 두꺼운 가연물은 유량의 변화에 따라 열방출률이 크게 영향 받는 것을 확인하였다.

• 한국안전학회지
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• 제8권4호
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• pp.107-113
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• 1993

Small rectangular explosion chamber of its size 25cmX25cmX32cm with a circular bursting diaphram at the top was used to study the mechanism of gas explosion to fire transition phenomena, the process of ignition of solid combustibles during a gas explosion. To visulize the explosion to fire transition phenomena, transparent acryl window and high speed camera system were used. The test piece of solid combustible in this experiments was a 5cm$\times$5cm square sheet of newspaper which was placed in the explosion chamber filled with a LPG-air mixture. The mixture was ignited by an electric spark at the center of the chamber. Explosion to fire transition phenomena and the behavior of out flow and in flow of gas through the opening yielded by bursting the diaphram was visualized with shlieren system and without shlieren system. Diameter of a bursting dlaphram at the top of the explosion chamber was varied 5cm, 10cm, and 15cm, and the position of test piece were varied with 6 point. Explosion pressure was measured with strain type pressure transducer, and the weight difference of the test piece before and after each experimental run was measured. By comparing the weight difference of solid combustibles before and after the experiment and the behavior of out flow and inflow of gas after explosion, it was found that the possibility of ignition was depends on the LPG-air mixture concentration and the exposure period of test piece to the burnt gas. Test result of this experiments it was found that the main factor of this phenomena are that heat transfer to the test piece, and the pyrolysis reaction of test piece. Based on the results, the mechanism of the explosion to fire transition phenomena were inferred ; gas explosion- heat transfer to solid combustibiles ; pyrolysis reaction of solid combutibles : air inflow ; mixing of the pyroly gas with air ignition.

• 환경위생공학
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• 제20권1호
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• pp.1-11
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• 2005

This research was performed to investigate the generation and physico-chemical characteristics of municipal solid wastes in the east coast of gangwon. The results were as follows: i) The generation rate of G city and Y gun were 0.187-0.384 $\cal{kg/cap/d}$ and 0.136-0.259 $\cal{kg/cap/d}$. Apparent density of G city and Y gun were 137.9-191.9 g/L and 157.3-238.3 g/L, respectively. ii) The wastes consisted of $76.1-97.5\%$ of combustibles and $2.5-23.9\%$ of incombustibles in G city. And the wastes consisted of $73.7-98.6\%$ of combustibles and $1.4-26.3\%$ of incombustibles in Y gun. Most of municipal solid wastes are composed of food, paper, and vinyl-plastics waste. Water content of commercial area, agricultural resident, detached resident, apartment area, school zone were 42.5-45.9, 37.6-43.4, 32.4-38.4, 29.3-32.3, $6.8-26.9\%$, respectively. iii) The low heating value of G city and Y gun were 1,125.5-2,540.7 $\cal{kcal/kg}$, 1,104.4-2,062.3 $\cal{kcal/kg}$, and school and apartment area were higher than commercial area.

• 한국화재소방학회논문지
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• 제18권2호
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• pp.20-26
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• 2004

본 논문은 가스폭발로부터 화채로의 전이현상 및 전이 방지 연구를 위해 가로 세로 높이가 각각 $100 cm {\times} 60 cm {\times} 45 cm$인 폭발용기를 사용하여 폭발 후 화재로의 전이현상을 고속 비디오로 가시화하고 가시화된 영상을 분석하여 그 기구들을 확인하였다. 고체 가연물로는 신문용지를 가로 세로가 $30cm {\times} 20cm$크기로 절단하여 사용하였고 LPG-공기 혼합가스는 10㎸ 전기 스파크를 사용하여 점화시켰다. 실험 변수로는 혼합가스의 농도, 개구부의 크기 및 가연물의 위치 등이었으며, 파열면의 크기는 $10cm {\times} 9cm, 13cm {\times} 10cm, 27cm {\times} 20cm, 40cm {\times} 27cm$로 하였고 가연물의 설치 위치는 4종류로 하였다. 폭발 후 전이 방지 기구의 고찰은 가스 소화약제인 이산화탄소를 이용하여 실험하였다. 실험 결과 가스폭발로부터 화재로의 전이 현상은 혼합가스의 농도와 고온의 화염 및 연소가스에 노출되는 시간에 많은 영향을 받으며 폭발 후 분위기의 냉각이나 불활성화를 통해 화재로의 전이를 방지 할 수 있음을 알 수 있었다.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2008년도 춘계학술대회논문집
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• pp.80-83
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• 2008

The characteristics of the spread of a forest fire are generally related to the attributes of combustibles, geographical features, and meteorological conditions, such as wind conditions. The most common methodology used to create a prediction model for the spread of forest fires, based on the numerical analysis of the development stages of a forest fire, is an analysis of heat energy transmission by the stage of heat transmission. When a forest fire breaks out, the analysis of the transmission velocity of heat energy is quantifiable by the spread velocity of flame movement through a physical and chemical analysis at every stage of the fire development from flame production and heat transmission to its termination. In this study, the formula used for the 1-dimensional surface forest fire behavior prediction model, derived from a numerical analysis of the surface flame spread rate of solid combustibles, is introduced. The formula for the 1-dimensional surface forest fire behavior prediction model is the estimated equation of the flame spread velocity, depending on the condition of wind velocity on the ground. Experimental and theoretical equations on flame duration, flame height, flame temperature, ignition temperature of surface fuels, etc., has been applied to the device of this formula. As a result of a comparison between the ROS(rate of spread) from this formula and ROSs from various equations of other models or experimental values, a trend suggesting an increasing curved line of the exponent function under 3m/s or less wind velocity condition was identified. As a result of a comparison between experimental values and numerically analyzed values for fallen pine tree leaves, the flame spread velocity reveals has a error of less than 20%.

• 한국연소학회:학술대회논문집
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• 한국연소학회 1999년도 제19회 KOSCO SYMPOSIUM 논문집
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• pp.81-91
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• 1999

Fuel characteristics of sewage sludge as required for the fluidized bed incinerators have been evaluated. Sewage sludge is basically a solid fuel with high percentage of moisture. Moisture content of the fuel directly affects the heating value of the fuel and the exhaust gas composition. When the sludge of transported into the incinerator, sludge cake is subject to the mixing, break-up and heat-up. Fluidization process would enhance these physical processes. The sludge fuel could then undergo the moisture evaporation and devolatilization process. Subsequent oxidation of volatiles as well as the remaining char would then follow. Sludge samples are characterized with high percentage of volatiles out of total combustibles. Quantitative understanding of above listed subprocesses would certainly help in the utilization of fluidized bed incinerators. A limited set of fuel characterization tests including calorimetric analysis, proximate analysis, elemental analysis and thermogravimetric analysis were conducted for the selected sludge samples. The measurement reasults of sludge samples were reported along with some published data. Limited experience in the actual incinerator plant is also presented.