• Journal of the Korean Institute of Gas
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• v.17 no.6
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• pp.27-32
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• 2013

Renewable gas fuels such as biogas and landfill gas are obtained from the biodegradable organic wastes so that they inherently have carbon-neutral nature which can respond global warming. Therefore, attentions are paid to use this renewable gases as a main fuel for internal combustion engines. However, the composition of the fuel varies by its origin or conversion process, it is necessary to make stable combustion and accomplish high efficiency when used in power generating spark ignition (SI) engines. In this study, efforts have been made to investigate the effect of the composition of renewable gas fuel on the engine performance and exhaust emissions. In addition, a new spark plug with a long electrode was tested and compared with a base spark plug as a way to improve engine efficiency and reduce harmful emissions.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2001.04a
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• pp.98-103
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• 2001

In order to understand the characteristics of leachate at the Seokdae municipal waste landfill in the Pusan city, the correlation between leachate pollution loading and volume of gas production. concentration of gas and subsidence of ground, the characteristical methos, geochemical analyses and laboratory column tests using samples of gases, leachate and surface soil of Seokdae waste landfill area. Through the analysis of water balance, leachate flow rate and pollution loading were estimated. Geistatistical analysis of four gas components ( $O_2$, C $H_4$, $H_2$S and CO) shows the possibility of ground subsidence around the group of a site with high concentration of gas. From geochemical analyses of leachate, EC and Total-Alkalinity of ground subsidence around the group of a site with high concentration of gas. From geochemical analysis of leachate, Ec and Total-Alkalinity were increased, and Cl, Cr, Mn, Cu, Zn, Cd and Pb were decreassed comparing to the part, and the type of water quality was Na-HC $O_3$ in trilinear diagram. It shows that biodecomposition of municipal wastes continues actively. From the analysis of water balance, the total leachate flow rate is about 465.11㎥/day and pure pollution loading of Cl, Mn and Fe are estimated to 223.8kg/day, 0.2kg/day, 0.3kg/day, respectively. The laboratory column test of residual soil and landfill soil shows 0.206cm and 0.019cm for linear velocity(equation omitted), 0.234 $\textrm{cm}^2$/min and 0.018$\textrm{cm}^2$/min for diffusion coefficient ( $D_{ι}$), and 1.136cm and 0.095cm longitudinal dispersion index ($\alpha$$_{ι}$), respective]y. It demonstrates that the delay time of contamination for residual soil is shorter than that of landfill soil.

• Analytical Science and Technology
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• v.14 no.3
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• pp.274-285
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• 2001

In this study, the thermal desorption-cryofocusing-gas chromatographic(TD-C-GC) method was developed for determination of volatile organic compounds(VOCs) in ambient air and was applied at the municipal solid waste landfill sites. On-column cryofocusing was possible only with a 100 ml dewars bottle in TD-C-GC method with a stainless steel column. However, high operating pressure was needed for purging VOCs from the absorbent trap, which was able to solve by pressure programming with a electric pressure controller. By using both pressure and temperature programming brought increasing of resolution power in on-column cryofocusing method, but the high pressure caused a leakage of sample tube with repeated use. A loop cryofocusing devise was also developed and compared with the direct on-column method. In loop cryofocusing method, VOCs were concentrated on a 0.8mm i.d. loop which is located between the injector and separation column by using liquid nitrogen. In order to purge VOCs from the absorbent trap, only 0.4 psi of pressure was need in the loop cryofocusing method. Dual detection system was applied for the analysis of VOCs; a FID was used for hydrocarbons and a FPD was used for sulfur-containing compounds. Qualitative analysis was done by on-column cryofocusing GC-MS system. Among the large number of VOCs, toluene was the most abundant. Hydrogen sulfide, dimethyl sulfide, carbon disulfide, dimethyl disulfide and methyl propyl disulfide were detected at landfill site by FPD.

• Journal of Korea Soil Environment Society
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• v.3 no.1
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• pp.83-92
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• 1998

This study presents a relationship between gas quantity and measurement resistance using the bubble meter, the water head indicator and the rotor meter from the gas vent sanitary landfill. From the one-dimensional analyses and experiments, the below results have been obtained. The gas volume sourcing from the gas vent depends on the permeability of final cover soil, its cover depth and distance between the gas vents. The total gas volume producing in the interested domain may be accurately measured by the bubble meter, the water head indicator and the rotor meter if the clay is used for the final cover soil. The required times approaching to the steady-state are different with respect to the flow meters, one day is for the bubble meter and the water head indicator and one hour for the rotor meter.

• Microbiology and Biotechnology Letters
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• v.37 no.4
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• pp.293-305
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• 2009

Methane, as a greenhouse gas, is some 21~25 times more detrimental to the environmental than carbon dioxide. Landfills generally constitute the most important anthropogenic source, and methane emission from landfill was estimated as 35~73 Tg per year. Biological approaches using biocover (open system) and biofilter (closed system) can be a promising solution for older and/or smaller landfills where the methane production is too low for energy recovery or flaring and installation of a gas extraction system is inefficient. Methanotrophic bacteria, utilizing methane as a sole carbon and energy source, are responsible for the aerobic degradation (oxidation) of methane in the biological systems. Many bench-scale studies have demonstrated a high oxidation capacity in diverse filter bed materials such as soil, compost, earthworm cast and etc. Compost had been most often employed in the biological systems, and the methane oxidation rates in compost biocovers/boifilters ranged from 50 to $700\;g-CH_4\;m^{-2}\;d^{-1}$. Some preliminary field trials have showed the suitability of biocovers/biofilters for practical application and their satisfactory performance in mitigation methane emissions. Since the reduction of landfill methane emissions has been linked to carbon credits and trading schemes, the verified quantification of mitigated emissions through biocovers/biofilters is very important. Therefore, the assessment of in situ biocovers/biofilters performance should be standardized, and the reliable quantification methods of methane reduction is necessary.

• Analytical Science and Technology
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• v.17 no.3
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• pp.251-262
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• 2004

It is for the purpose of investigating the tritium distribution in the leachates, the raw and treated leachates and the condensates of the methane gas, which have occurred from domestic solid waste landfills. Also it aims to measure the tritium distribution level on the colloid size of the leachates, the raw and treated leachates. It was found that the major inorganic contaminants of the leachates were Na, K, Ca, Mg, $NH{_4}^+$-N and $Cl^-$. The mean tritium level of the raw leachates of the investigated 13 landfill sites for 6 months was 17 ~ 1196 TU. It corresponded to a several scores or hundreds of magnitude higher value than that of the normal environmental sample level except for two landfill sites. Also such a high concentration of the tritium was found in the treated leachates and methane gas condensates as well. Nevertheless it is important to emphasize that the tritium level which was found in this research is about 100 times lower than the tritium limit for the drinking water quality. And most of the tritium existed in the dissolved colloid of the leachate of which the colloid size is below $0.45{\mu}m$. Also, according to the tritium analysis results of the leachates after filtration with $0.45{\mu}m$ membrane filter for some landfills, it is likely that some tritium of the leachate would be distributed in a colloid size over $0.45{\mu}m$. In general the relationship between the tritium and other contaminants in the raw leachate was low, but it was relatively high between the tritium and TOC. However, the tritium content in the leachate had no meaningful relationship with the scale, hydrological characteristics and age of the landfill.

• Journal of Korean Society for Atmospheric Environment
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• v.14 no.5
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• pp.499-506
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• 1998

Recently almost wastes except recycled garbage are dumped into landfill site in Korea. Landfills are significant compounds (NMOCS) are produced. NMOCS include reactive volative organic compound (VOC) and hazardous air pollutants. LAEEM (Landfill Air Emissions Estimation Model) developed by Control Technology Center, V.S. EPA is used to estimate a mount of landfill gas from all landfills. As the result, landfill gas 4,121,000 ton, carbon dioxide 2,951,000 ton, methane 1,1120,000 ton are estimated as emissions from all landfills in Korea.

• Journal of the Korea Safety Management & Science
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• v.3 no.3
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• pp.201-211
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• 2001

The most general treatment method of municipal solid waste is a landfill. The LFG (landfill gas) migration is a serious problem in environmental aspect. The object of this study is to present the possibility of LFG utilization as a replacement or supplementary fuel for local energy -demand. We have developed the EXCEL program for the economic analysis.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 1999.11a
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• pp.71-74
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• 1999

최근 들어 자동차 보유대 수의 급격한 증가와 함께 폐타이어의 발생량도 급격히 증가하였다. 폐타이어의 발생량이 적었을 때는 매립이나 소각 등의 방법으로 폐타이어를 처리해도 별 문제가 발생하지 않았다. 그러나, 폐타이어 발생량이 급격히 증가한 요즈음은 발생된 폐타이어가 합법적으로 처리되어지지 못하고 야적, 방치, 불법 매립 및 소각 등의 방법으로 처리됨으로써 환경적인 오염뿐만 아니라 시각적 공해, 대기 오염 등의 문제를 심각하게 야기 시키고 있다.(중략)

• Journal of the Korea Organic Resources Recycling Association
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• v.28 no.1
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• pp.37-51
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• 2020

Following the Paris Agreement adopted at the end of 2015, global stock-taking has been planned to be carried out on a 5-year basis from 2023, and it is mandatory to report on national GHG inventory and progress toward achieving greenhouse gas reduction targets. To prepare for this, it is important to improve the reliability of estimation of the greenhouse gas emission, identify the characteristics of each greenhouse gas emission source, and manage the amount of emissions. As such, this study compared and analyzed the amount of emissions from the landfill sector using the 2000 GPG, the 2006 IPCC Guidelines, and the 2019 Refinement estimation method. As a result, in comparison to 2016, there were 2,287 Gg CO₂_eq. in scenario 1, 1,870 Gg CO₂_eq. in scenario 2-1, 10,886 Gg CO₂_eq. in scenario 2-2, 10,629 Gg CO₂_eq. in scenario 2-3, and 12,468 Gg CO₂_eq. in scenario 3. Thus, when the 2006 IPCC Guidelines were applied with respect to 2000 GPG, it was revealed that greenhouse gas emissions have increased. Such difference in the emission changes was due to the changes in the calculation method and the emission factor values applied. Therefore, it is urgent to develop national-specific values of the emission factor based on characteristics of greenhouse gas emission in Korea.