• Clean Technology
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• v.24 no.3
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• pp.221-232
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• 2018

This research was conducted to evaluate the operational performance of landfill facility and landfill gas energy facility from the questionnaire survey. In order to evaluate overall operational performance, three types of weighting methods were applied to each technical, economical, and environmental item. There was no significant difference between an equal weighted method, a weighted method of 40% for technology, 30% for economy, and 30% for environment, and a weighted method of 30% for technology, 40% for economy, and 30% for environment. In technical performance, large and middle scales of landfill facilities showed higher scores of 14.8 ~ 19.7 and 14.3 ~ 19.0 than 9.8 ~ 13.0 of small scale one. In environmental performance, large, middle, and small scales of landfill facilities showed 21.3 ~ 23.7, 17.6 ~ 19.6, and 20.8 ~ 23.1 scores, respectively. However, in economical performance, there was significant difference between them with scale. Large and middle scales of landfill facilities showed higher scores of 22.0 ~ 29.3 and 20.5 ~ 27.3 than 6.0 ~ 8.0 of small scale one. As a result of evaluation for landfill gas energy facility, large scale facility showed 19.2 ~ 25.6 and 17.8 ~ 23.7 scores in technical performance and 23.1 ~ 25.7 and 21.3 ~ 23.7 scores in environmental performance, respectively. However, in economical performance evaluation, large scale of landfill gas energy facility showed relatively higher of 27.8 ~ 33.3 score than 18.8 ~ 25.1 of small scale one. From these results, it was shown that economy evaluation heavily effect on the operational performance of landfill facility and landfill gas energy facility compared to technology and environment evaluation.

• Applied Chemistry for Engineering
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• v.18 no.6
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• pp.612-617
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• 2007

This research was performed to evaluate the effect of 'Food Wastes (FW) Direct Landfilling Prohibition' on characteristics of landfill gas (LFG) and leachate and the appropriateness of current legislation. Approximately 45% (Exp.45) and 15% (Exp.15) of FW were filled in two lysimeters. During 570 days, 1400 L of LFG was generated from Exp.45%, which was much more than 906 L of Exp.15. There was no significant difference of LFG composition between Exp.15 and Exp.45. 2~30 ppmv of odorous hydrogen sulfide was detected in Exp.45, while 2~7 ppmv was in Exp.15. There was also no significant difference in the leachate generation between the two. On day 570, $BOD_5$ of Exp.45 and Exp.15 were 37000 mg/Land 25630 mg/L and $COD_{Cr}$ of Exp.45 and Exp.15 were 45480 mg/L, 30294 mg/L. TOC of Exp.45 was 2~3 times higher than Exp.15. Higher portion of FW in landfilling increased LFG generation. However, it generated more odor and made the quality of leachate. Therefore, 'FW direct Landfilling Prohibition' was evaluated as an appropriate legislation.

• Journal of Environmental Policy
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• v.5 no.2
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• pp.69-93
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• 2006

This paper considers major three steps to arrive at accurate baseline emissions against which actual emission reductions attributable to CDM projects are accounted for. The first step is to select most likely baseline scenario among plausible alternatives. Then, the additionality of the project in question would be assessed by demonstrating that the project is not included in the baseline scenario selected. Finally, baseline emissions are calculated under the baseline scenario. In this paper, these three steps are integrated into a single flow chart in order to help understand the procedures for application of a baseline methodology better. Following the flow chart, a landfill gas-to-electricity project in Korea is analyzed as a case study. In consequence, this paper concludes that landfill gas-to-electricity projects in Korea have great potential for CDM projects, and it could also be concluded that data availability and reliability are a prerequisite for successful application of baseline methodologies for landfill gas projects to Korean specific situations.

• Economic and Environmental Geology
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• v.29 no.3
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• pp.325-333
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• 1996

numerical model is developed to estimate gas flow in the landfill site. Darcy's law, the mass conservation law, and the ideal gas state equation are combined to compose the governing equation for the steady-state and transient-state gas flows. The finite element method (FEM) is used as the numerical solution scheme. Two-dimensional radial symmetric triangular ring element is used to discretize the simulation domain. The steady state model developed in this study is compared with AIRFLOW that is a commercial model developed by Hydrologic Inc. Mass balance test is performed on the transient gas flow simulation. The developed model is applied to analyze the gas extraction experiment performed by Daewoo Institute of Construction Technology at the Nanjido landfill in 1993. The developed model was registered at Korea Computer Program Protection Foundation.

• Journal of the KSME
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• v.31 no.9
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• pp.812-819
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• 1991

고분자 폐기물을 처리하는 방법은 크게 재이용, 소각, 매립 등으로 나눌 수 있으나 재이용이나 매립 방법은 폐기물의 급속한 증가를 감당하기에 한계가 있다. 소각은 폐기물의 감량화와 폐열 회수의 이중 효과를 얻을 수 있는 가장 일반적이고 손쉬운 방법이긴 하지만 폐고무나 폐합성 수지와 같은 고분자폐기물을 직접 소각할 때에는 많은 유해가스, 분진과 매연이 발생하는 어려 움이 따른다. 건류소각 방식은 이러한 직접 소각의 단점을 보완해 주는 것으로 최근 각광을 받고 있으나 안전성, 유지관리 및 시설비 등의 면에서 뿐만 아니라 기술적인 면에서도 아직 많은 연 구가 요구되고 있다. 열분해 또는 건류 가스화에 관한 연구는 석탄에 대하여 활발하게 이루어져 왔으며 1960년대에는 심각한 환경오염을 겪으면서 폐기물 처리에 대한 응용이 시작되었다. 1970년대부터 미국에서는 EPA(environmental protection agency)의 주도로 도시쓰레기에서 가스, 기름 등을 회수하는 기술개발을 강력히 추진하였으며 일본에서도 통상산업성 산하 공업기술원의 도시쓰레기 열분해 처리 기술 개발을 시작으로 2차공해 감소를 선결 과제로 한 여러 가지 프로 세스를 개발해 왔다. 국내에서는 최근에들어 연구가 비교적 활발하게 이루어 지고 있다. 특히 동력자원부 주관의 대체에너지 사업의 일환으로 추진중인 폐기물의 에너지화 이용에 관한 연구 중에서도 열분해나 건류 가스화에 관련된 연구가 많은 비중을 차지하고 있다.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.13 no.1
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• pp.221-232
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• 1993

In this study, the period for stabilization in the case of recycling leachate was compared and analyzed with the case of non-cycle type, using lysimeters filled with municipal organic refuse. The lysimeters were operated with various detention time. In addition, the degree of stabilization was estimated by the way of measuring the quantity of gas from landfills. As the results, the recycle of leachate, which was modified as the neutral level of pH, accelerated the biological decomposition of organics with the raped growth of anaerobic bacteria in the system, and reduced the period for the stabilization. In the case of BOD and COD in leachate, COD. which had been originality similar to BOD, had increased more rapidly than BOD as time lapsed. Moreover, the quantity of gas from the recycle reactor was larger than from the non-cycle reactor. The shorter the detention time of leachate gas, the larger the quantity of gas produced in the lysimeters.

• Journal of the Korean Society of Groundwater Environment
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• v.3 no.2
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• pp.80-94
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• 1996

The Nanjido Landfill has recently become one of the most important environmental sites for a hydrogeological study. Hydrogeological study was performed by understanding the current situation, analyzing hydrogeological information, and constructing a hydrogeological data base. The constructed data base was used for the analyses of several important phenomena in the Nanjido Landfill. Saturated hydraulic conductivity and underground temperature were measured. Based on the hydraulic conductivity and rainfall data, net infiltration rates were estimated. Leachate production rates are estimated by using the data base. The data base and a hydraulic model were used to understand the formation of the so called floating leachate layer.

• Proceedings of the Korean Fiber Society Conference
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• 2003.04a
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• pp.235-238
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• 2003

폐기물 매립시스템은 크게 폐기물의 토양으로의 유출에 의한 오염방지를 위한 lining system과 폐기물에서 발생하는 가스의 방출차단과 빗물의 매립시스템으로의 침투방지를 위한 covering system으로 나뉘어진다. Lining system은 폐기물 하부에 차수층, 침출수 배수층, 침출수 차단층과 차수재 보호층 순으로 구성되며, covering system은 폐기물 상부에 집수관을 설치한 후 중간 복토층을 둔 후, 가스 차단층, 봉합층, 배수장치와 보호층 순으로 구성되어진다. (중략)

• Journal of the Korean GEO-environmental Society
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• v.15 no.5
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• pp.5-11
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• 2014

In this study, greenhouse gas emission for small scale landfill (H and Y landfill) was investigated to deduce special the methane generation rate constant(k). To achieve the purpose, the data of physical composition was collected and amount of LFG emission was calculated by using FOD method suggested in 2006 IPCC GL. Also, amount of LFG emission was directly measured in the active landfill sites. By comparing the results, the methane generation rate constant(k), which was used as input variable in FOD method suggested in 2006 IPCC GL, was deduced. From the results on the physical composition, it was shown that the ranges of DOC per year in H (1997~2011) and Y (1994~2011) landfill sites were 13.16 %~23.79 % ($16.52{\pm}3.84%$) and 7.24 %~34.67 % ($14.56{\pm}7.30%$), respectively. The DOC results showed the differences with the suggested values (= 18 %) in 2006 IPCC GL. The average values of methane generation rate constant(k) from each landfill site were $0.0413yr^{-1}$ and $0.0117yr^{-1}$. The results of methane generation rate constant(k) was shown big difference with 2006 IPCC GL defualt value (k = 0.09). It was confirmed that calculation results of greenhouse gas emission using default value in 2006 IPCC GL show excessive output.

• Journal of the Korean Institute of Gas
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• v.18 no.6
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• pp.21-26
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• 2014

Renewable gas fuels such as biogas and landfill gas have carbon-neutral nature which can reduce carbon dioxide. However, it is necessary to make stable combustion when this fuel is used in power generating SI(spark ignition) gas engines due to its low heating value and non-uniformity. In this study, it was shown that addition of hydrogen can increase combustion stability of gas engine which is running with high inert gas composition. Thermal efficiency and emission characteristics of this engine was also investigated. 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 exhaust emissions.