• 전기학회논문지
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• 제58권3호
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• pp.467-477
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• 2009

Renewable Portfolio Standard (RPS) is a regulatory policy that requires the generation companies to increase the proportion of renewable energy sources such as wind, solar, LFG, fuel cell, and small hydro. Recently, Korean government decided to increase the portion of renewable energy to 3% to total electricity generation by 2012 from the current level of 0.13%. To achieve this goal, an innovative plan for market competitiveness would be required in addition to the present Feed-In-Tariff (FIT). That is Korean government has taken it into consideration to introduce a Renewable Portfolio Standard (RPS) as an alternative to FIT. This paper reviews the impact of RPS on the long-term fuel mix in 2020. The studies have been carried out with the GATE-PRO (Generation And Transmission Expansion PROgram) program, a mixed-integer non-linear program developed by Hongik university and Korea Energy Economics Institute. Detailed studies on long-term fuel mix in Korea have been carried out with four RPS scenarios of 3%, 5%, 10% and 20%. The important findings and comments on the results are given to provide an insight on future regulatory policies.

• 한국연소학회지
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• 제13권3호
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• pp.1-8
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• 2008

A flame stability diagram in a partially premixed flame is typically expressed using the axis coordinates of heat input rate and equivalence ratio. These diagrams are inadequate for identifying changes in combustion conditions and flame stability when a reference fuel is substituted with other fuels under identical operating conditions. This study proposes a new type of diagram and validates it experimentally. In this new diagram, the axis coordinates are air flow rate and Wobbe fuel flow rate, defined as the fuel flow rate multiplied by the square root of the relative density. The diagram was validated in trials using various fuels, including $CH_4$, $C_{3}H_{8}$, and LFG-$C_{3}H_{8}$ mixed fuels, in a domestic gas-range and an gas interchangeability test burner. The results of these trials show that the new diagram can provide information useful for assessing gas interchangeability of combustion conditions and flame stability when one fuel is substituted with another under identical operating conditions.

• 한국자원공학회지
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• 제55권6호
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• pp.649-659
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• 2018

본 연구는 매립장 매립가스 발전소를 대상으로 발전소 운영 데이터들을 수집 후, 딥러닝(Deep Learning) 기법을 적용하여 향후 메탄가스 농도를 예측하였다. 2017년 1월부터 11월까지 88일치에 대해서 23개 포집공에서 메탄가스 농도, 이산화탄소 농도, 황화수소 농도, 산소 농도, 밸브 개방정도, 기온, 습도 데이터를 수집하였다. 수집 데이터로 딥러닝 모델을 학습한 후 실제 데이터와 비교하였다. 추정 결과 23개 포집공 모두에서 매우 정확한 추정결과를 보였다.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2010년도 춘계학술대회 초록집
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• pp.244.1-244.1
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• 2010

Bio energy development by using Low Calorific Gas Turbine(LCGT) has been developed for New & Renewable energy source for next generation power system, low fuel and operating cost method by using the renewable energy source in landfill gas (LFG), Food Waste, water waste and Livestock biogas. Low calorific fuel purification by pretreatment system and carbon dioxide fixation by green house system are very important design target for evaluate optimum applications for bio energy. Main problems and accidents of Low Calorific Gas Turbine system was derived from bio fuel condition such as hydro sulfide concentration, siloxane level, moisture concentration and so on. Even if the quality of the bio fuel is not better than natural gas, LCGT system has the various fuel range and environmental friendly power system. The mechanical characterisitics of LCGT system is a high total efficiency (>70%), wide range of output power (30kW - 30MW class) and very clean emmission from power system (low NOx). Also, we can use co-generation system. A green house designed for four different carbon dioxide concentration from ambient air to 2000 ppm by utilizing the exhaust gas and hot water from LCGT system. We look forward to contribute the policy for Renewable Portfolio Standards(RPS) by using LCGT power system.

• 유기물자원화
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• 제13권1호
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• pp.124-130
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• 2005

매립은 폐기물의 최종처분방법으로 광범위하게 이용되며, 매립된 폐기물은 미생물의 활동에 의해 분해된다. 미생물에 의한 생분해는 수분함량, 산화환원전위, pH, Alkalinity, 황산염, 영양물질과 미량원소, 방해인자, 미량이온, 온도와 같은 여러 인자에 의해 영향을 받는다. 특히, 수분은 미생물의 활성에 주요한 인자이다. 본 연구에서는 수분이 고형폐기물(MSW)의 분해에 미치는 영향을 조사하여 분석하였다. 이를 위해 총 8기의 모의매립조에 고형폐기물을 충전하였고, 수분함량을 20, 30, 40, 50% 4개로 하여 운전하였다. 그 결과 수분함량이 높을수록 $CO_2$의 농도가 높았고, 매립가스 또한 많이 발생 하였다. 이는 수분함량이 높을수록 미생물 분해가 효과적임을 의미한다.

• 유기물자원화
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• 제26권2호
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• pp.19-32
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• 2018

본 연구는 침출수 재순환에 의한 매립가스에 대한 메탄가스 농도에 어떠한 영향이 있는지 분석하였다. 실험대상 매립장 지역의 2010~2016년간 월평균 총강수량은 130.9mm, 2017년 6월 총강수량 73.7mm 이었다. 이러한 기상청 자료를 근거로 실험대상 매립장의 수분함수율은 낮을 것으로 예상되었다. 실험대상 매립장에 10개의 포집공을 선정하여 5톤의 침출수를 나누어서 투입하면서 매립가스 변화특성을 조사하였다. 침출수 투입하기 전 10개의 메탄가스 농도(평균) 투입전 30.14%, 투입후 메탄가스 농도(평균) 24.66%(6월 21일), 31.51%(6월 24일), 36.68%(7월 1일), 52.47%(7월 25일)로 메탄가스 농도가 증가하였다. 본 실험대상 매립장의 경우 5톤의 침출수를 투입한 결과 매립지의 유기물질 분해에 필요한 최적 함수율 50~65% 범위를 유지하는 것으로 판단된다.

• 한국환경과학회지
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• 제25권2호
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• pp.239-246
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• 2016

This study aims to analyze region-specific trends in changing greenhouse gas emissions in incineration plants of local government where waste heat generated during incineration are reused for the recent five years (2009 to 2013). The greenhouse gas generated from the incineration plants is largely $CO_2$ with a small amount of $CH_4$ and $N_2O$. Most of the incineration plants operated by local government produce steam with waste heat generated from incineration to produce electricity or reuse it for hot water/heating and resident convenience. And steam in some industrial complexes is supplied to companies who require it for obtaining resources for local government or incineration plants. All incineration plants, research targets of this study, are using LNG or diesel fuel as auxiliary fuel for incinerating wastes and some of the facilities are using LFG(Landfill Gas). The calculation of greenhouse gas generated during waste incineration was according to the Local Government's Greenhouse Emissions Calculation Guideline. As a result of calculation, the total amount of greenhouse gas released from all incineration plants for five years was about $3,174,000tCO_2eq$. To look at it by year, the biggest amount was about $877,000tCO_2eq$ in 2013. To look at it by region, Gyeonggido showed the biggest amount (about $163,000tCO_2eq$ annually) and the greenhouse gas emissions per capita was the highest in Ulsan Metropolitan City(about $154kCO_2eq$ annually). As a result of greenhouse gas emissions calculation, some incineration plants showed more emissions by heat recovery than by incineration, which rather reduced the total amount of greenhouse gas emissions. For more accurate calculation of greenhouse gas emissions in the future, input data management system needs to be improved.

• 신재생에너지
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• 제7권3호
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• pp.67-73
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• 2011

MGT fuelled by landfill gas was tested to asses feasibility of its exhaust gas application for $CO_2$ enrichment. The exhaust gas was analyzed during start-up and normal operation with different MGT load conditions. Due to the changes of air/fuel ratio and combustion mode, $O_2$, $CO_2$, CO and NOx concentration were varied within wide ranges during the MGT start-up. Especially, NOx emissioin level was increased up to 20.01 ppmv. Different tendencies of $O_2$, $CO_2$, CO and NOx concentrations were observed with MGT output changes. $O_2$ and CO concentrations were shown to be decreased and NOx and $CO_2$ concentrations were shown to have opposite trends. NOx emission level (0.8~1.88 ppmv) was very low compared to other types of combustion based power generation equipment. Unburned hydrocarbon emission level was substantially decreased with MGT load increase. Especially, $C_2H_4$ concentration was below the detection limit(0.2 ppmv) around the nominal load condition. The exhaust gas from landfill gas fuelled MGT system was shown to be feasible for $CO_2$ fertilization. Concentrations of major components were within or below the maximum allowable ranges.

• 한국토양환경학회지
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• 제3권3호
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• pp.75-86
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• 1998

쓰레기매립장에서 복토층을 통하여 대기중에 유출하는 가스를 현장에서 단시간내에 측정이 가능한 밀폐형 chamber법을 제시하였다. 또한, 최종복토층에서의 유출가스 실측치를 모델해석으로 모사하여 다음의 결과를 얻었다. 1) 시간변화에 따른 chamber내(H=10-30 cm)의 농도 변화는 30분이내로, G.C의 분석시간을 고려하여 5분단위로 분석한다. 2)메탄산화 반응의 영향으로 $CH_4$/$CO_2$비가 복토층 표면근처에서 급격히 변화한다. 3)매립지 표면의 flux가 F =$10^{-5}$mol/($m^2$.s)일 경우에는 메탄산화반응에 의해 가스조성에의 영향이 있으나, F =$10^{-6}$moll($\textrm{m}^2$.s)의 경우에는 복토층내의 메탄가스 농도가 상대적으로 적으므로 메탄산화반응에의 영향이 적다.

• 유기물자원화
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• 제8권4호
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• pp.121-128
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• 2000

본 연구에서는 매립 폐기물 분해와 사전안정화를 위한 최적 산소 전달 방식을 평가하기 위하여 대상 매립지와 모형매립조 실험을 수행하였다. 매립년한이 오래된 매립지의 경우 낮은 유기물 함량으로 인해 저압/저유량의 연속 공기 주입방식이 효과적인 것으로 나타났다. 또한, 공기 주입 및 매립가스 추출은 유기물의 생분해 보다 매립지 내부의 공기 치환에 의한 SVE (Soil Vapor Extraction)효과가 보다 큰 것으로 나타났다. 따라서, 매립지의 공기주입 방식은 매립지의 조기안정화뿐만 아니라 매립지 굴착, 선별 및 이송시 발생될 수 있는 가스 문제를 사전에 저감할 수 있을 것으로 판단된다.