• 한국폐기물자원순환학회지
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• 제35권7호
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• pp.606-615
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• 2018

Over the past two decades, the options for solid waste management have been changing from land disposal to recycling, waste-to-energy, and incineration due to growing attention for resource and energy recovery. In addition, the reduction of greenhouse gas (GHG) emission has become an issue of concern in the waste sector because such gases often released into the atmosphere during the waste management processes (e.g., biodegradation in landfills and combustion by incineration) can contribute to climate change. In this study, the emission and reduction rates of GHGs by the municipal solid waste (MSW) management options in D city have been studied for the years 1996-2016. The emissions and reduction rates were calculated according to the Intergovernmental Panel on Climate Change guidelines and the EU Prognos method, respectively. A dramatic decrease in the waste landfilled was observed between 1996 and 2004, after which its amount has been relatively constant. Waste recycling and incineration have been increased over the decades, leading to a peak in the GHG emissions from landfills of approximately $63,323tCO_2\;eq/yr$ in 2005, while the lowest value of $35,962tCO_2\;eq/yr$ was observed in 2016. In 2016, the estimated emission rate of GHGs from incineration was $59,199tCO_2\;eq/yr$. The reduction rate by material recycling was the highest ($-164,487tCO_2\;eq/yr$) in 2016, followed by the rates by heat recovery with incineration ($-59,242tCO_2\;eq/yr$) and landfill gas recovery ($-23,922tCO_2\;eq/yr$). Moreover, the cumulative GHG reduction rate between 1996 and 2016 was $-3.46MtCO_2\;eq$, implying a very positive impact on future $CO_2$ reduction achieved by waste recycling as well as heat recovery of incineration and landfill gas recovery. This study clearly demonstrates that improved MSW management systems are positive for GHGs reduction and energy savings. These results could help the waste management decision-makers supporting the MSW recycling and energy recovery policies as well as the climate change mitigation efforts at local government level.

• 자원리싸이클링
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• 제12권5호
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• pp.42-49
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• 2003

넓은 입도분포를 가지는 헤마타이트 철광석을 사용하여 $H_2$ 및 $H_2$-CO 혼합가스 분위기에서 환원 및 탄회특성에 대하여 고찰하였다. 환원에 의한 활성화에너지 값은 약 20kJ/mol 였다. 환원 및 탄화단계에서 무게변화는 환원단계에서는 약 28% 감소하였고, 탄화단계에서는 약 5%증가하였다. 이는 이론 계산식에 의한 값과 거의 일치하였다. 온도, 입도 및 가스비($_H2$/CO=1～5 범위)에 따른 탄화속도는 온도가 낮을수록 입자가 작을수록 그리고 가스비가 작을수록 탄화속도가 증가하였다. 또한 $H_2$의 가스비($H_2$/CO=1)가 낮을 때는 유리카본(C, free carbon)이 발생하였다. 수소가스를 혼합하였을 경우가 탄화속도는 증가하였으나, 수소분율에 비례하여 증가하지는 않았다. 혼합가스 중 수소분율($X_{H2}$ )이 0.5일 때 ($H_2$/CO=1) 탄화속도가 최대였다. 이때 수소가 탄화철 생성과정에 있어서 촉매역할을 한 것으로 추정된다.

• 한국수소및신에너지학회논문집
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• 제20권2호
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• pp.151-160
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• 2009

Natural gas combustion characteristics of mass produced oxygen carrier particles were investigated in a batch type bubbling fluidized bed reactor. Five particles, NiO/bentonite, OCN601-650, OCN702-1100, OCN703-950, OCN703-1100 were used as oxygen carrier particles. Natural gas and air were used as reactants for reduction and oxidation, respectively. During reduction reaction, high fuel conversion and high $CO_2$ selectivity were achieved for most of oxygen carriers. During oxidation, NO emission was very low. These results indicate that inherent $CO_2$ separation and low NOx combustion are feasible for the natural gas fueled chemical-looping combustion system. Among the five oxygen carriers, OCN703-1100 particle was selected as the best candidate for demonstration of long-term operation in large-scale chemical-looping combustor from the viewpoints of fuel conversion, $CO_2$ selectivity, $CH_4$ concentration, and CO concentration.

• 한국해양환경ㆍ에너지학회지
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• 제6권3호
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• pp.16-25
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• 2003

본 논문에서는 RORO선을 이용한 연안운송에 따른 CO₂가스 배출량과 NOx가스 배출량의 삭감 효과에 대하여 고찰한다. 먼저 국내 CO₂가스 배출량과 수출입 컨테이너화물의 물동량에 대하여 고찰한다. 다음에 RORO선의 특성, CO₂가스 배출량 기준과 NOx가스 배출량 기준에 대하여 고찰한다. 또한 경인지역과 부산항 사이의 수출입 컨테이너 화물의 운송에 있어서 도로운송을 연안운송으로 전환한 경우의 CO₂가스 배출량과 NOx가스 배출량 삭감 효과에 대하여 계산한다. 마지막으로 RORO선의 적재율과 연안운송 분담율 변화에 따른 CO₂가스 배출량과 NOx가스 배출량 변화에 대하여 조사한다. 본 논문의 결과를 통하여 수출입컨테이너 화물의 운송을 도로운송으로부터 RORO선을 이용한 연안운송으로 전환하는 것이 CO₂가스 배출량 삭감에는 효과적이나 NOx가스 배출량 삭감에는 큰 효과가 없는 것을 확인하였다.

• 한국기후변화학회지
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• 제9권3호
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• pp.245-251
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• 2018

Creating Shared Value (CSV) is a new business paradigm in which enterprises benefit from social works. The goal of this study is to assess greenhouse gas emission reduction through CSV-related activities of Yuhan-Kimberly (YK) Company. YK Company has planted over 50 million trees between 1984 and 2016 as a part of CSV activities. Through planting of trees, annual $CO_2 $ emission reduction ranged from 196.2 thousand to $336.3\;thousand\;tCO_2-eq$ depending on forest type in 2016, representing 44 million to 84 million KRW. Those results indicate that the company can contribute to reduction of greenhouse gas emissions as well as obtain economic profits through CSV-related activities. Furthermore, this study provides motives for other companies interested in similar CSV projects.

• Journal of Welding and Joining
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• 제12권1호
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• pp.51-58
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• 1994

Amount of spatter, welding conditions and welding costs were investigated for MAG welding. $CO_2$, Ar+18%;$CO_2$ and Ar+8%$O_2$ were used for shielding gases. As results, arc characteristics and appropriate range for welding were obtained. Amount of spatter in Ar+18%$CO_2$ gas welding was 20% of that of $CO_2$ welding, and Ar+8%$O_2$ was 10% of that of $CO_2$ welding. Therefore by using Ar+18%$CO_2$and Ar+8%$O_2$ gases, welding costs could be reduced compared with $CO_2$ welding due to avoiding spatter.

• 한국대기환경학회지
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• 제32권3호
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• pp.280-288
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• 2016

Greenhouse gas (GHG) emissions have given rise to climate change which is one of the most serious environmental challenges that the world faces today. In response, Republic of Korea has proposed "Low Carbon, Green Growth" as a new economic paradigm accompanying with the ultimate aim of building a sense of responsibility for the environment. Korean government has set the ambitious national GHG emission reduction target which aims 37% reduction in the business-as-usual (BAU) level of 2030. The transportation sector plays a key role in this target. In the transportation sector, the GHG reduction target of 34.3% in the BAU level by 2020 has been allocated in order to consider the industrial specificity. Furthermore, it is known that the GHG reduction in the transportation sector has relatively minimal side effects compared to those of other sectors. In order to meet this national GHG reduction target, Korean government has set $CO_2$ emission regulation of vehicle for 2020. The purpose of this study is to evaluate the reduction effects by the average GHG regulation of vehicles. $CO_2$ emissions, between 2009 and 2013 were analysed by reduction measure such as technology improvement, light-weight, segment shift, diesel vehicle sales. During this period, $CO_2$ of vehicle was reduced every year by 19.9 g/km (i.e., 3.3% reduction per year). $CO_2$ reduction of imported vehicle is greater than domestic vehicle because of segment shift toward small size vehicle and higher diesel vehicle sales.

• 한국자동차공학회논문집
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• 제20권4호
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• pp.142-149
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• 2012

The reduction characteristics of $NO_2$ to NO are experimentally studied over a platinum-based catalyst, especially at lower temperatures below about $200^{\circ}C$. In the present work, two types of steady-state experiments, engine bench and synthetic gas bench tests, are carried out in sequence. Steady-state engine bench tests with the DOC mounted on a light duty 4-cylinder 2.0 liter turbocharged diesel engine are performed and prove that CO plays a major role in $NO_2$ abatement at temperatures below the light-off temperature of CO oxidation, about $200^{\circ}C$. Synthetic gas bench tests are then performed using synthetic gas mixtures with CO, $C_3H_6$, NO, $NO_2$, $O_2$, $H_2O$ and $N_2$ in the $140{\sim}450^{\circ}C$ T-range and show that both CO and $C_3H_6$ are capable of reducing $NO_2$. It is noted that the reaction rate of $NO_2$ with $C_3H_6$ is much higher than that with CO. At temperatures below about $200^{\circ}C$, the reduction of $NO_2$ to NO is promoted with increasing CO concentration and $NO_2$/$NO_X$ ratio and with decreasing $O_2$ concentration, as well as with the presence of $H_2O$.

• 자원리싸이클링
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• 제22권6호
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• pp.3-11
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• 2013

본 연구는 사용종료매립지 정비를 위한 폐기물 처리과정에서 가연성폐기물의 처리 방법별 온실가스 발생량을 IPCC에서 제시하고 있는 기본배출계수(default emission factor)를 활용하여 산정하고 그 결과 비교를 통해 온실가스 감축량을 산정하였다. 대상 매립지로부터 굴착한 폐기물의 성상을 조사한 결과 토사류가 64.96%로 가장 많은 비율을 차지하고 있었으며, 다음으로 비닐/플라스틱류가 19.18%의 비율을 차지하고 있어 전체 폐기물 중 토사류의 비율이 매우 높은 것으로 나타났다. 음식물류, 목초류, 종이류와 같이 생분해가 용이한 폐기물이 거의 발견되지 않은 점 등이 일반적인 비위생매립지의 굴착폐기물과 성상이 유사하였다. 전체 폐기물의 겉보기 밀도는 평균 $0.74t/m^3$으로 확인되었다. 폐기물을 매립으로 처리하는 경우 약 60,542 $tCO_2$, 소각을 통해 폐기물 처리 시 9,933 $tCO_2$의 온실가스가 배출되며 폐기물 고형연료 생산 시에는 33,738 $tCO_2$의 온실가스가 감축되는 것으로 산정되어 폐기물 고형연료 생산이 온실가스 감축에 도움이 되는 것으로 확인되었다.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2009년도 춘계학술대회 논문집
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• pp.821-824
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• 2009

LFG-MGT CHP system development project with $CO_2$ enrichment in greenhouses was introduced. LFG is produced from the anaerobic digestion of landfilled waste and it has been utilized for power/heat generation since it contains around 50% of $CH_4$. Utilization of LFG from small scale landfill is also needed as well as large scale landfill. However, due to economy of scale, it is very difficult to develop business model. In this context, combining CHP system with greenhouses is considered as feasible option for LFG utilization. LFG-MGT CHP system with $CO_2$ fixation in greenhouses has been derived as an active greenhouse gas reduction strategy, The focus of the system is beyond carbon neutral LFG utilization to neutral carbon absorption. The system is feasible in terms of direct and indirect $CO_2$ emission reduction with more economical way.