• Proceedings of the SAREK Conference
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• 2008.06a
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• pp.1243-1248
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• 2008

$CO_2$ emission amount and characteristics of combined heat and power (CHP) plant in industrial complex of Korea is evaluated by using the fuel analysis method. Fuel analysis methods of several foreign countries and developed one which is developed considering the operation characteristics of the surveyed CHP plants are used. The operation data is surveyed for all of the CHP plants in industrial complex and is composed of fuel consumption amount, generation, sale and efficiency of heat and electricity, condensed steam enthalpy, and etc of the each CHP.

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.411.2-411.2
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• 2016

직접 메탄올 연료전지 (DMFCs)는 친환경적이고 낮은 작동 온도로 인한 빠른 구동, 높은 에너지 밀도 등 다양한 장점을 가지고 있어 차세대 에너지 변환소자로 많은 관심을 받고 있다. 직접 메탄올 연료전지는 메탄올을 연료로 사용하며, 메탄올이 보유하고 있는 화학적 에너지를 전기 에너지로 변환하는 장치로써 음극에서는 백금 촉매로 인한 메탄올 산화반응, 양극에서는 환원 반응이 일어나며 전기화학적 구동을 하게 된다. 하지만 일산화탄소 피독으로 인한 촉매 활성 저하, 메탄올의 cross over, 백금 촉매 사용으로 인한 고비용 등의 문제점을 가지고 있다. 따라서 많은 연구자들이 백금 사용량을 줄이고 백금 촉매를 고르게 분포하기 위해 값이 저렴하고 넓은 비표면적을 갖는 탄소계 (graphite, graphene, carbon nanotube, carbon nanofiber 등) 지지체 재료를 도입하고 있다. 이 중 탄소나노섬유 (carbon nanofibers, CNFs)는 우수한 전기전도도와 열적/화학적 안정성을 가지고 있으며, 특히 넓은 비표면적을 가지고 있어 백금 촉매의 지지체로서 많은 연구가 진행되고 있다[1]. 따라서 우리는 전기방사법을 활용하여 넓은 비표면적을 보유하는 다공성 탄소나노섬유를 성공적으로 합성하였다. 또한, 이를 백금 촉매의 지지체로 도입하여 직접 메탄올 연료전지를 위한 다공성 탄소나노섬유에 담지된 고분산성 백금 촉매를 제조하였다. 제조한 다공성 탄소나노섬유의 형상 및 구조 분석은 주사전자 현미경 (field-emission scanning electron microscopy)와 투과전자 현미경 (transmission electron microscopy)를 이용하여 분석하였고, 결정구조와 화학적 결합상태는 X-선 회절분석 (X-ray diffraction) 및 X-선 광전자 분광법 (X-ray photoelectron spectroscopy)를 이용하여 규명하였다. 전기화학적 특성은 순환 전압 전류법 (cyclic voltammetry)를 이용하였다. 이러한 실험 결과들을 바탕으로 다공성 탄소나노섬유에 담지된 고분산성 백금 촉매의 자세한 특성을 본 학회에서 다루도록 하겠다.

• Journal of Korea Port Economic Association
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• v.25 no.2
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• pp.231-246
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• 2009

The time charterer depends on speed and bunker consumption rate of time chartered vessel because it is related charterers' benefit. It is important role of stipulated speed and daily bunker consumption rate at the Time Charter Party, it is generated any dispute against speed and daily bunker consumption rate deficiency. The case of dispute is a restricted word of stipulated speed and daily bunker consumption rate at Charter Party as "about", "good weather or good weather day", "smooth water", "ocean current" and "without guarantee". It happens a dispute against speed and daily bunker consumption rate because it is not well-educated as a vessel operator regarding Time Charter Party interpretation.

• 한국신재생에너지학회:학술대회논문집
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• 2011.05a
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• pp.185.2-185.2
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• 2011

1900년대 이후 산업발전에 따른 인구의 도시 집중화로 인한 하수량 증가에 따라 하수슬러지 발생량이 점차 증가하게 되면서 하수슬러지 처리에 관한 문제 등이 제기되기 시작하였다. 국내의 경우 2003년 하수슬러지의 매립이 금지된 후, 발생슬러지 대부분을 해양투기 등을 통해 처리하여왔다. 2009년 기준으로 국내에서 발생되는 하수슬러지량과 처리 분포를 살펴보면 전국 433개소 하수처리장에서 1일 평균 8,295톤(3,028천톤/년)이 발생되고 있으며, 이 중 47%가 해양투기 되고 있는 실정이다. 그러나 해양투기마저도 런던협약'96의정서 가입으로 2012년부터 금지됨에 따라 국내에서는 슬러지처리 및 재활용 방안과 관련한 연구개발이 활발히 진행되고 있는 중이다. 하수슬러지 처리 및 재활용기술의 경우 다양한 공법 등이 개발 중에 있으나 설비의 불안정 및 높은 투자비 등으로 인해 아직까지 상용화 된 설비 등은 많지 않은 실정이다. 이에 따라 본 연구에서는 POSCO 건설에서 개발한 슬러지 연료화 기술을 통해 생산된 슬러지 탄을 석탄 화력발전소 등에 석탄 보조연료로 활용할 수 있는 방안을 강구하여 상용화 가능한 혼소 기술을 개발하고자 하였다. 슬러지탄(발열량 3.000kcal 이상)을 석탄 화력발전소 보일러에 일정 비율로 혼소하여 슬러지탄의 품질평가, 중금속 용출시험 및 함량분석, 잔재물의 중금속 용출시험 등을 실시하였으며, 그 결과 모든 시험항목에서 연료화 관련 법적기준을 만족하는 것으로 나타났다. 슬러지탄을 화력발전소에 혼소하여 사용할 경우, 2012년부터 시행예정인 RPS(Renewable Portfolio Standard)법 대응 및 석탄사용량 저감 등을 통한 $CO_2$ 저감으로 저탄소 녹색성장의 자원순환사회를 구축하는 데 이바지 할 것으로 판단된다.

• Resources Recycling
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• v.6 no.2
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• pp.70-77
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• 1997

The paper revlcws [he kinds and thcir physical and chemical characleristics of varlnus plastics. The nccds for ~ccycling of used plastics are emphasized and problems and challcngcs ilssoclatcd with treatments of such used plastics are described It aLra makes various suggestions to meet and solve these problems.

• Journal of Energy Engineering
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• v.24 no.4
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• pp.81-88
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• 2015

In midst of electrical energy consumption on the rise due to the industrial development and the improved quality of living, medium capacity and multi boilers which use gas that is comparatively low cost and can be supplied reliably are simulated for energy consumption using the partial load data obtained from the experiment. Economic analysis that considers initial and operation costs is carried out based on the Annual equal payment method.

• Proceedings of the KOR-BRONCHOESO Conference
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• 1972.03a
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• pp.5-6
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• 1972

Noise and air pollution, which accompany the development of industry and the increase of population, contribute to the deterioration of urban environment. The air pollution level of Seoul has gradually increased and the city residents are suffering from a high pollution of noise. If no measures were taken against pollution, the amount of emission of pollutant into air would be 36.7 thousand tons per year per square kilometer in 1975, three times more than that of 1970, and it would be the same level as that of United States in 1968. The main sources of air pollution in Seoul are the exhaust has from vehicles and the combustion of bunker-C oil for heating purpose. Thus, it is urgent that an exhaust gas cleaner should be instaled to every car and the fuel substituted by less sulfur-contained-oil to prevent the pollution. Transportation noise (vehicular noise and train noise) is the main component of urban noise problem. The average noise level in downtown area is about 75㏈ with maximum of 85㏈ and the vehicular homing was checked 100㏈ up and down. Therefore, the reduction of the number of bus-stop the strict regulation of homing in downtown area and a better maintenance of car should be an effective measures against noise pollution in urban areas. Within the distance of 200 metres from railroad, the train noise exceeds the limit specified by the pollution control law in Korea. Especially, the level of noise and steam-whistle of train as measured by the ISO evaluation can adversely affect the community activities of residents. To prevent environmental destruction, many developed countries have taken more positive action against worsening pollution and such an action is now urgently required in this country.

• Korean Journal of Soil Science and Fertilizer
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• v.46 no.6
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• pp.502-509
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• 2013

To estimate greenhouse gas (GHG) emission, we established inventory of conventional rice cultivation from farmers in Gunsan and Iksan, Jeonbuk province in 2011~2012. This study was to calculate carbon footprint and to analyse the major factor of GHGs. We carried out a sensitivity analysis using the analyzed main factors of GHGs and estimated the mitigation potential of GHGs. Also we tried to suggest agricultural methods to reduce GHGs that farmers of this case study can apply. Carbon footprint of rice production unit of 1 kg was 2.21 kg $CO_2.-eq.kg^{-1}$. Although amount of $CO_2$ emissions is largest among GHGs, methane had the highest contribution of carbon footprint on rice production system after methane was converted to carbon dioxide equivalent ($CO_2$-eq.) multiplied by the global warming potential (GWP). Source of $CO_2$ in the cultivation of rice farming is incomplete combustion of fossil fuels used by agricultural machinery. Most of the $CH_4$ emitted during rice cultivation and major factor of $CH_4$ emission is flooded paddy field in anaerobic condition. Most of the $N_2O$ emitted from rice cultivation process and major sources of $N_2O$ emission is application of fertilizer such as compound fertilizer, urea, orgainc fertilizer, etc. As a result of sensitivity analysis due to the variation in energy consumption, diesel had the highest sensitivity among the energies inputs. If diesel consumption is reduced by 10%, it could be estimated that $CO_2$ potential reduction is about 2.5%. When application rate of compound fertilizer reduces by 10%, the potential reduction is calculated to be approximately 1% for $CO_2$ and approximately 1.8% for $N_2O$. When drainage duration is decreased until 10 days, methane emissions is reduced by approximately 4.5%. That is to say drainage days, tillage, and reducing diesel consumption were the main sources having the largest effect of GHG reduction due to changing amount of inputs. Accordingly, proposed methods to decrease GHG emissions were no-tillage, midsummer drainage, etc.

• Journal of the Korean Institute of Gas
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• v.27 no.3
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• pp.77-83
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• 2023

Energy consumption is increased by rapid industrialization. As a result, climate change is accelerating due to the increase in CO₂ concentration in the atmosphere. Therefore, a shift in the energy paradigm is required. Hydrogen is in the spotlight as a part of that. Currently 95% of hydrogen is fossil fuel-based reforming hydrogen which is accompanied by CO₂ emissions. This is called gray hydrogen, if the CO₂ is captured and emission of CO₂ is reduced, it can be converted into blue hydrogen. There are 3 technologies to capture CO₂: absorption, adsorption and membrane technology. In order to select CO₂ capture technology, the analysis of the exhaust gas should be carried out. The concentration of CO₂ in the flue gas from the hydrogen production process is higher than 20%if water is removed as well as the emission scale is classified as small and medium. So, the application of the membrane technology is more advantageous than the absorption. In addition, if LNG cold energy can be used for low temperature CO₂ capture system, the CO₂/N₂ selectivity of the membrane is higher than room temperature CO₂ capture and enabling an efficient CO₂ capture process. In this study, we will analyze the flue gas from hydrogen production process and discuss suitable CO₂ capture technology for it.

• Environmental and Resource Economics Review
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• v.30 no.4
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• pp.627-648
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• 2021

The fine-dust season management system refers to the policy of implementing enhanced reduction measures in transportation, power, business and living sectors in winter, when fine dust levels are high. The fine dust season management system is a regulatory policy that causes social costs and transfers to various economic players. Equity is an important issue for the cost burden. Therefore, in this study, the cost of each power generator was analyzed using the coal power generation reduction amount of each power generator to verify that the cost of the power sector is evenly distributed. In particular, the effect of the fine dust season management system on coal power generation of power generators was analyzed by applying a synthetic control method that can identify the time-variable effect of the policy. It was confirmed that the fine dust season management system reduced volume of fuel and power generation in coal power plants, resulting in an increase in the cost of the power generation sector, even considering the effect of some power demand due to the COVID-19 crisis. However, it could be seen that these costs were not distributed equally among the generators, and that they were more costly to the specific generators.Social costs incurred by fine dust season management need to be improved so that stakeholders are equally burdened.