• Bulletin of the Korean Chemical Society
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• 제29권7호
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• pp.1344-1348
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• 2008

A microbial fuel cell (MFC) has been regarded as noble clean energy technology that can directly convert biomass to electricity. However, its low power density is a main limitation to be used as a new energy source. To overcome this limitation, we focused on the anode improvement in a mediator-type MFC using P. vulgaris as a biocatalyst. Fuel cell performance increased when the anode was coated with carbon black or polypyrrole. The best performance was observed when polypyrrole/carbon black (Ppy/CB) composite material was coated on a carbon paper electrode. Our obtained value of 452 mW $m^{-2}$ is the highest value among the reported ones for the similar system. The effects of amount of Ppy/CB, mediator concentration, and amount of P. vulgaris have also been examined.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회B
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• pp.2126-2130
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• 2008

Gasoline engine have proved its utility in light, medium and heavy duty vehicle in every sector of the world community. The concern about long term availability of petroleum and the increasing threat for the environment by the increasing load of vehicular emission, compel the technology to upgrade itself for meeting the challenges. CNG is environmentally clean alternative to the existing SI Engines with out much change in the hardware. Many researchers have found this as a potential substitute to meet the energy requirement. Higher octane number and higher self ignition temperature make it a good gaseous fuel. Although power output is slightly lesser than the gasoline it's thermal efficiency is better than the gasoline for the same SI Engine. Results showed that reduced CO, hydrocarbon emissions is a favorable outcome, with slight increase in $NO_x$ emission when compared with gasoline fuel to dual fuel mode in the existing SI Engines.

• 한국자동차공학회논문집
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• 제10권5호
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• pp.107-113
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• 2002

LPG has been well known as a clean alternative fuel for vehicles. Recently, several LPG engines for heavy duty vehicles have been developed, which can replace some diesel engines that are one of the main sources for air pollution in the urban area. Because cylinder bore of heavy duty LPG engine is larger than that of gasoline, the study of knock characteristics of LPG engine are needed. In this study, the knock characteristics were investigated with various engine speed, air excess ratios and LPG fuel compositions. Experimental results indicated that the Knock occurrence probability decreases with increasing engine speed and propane fraction of fuel. The Knock occurrence probability is highest at excess air ratio of 1 and decreases as the mixture strength became leaner.

• 한국자동차공학회논문집
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• 제1권2호
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• pp.34-41
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• 1993

In order to reduce harmful substances such as particulates and nitric oxides emitted from diesel engine, man kinds of methodology like high pressure spray of diesel fuel oil, exhaust gas recirculation, emulsified fuel usage and dual fuelling have been studied. Dual fuelling of a diesel engine with hydrogen which is well-known as the clean fuel and has excellent combustibility is expected to be effective in reducing harmful substances from diesel engine. This experimental study was conducted to investigate the effect of premixed hydrogen with intake air on the performance and particulate emission characteristics using a single cylinder, prechamber type diesel engine. As a result, it was clarified that a hydrogen-premixed diesel engine can be operated in the state of lower particulate emission and slightly aggravated fuel economy, compared with the conventional diesel engine.

• International Journal of Automotive Technology
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• 제8권5호
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• pp.533-542
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• 2007

The two stroke spark ignition engine is the greatest contributor of the total vehicular pollution in a country like India. It is therefore an item that requires great attention in order to reduce fuel consumption and its concomitant pollution. The use of strong magnetic charge in the fuel line gives a complete and clean burn so that power is increased while operating expenses are reduced. The magnetic flux on the fuel line dramatically reduces harmful exhaust emissions while increasing mileage, thereby saving money and improving engine performance. It increases combustion efficiency and provides higher-octane performance. The experimental results show that the magnetic flux on fuel reduces the carbon monoxide emission up to 13% in a base engine, 23% in a copper-coated engine and 29% in a zirconia-coated engine.

• 한국전기전자재료학회논문지
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• 제23권7호
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• pp.530-533
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• 2010

The proton exchange membrane fuel cell (PEMFC) holds great promise of clean power. However, in practical applications which use the PEMFC as the power source, the output voltage from the fuel cell undergoes a transient response especially during acceleration and deceleration. This paper presents the relationships between the charge curves of the internal voltage rise, discharge curves of the internal voltage drop, the voltage with a time constant $V_{\tau}$ and finally, the load and time constant $\tau$ of $FC_1$ and $FC_2$, connected both in series and in parallel.

• 해양환경안전학회지
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• 제16권3호
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• pp.301-306
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• 2010

DME는 환경 친화적인 특성으로 인해 현재 전 세계적으로 주목을 받고 있다. 지금까지 DME는 매연을 적게 생산하는 청정 에너지라는 특성으로 인해 디젤 자동차의 주요 대체 에너지로서 연구되어 왔다. 이에 본 연구에서는 에틸렌 대향류 확산화염에 DME를 5%, 14% 및 30% 혼합했을 때, DME의 혼합 비율에 따른 매연의 수밀도 및 크기에 대한 영향을 조사하였다. 레이저 투과법 및 산란법을 이용해 수밀도 및 크기를 측정하였다. 그 결과 DME를 30% 혼합한 경우에는 매연이 감소한 반면, 5%와 14%의 혼합 비율에서는 매연이 증가하는 경향을 나타내었다. 이 결과는 DME가 매연 생성이 적은 청정 연료로 알려진 것과는 달리 에틸렌 확산화염 내에서는 DME의 혼합에 따라 매연 생성이 증가될 수 있다는 것을 의미한다.

• 공업화학
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• 제24권3호
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• pp.285-290
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• 2013

최근 비식용 바이오매스 자원인 미세조류를 이용하여 배가스 내의 이산화탄소를 저감함과 동시에 바이오연료를 생산하는 공정이 개발되고 있다. 미세조류 바이오연료 전환 공정은 미세조류 경작, 수확, 추출, 전환 등의 다양한 공정들이 연속적으로 이용된다. 이에 따라 실제 에너지 생산 효과에 대한 우려가 여전히 존재한다. 본 연구는 석탄 발전소에서 배출되는 배가스를 이용하여 파일럿 광생물 반응기에서 생산되는 미세조류를 대상으로 바이오연료 전환에 따른 실에너지 효율을 계산하였다. 에너지 전환 공정은 전이에스터화, 열분해 공정을 선정하였으며 미세조류의 지질 함량에 따른 영향을 검토하였다. 미세조류 바이오연료 전환 공정들은 경작, 수확, 추출, 전환 등에 소요되는 에너지보다 많은 양의 에너지를 가지는 바이오연료를 생산할 수 있으며 지질 함량이 높은 미세조류는 열분해보다 전이 에스터화 반응이 효과적이었다.

• 청정기술
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• 제11권4호
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• pp.171-179
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• 2005

바이오디젤은 동물성 또는 식물성 유지를 알코올과 반응시켜 생성된 물질로서 경유와 유사한 특성을 가지고 있어 기존 제품에 혼합하여 연료로 사용하고 있으며 대기오염을 감소시키는 효과와 재생 가능한 바이오매스로부터 생산된다는 장점을 가지고 있다. 기존의 알칼리 또는 산성 촉매를 사용하는 공정에 비하여 초임계 상태의 메탄올을 사용하여 바이오디젤을 제조하는 공정은 반응시간이 짧고 촉매를 사용하지 않아 분리/정제 공정이 단순하여 경제적이기 때문에 최근 많은 연구가 진행되고 있다. 특히, 국내의 경우 연간 20만톤의 폐식용유가 발생하고 있기 때문에 이의 재활용 방안으로 국내 고유의 초임계 공정이 상업화 될 경우 막대한 에너지 회수와 이산화탄소 저감 그리고 환경 개선 효과를 기대할 수 있을 것으로 사료된다.

• Journal of Advanced Marine Engineering and Technology
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• 제34권3호
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• pp.351-359
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• 2010

Bi-fuel system in a spark ignition engine (SIE) is a rising phenomena in today's automobile technology. In a gasoline driven vehicle, alternatively adoption of compressed natural gas (CNG) could be used as a potential substitute to meet the energy requirement and this is possible by some minor changes in the hardware of the existing engine. Gasoline engine is widely used in the passenger cars, light, medium and heavy duty vehicles but the consumption status of the petroleum is decreasing worldwide and at the same time environmental pollution from automobiles is seriously establishes as a threat for every nation in respect to global warming and climate changes. Now-a-days most vehicles operate using CNG for its popularity stems, clean burning properties and cost effective solution compared to other alternative fuels. It refers as a good gaseous fuel because of its high octane number and self ignition temperature. Though the power output is slightly lesser than the gasoline fuel; its thermal efficiency is better than the gasoline for the same SIE. The research paper highlights the reduction of CO, reasonable outcomes of HC emissions with minor increase in $NO_x$ emissions compared with the gasoline fuel to bi-fuel mode in the SIE that meets the emission challenges.