• 동력기계공학회지
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• 제12권1호
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• pp.5-12
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• 2008

We measured emission characteristics of CRDI diesel engine equipped with a commercial CPF. Experimental parameters adopted a neat diesel fuel, a blend of diesel fuel with 20% biodiesel, a blend of diesel fuel with 15% biodiesel and 5% ethanol. The experiments were carried out to measure the emission and engine performance according to ESC 13-mode cycles. The maximum torque with biodiesel blend fuel is slightly lower than that of neat diesel fuel in the entire the 13-mode cycles, and 5% ethanol and 15% biodiesel blend fuel is slightly higher than that of neat diesel fuel. THC and CO emissions of the biofuel blended diesel fuel were slightly increased and decreased, and mean conversion efficiencies of THC and CO on the commercial CPF were achieved about 70$\sim$87% in the ESC 13-mode. From the measurement by the Scanning Mobility Particle Sizer(SMPS), the total number and mass of nano-sized particles by a commercial CPF were decreased about 97.8% and 96.8 % in the range of the nano-size from 10.6 to 385nm, respectively.

• Environmental Engineering Research
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• 제23권3호
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• pp.242-249
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• 2018

The use of palm oil and diesel blended with ethanol, known as a microemulsion biofuel, is gaining attention as an attractive renewable fuel for engines that may serve as a replacement for fossil-based fuels. The microemulsion biofuels can be formulated from the mixture of palm oil and diesel as the oil phase; ethanol as the polar phase; methyl oleate as the surfactant; alkanols as the cosurfactants. This study investigates the influence of the three cosurfactants on fuel consumption and exhaust gas emissions in a direct-injection (DI) diesel engine. The microemulsion biofuels along with neat diesel fuel, palm oil-diesel blends, and biodiesel-diesel blends were tested in a DI diesel engine at two engine loads without engine modification. The formulated microemulsion biofuels increased fuel consumption and gradually reduced the nitrogen oxides ($NO_x$) emissions and exhaust gas temperature; however, there was no significant difference in their carbon monoxide (CO) emissions when compared to those of diesel. Varying the carbon chain length of the cosurfactant demonstrated that the octanol-microemulsion fuel emitted lower CO and $NO_x$ emissions than the butanol- and decanol-microemulsion fuels. Thus, the microemulsion biofuels demonstrated competitive advantages as potential fuels for diesel engines because they reduced exhaust emissions.

• 동력기계공학회지
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• 제17권2호
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• pp.29-37
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• 2013

Compared to gasoline engines, diesel engines with a relatively simple ignition system are more advantageous in the application of biodeisel fuel to engine. Then in this study the comparative analysis on the spray characteristics and combustion emissions characteristic between the biodiesel(soybean oil) and diesel, the fuel for commercial diesel engine, was performed with common rail injection system. Injection pressure and ratio of biodiesel blended fuel were selected as main experimental variables. Consequently, it can be found that there is no significant difference in the macro characteristics of the spray behavior(spray penetration and spray angle) in response to change in the blend ratio of soybean oil and diesel at a fixed injection pressure, in particular, soot creation in combustion emissions in the region of low pressure was greatly affected by the blend ratio of soybean oil, however, the creation in the region of high pressure was almost unaffected by the blend ratio because of promoted atomization.

• 한국응용과학기술학회지
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• 제28권4호
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• pp.508-516
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• 2011

Hydrotreated biodiesel(HBD) is paraffinic bio-based liquid, with the chemical structure $C_nH_{2n+2}$, originating from vegetable oil(the process can also be applied to animal fat). The oil or fat is treated in a number of process, the most important being hydrogenation, in order to create a bio-based liquid diesel fuel. During the hydrogenation, oxygen is removed from the triglyceride and converted into water. Propane is formed as a by product and can be combusted and used for energy production. HBD can be used in conventional diesel engines, pure or blended with conventional diesel, due to its similar physical properties to diesel. This study reports the quality characteristics with chemical and physical properties as an alternative diesel fuel. Especially, HBD showed higher cetane value and number than FAME, and it is consisted of $C_{15}$ - $C_{18}$ n-paraffinic compounds. We also describes quality characteristics of HBD blends(2, 5, 10, 20, 30, 40, 50 vol%) in automotive diesel. HBD blends(max. 20 vol%) were the limit by the Korean specification due to poor low temperature characteristics.

• 한국응용과학기술학회지
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• 제29권3호
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• pp.450-458
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• 2012

최근 정부는 국가 온실가스를 효율적으로 감축시켜 국제적인 기후변화에 대응하기 위하여 여러 부문에서 기술개발을 진행 중에 있다. 이를 달성하기 위하여 정부는 화석연료를 대체하고 이산화탄소를 감축시키는 수단으로 바이오연료를 저탄소와 탄소중립자원으로 검토하고 있는 실정이다. 일반적으로, 목질계로부터 생산된 2세대 바이오연료는 수송부문에서 기존 화석연료를 대체하고 온실가스를 감축하는데 큰 효과가 있는 것으로 알려져 있다. 이러한 이유로 정부는 목질계 기반 바이오매스 액화연료(biomass-to-liquid fuel)에 대해 파일럿 수준으로 기술개발 중에 있다. 따라서 본 연구에서는 바이오매스액화연료 생산을 위한 동일공정으로 합성된 F-T(Fischer-Tropsch) 디젤의 연료적 특성을 연구하였다. 합성 F-T 디젤은 자동차용 경유에 단독 또는 혼합하여 사용할 수 있는 장점으로 인해 자동차용 경유엔진에 사용될 수 있다. 그 이유는 합성 F-T 디젤이 자동차용 경유와 비슷한 물리적 특성을 가지기 때문이다. 본 연구에 사용된 F-T 디젤은 Fischer-Tropsch (F-T) 공정을 이용하여 저온($240^{\circ}C$)에서 철 촉매를 가지고 합성되었다. 합성 F-T 디젤은 n-파라핀과 iso-파라핀을 함유하고, 등유와 경유 성분을 가진 $C_{12}{\sim}C_{23+}$ 분포로 이루어졌다. 합성 F-T 디젤은 합성 F-T 연료부터 증류를 통해 분리된 합성 F-T 디젤은 자동차용 경유에 비해 세탄가가 높으며, 방향족화합물은 매우 낮고, 황함량는 초저황(sulfur free) 수준으로 평가되었다. 또한 합성 F-T 디젤은 자동차용 경유와 비교하여 황과 방향족 화합물의 함량이 낮기 때문에 윤활성이 열악함을 보였다.

• 한국분무공학회지
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• 제19권4호
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• pp.155-166
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• 2014

This review will be concentrated on the spray characteristics of bioethanol and its derived fuels such as ethanol-diesel, ethanol-biodiesel in compression ignition (CI) engines. The difficulty in meeting the severe limitations on NOx and PM emissions in CI engines has brought about many methods for the application of ethanol because ethanol diffusion flames in engine produce virtually no soot. The most popular method for the application of ethanol as a fuel in CI engines is the blending of ethanol with diesel. The physical properties of ethanol and its derivatives related to spray characteristics such as viscosity, density and surface tension are discussed. Viscosity and density of e-diesel and e-biodiesel generally are decreased with increase in ethanol content and temperature. More than 22% and 30% of ethanol addition would not satisfied the requirement of viscosity and density in EN 590, respectively. Investigation of neat ethanol sprays in CI engines was conducted by very few researchers. The effect of ambient temperature on liquid phase penetration is a controversial topic due to the opposite result between two studies. More researches are required for the spray characteristics of neat ethanol in CI engines. The ethanol blended fuels in CI engines can be classified into ethanol-diesel blend (e-diesel) and ethanol-biodiesel (e-biodiesel) blend. Even though dodecanol and n-butanol are rarely used, the addition of biodiesel as blend stabilizer is the prevailing method because it has the advantage of increasing the biofuel concentration in diesel fuel. Spray penetration and SMD of e-diesel and e-biodiesel decrease with increase in ethanol concentration, and in ambient pressure. However, spray angle is increased with increase in the ethanol percentage in e-diesel. As the ambient pressure increases, liquid phase penetration was decreased, but spray angle was increased in e-diesel. The increase in ambient temperature showed the slight effect on liquid phase penetration, but spray angle was decreased. A numerical study of micro-explosion concluded that the optimum composition of e-diesel binary mixture for micro-explosion was approximately E50D50, while that of e-biodiesel binary mixture was E30B70 due to the lower volatility of biodiesel. Adding less volatile biodiesel into the ternary mixture of ethanol-biodiesel-diesel can remarkably enhance micro-explosion. Addition of ethanol up to 20% in e-biodiesel showed no effect on spray penetration. However, increase of nozzle orifice diameter results in increase of spray penetration. The more study on liquid phase penetration and SMD in e-diesel and e-biodiesel is required.

• 자원환경지질
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• 제46권6호
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• pp.593-602
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• 2013

세계적으로 석유 수급의 악화와 산유국의 정세불안으로 유가가 급등하고 매년 에너지 소비 증가와 지구온난화에 대비한 온실가스 배출절감에 대한 전 세계적 노력과 교토의정서로 대변되는 기후변화협약 발효 등으로 화석연료의 대안으로서 바이오에너지에 대한 국제적 관심이 고조되고 있다. 바이오에너지 중 바이오디젤과 바이오에탄올은 수송용 대체연료 중심으로 최근 수년간 연구개발 투자가 집중되고 있는 친환경 녹색성장의 핵심 기술이다. 이 연구는 기술의 개요와 국내외 현황을 살펴보고, 바이오디젤분야 연구논문의 연도별 발표현황, 주제 카테고리, 저널 패턴, 국가별 논문 수, 연구기관별 분석, 키워드 등을 분석하여, 국내 관련 산업 및 기술정책 수립과 연구개발에 유용한 학술자료로 활용될 수 있도록 하였다.