• Transactions of the Korean Society of Automotive Engineers
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• v.10 no.6
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• pp.72-79
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• 2002

The main objective of this study is to investigate the relationship between chemical structure and higher heating value of reformed diesel fuels by ultrasonic irradiation. In order to analyze the chemical structure changes of the reformed diesel fuels by ultrasonic irradiation, Proton nuclear magnetic resonance spectrometer(1H-NMR) was used and to analyze the effect of higher heating values of these diesel fuels, the bomb calorimeter was used. From the study, following conclusive remarks can be made. 1) The aromatic carbon percentages and higher heating values of the reformed diesel fuels by ultrasonic irradiation increased more than the conventional diesel ones. 2) The aromatics percentages and Branch Index(BI) of the reformed diesel fuels by ultrasonic irradiation decreased more than the conventional diesel ones. 3) The higher heating values on both for conventional fuel and reformed diesel fuels by ultrasonic energy irradiation is directly proportional to aromatic carbon percentages and inversely proportional to aromatic percentages and BI for these fuels.

• 한국연소학회:학술대회논문집
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• 2002.06a
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• pp.163-170
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• 2002

The main objective of this study is to investigate the correlation of chemical structure and cetane number of reformed diesel fuels by ultrasonic irradiation. In order to analyze the effect of the chemical structure and the cetane number of reformed diesel fuels by ultrasonic irradiation, $^1H-NMR$ was used. From the study, following conclusive remarks can be made. 1) BI(=Branch Index), aromatics percentages, and $H_{\alpha}(={\alpha}-methyl$ functional group) of the reformed diesel fuels by ultrasonic irradiation decreased more than those of the conventional diesel fuel. 2) All the cetane numbers which were calculated from carbon type structure and hydrogen type distribution of the reformed diesel fuels increased more than those of the conventional diesel fuel. 3) Using predicated equation of cetane number caculated from carbon type structure is more reasonable than that caculated from hydrogen type distribution 4) BI, aromatics percentages, and $H_{\alpha}$ on both of conventional fuel and reformed diesel fuels by ultrasonic irradiation are inversely proportional to cetane number on these fuels.

• Transactions of the Korean Society of Automotive Engineers
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• v.11 no.1
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• pp.64-71
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• 2003

In order to analyze the effect of the chemical structure and the cetane number of reformed diesel fuels by ultrasonic energy irradiation, proton nuclear magnetic resonance spectrometer$(^1H-NMR)$ was used. From the study, following conclusive remarks can be made. 1) Branch Index(BI), aromatics percentages, and alpha methyl radical$(H_{\alpha})$ of the reformed diesel fuels by ultrasonic energy irradiation decreased more than the conventional ones. 2) All the cetane numbers which were calculated from carbon type structure and hydrogen type distribution of the reformed diesel fuels increased more than the conventional ones. 3) It is more reasonable to predict cetane number equation from carbon type structure than from hydrogen type distribution. 4) BI, aromatics percentages, and $H_{\alpha}$ on both for conventional fuel and reformed diesel fuels by ultrasonic energy irradiation are inversely proportional to cetane number fur these fuels.

• Transactions of the Korean Society of Automotive Engineers
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• v.9 no.4
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• pp.44-49
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• 2001

Reduced chemical kinetics mechanism has been derived, which can be applicable for autoignition model of hydrocarbon fuels, and contains 23 reactions and 18 species. The present model is validated with the experimental data, where the ignition delays of several hydrocarbon fuels, such as n-heptane, i-octane, n-decane and DME(dimethylether) are measured as equivalence ratios are varied. Especially, the effects of different fuels on ignition delays can be explained by changing the rate constants of three reactions among the present model. As a result, the proposed model can be applicable to two stage ignition model of Diesel combustion.

• Journal of the Korean Chemical Society
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• v.4 no.1
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• pp.78-80
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• 1957

Up to now, only superficial studies on the combustion velocity of smokeless fuels have been reported, while it should be a basical factor on the utilization of low quality coals and some other smokeless solid fuels. It was, therefore, difficult to choose raw material coals in manufacturing gaseous fuels. With the intent to solve above problem, we have determined combustion velocity of domestic anthracites, graphites, coalites of lignite and cokes from Japanese bituminous coal. The results show that the cokes from Japanese bituminous coal which has been used as raw material in the manufacturing gaseous fuels such as water gas, or producer gas in Korea can be replaced by some sources of domestic anthracite or coalite of lignite.

• Journal of Institute of Convergence Technology
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• v.2 no.1
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• pp.7-12
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• 2012

Spent fuels are discharged from nuclear reactors as a result of power generations. The spent fuels would be considered as a useful resources because the main constituent is uranium and some other actinides are included in them. In order to utilize the resources chemical processes should be developed to treat the spent fuels and obtain uranium and other actinides to be fueled in a fast reactor. The technologies are categorized into wet and dry processes. In this study, the current status of such technologies is summarized to give a insight and a deep understanding on nuclear fuel cycles.

• Journal of The Korean Society of Agricultural Engineers
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• v.54 no.3
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• pp.75-80
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• 2012

Gasification is a therm-chemical conversion process to convert various solid fuels into gaseous fuels under limited supply of oxygen in high temperature environment. Considering current availability of biomass resources in this country, the gasification is more attractive than any other technologies in that the process can accept various combustible solid fuels including plastic wastes. Mixed fuels of biomass and polyethylene pellets were used in gasification experiments in this study in order to assess their potential for synthesis gas production. The results showed that higher reaction temperatures were observed in mixed fuel compared to woodchip experiments. In addition, carbon monoxide, hydrogen, and methane concentrations were increased in the synthesis gas. Heating values of the synthesis gas were also higher than those from woodchip gasification. There are hundred thousand tons of agricultural plastic wastes generated in Korea every year. Co-gasification of biomass and agricultural plastic waste would provide affordable gaseous fuels in rural society.

• Journal of Hydrogen and New Energy
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• v.19 no.4
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• pp.348-358
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• 2008

Reduction reactivity and carbon deposition characteristics of mass produced oxygen carrier particle(OCN-650) have been investigated by using hydrogen, methane, syngas, and natural gas as fuels. For all fuels, the maximum conversion and oxygen transfer capacity increased as the temperature increase. The reduction rate and the oxygen transfer rate increased as the temperature increase for methane. However, those values showed maximum at 900$^{\circ}C$ for hydrogen, syngas, and natural gas. To explain consistently the change of maximum conversion, reduction rate, oxygen transfer capacity, oxygen transfer rate and degree of carbon deposition for different fuels, new parameters such as reactive carbon contents and require oxygen per input gas were adopted.

• The Microorganisms and Industry
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• v.12 no.1
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• pp.15-22
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• 1986

Chemical production by anaerobic bacterial fermentations was an important microbiological topic in the past due to both fundamental and applied aspects related to acetone-butanol production prior to its replacement by chemical synthetic routes from petroleum. Presently, the depletion and price-escalation of petroleum has regenerated a great interest in the potential of anaerobic bacteria to transform the renewable resouces such as biomass and wastes into chemical feed-stocks and fuels.

• Journal of Advanced Marine Engineering and Technology
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• v.23 no.1
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• pp.88-95
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• 1999

This study investigates the effects of different kind fuels on the flame structure by using the numerical simulation in triple flame made by a co-flowing fuels-air stream based on the elementary chemical reaction mechanism. Methane and Hydrogen were used as fuel for this study. In order to interpret the result of the study on numerical simulation Skeletal chemistry is employe as the elementary chemical reaction mechanism for methane Gutheil's as an offset ele-mentary chemical reaction mechanism for hydrogen. The result of this study is as follows. In com-parison between the apparent burning velocity change of triple flame and the one-dimensional pre-mixed flame hydrogen fuel flame is higher than methane fuel flame. The flame thrusts out for-ward in the down stream of the boundary between air-fuel mixture and air stream and a part of the flow is bent and forks out in this protruding flame so that a triple flame is originated.