• Resources Recycling
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• v.9 no.1
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• pp.27-35
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• 2000

Characteristics of pyrolytic gasification were examined for the waste tire and 7 types of waste synthetic resin, using a bench scale experimental facility. the product gas temperature of waste tires was $150~300^{\circ}C$ and the temperature profile in the combustion zone of the lower reactor part tended to be clearly distinguished from that in the gasification zone of the upper part. However, in the case of waste synthetic resins, there were no clear distinction and temperature fluctuation was severe, depending on the reaction time. Product gas quantity, which depends on that of supplied (1st) air, was found to be 105~135% of the 1st air amount at the steady state. The concentration of noncombustible components in product gas was 80~90 vol.% and the high heating value of the product gas calculated from gas compositions was 1,500~3,000 kcal/N㎥ for waste tire, and 300~2,900 kcal/N㎥ for waste synthetic resins, respectively. Heating value of product gas and combustible gas concentration were increased in proportion to 1st air amount when 1st air amount is below $0.35N\textrm{m}^3$/min.

• Korean journal of food and cookery science
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• v.21 no.4 s.88
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• pp.475-481
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• 2005

This study was conducted to determine the antioxidant activity of paprika in a lard model system. The effect of paprika (ground fresh paprika (FP) $3\%$, $50^{\circ}C$ far-infrared ray dried Paprika Powder (PP) $3\%$ and $5\%$) on the inhibition of lipid oxidation in lard was examined by pH, peroxide value (POV), thiobarbituric acid (TBA) value and fatty acid composition during 8 days of storage at $4^{\circ}C$. With paprika, POV and TBA values in lipid oxidation of lard were significantly lower than those of the control without paprika. Especially, in lard with FP $3\%$, there was hardly any change of lipid oxidation values such as POV, TBA values and destruction of unsaturated fatty acid inhibiting lipid oxidation. Heating of paprika during far-infrared ray drying decreased the inhibition effect on lipid oxidation in the lard model system probably due to loss of antioxidant substances, such as vitamin C, polyphenols and carotenoids including capsanthin, by heating. Therefore, FP containing a hish amount of antioxidant substance could be used as a good antioxidant in Pork Products containing large amounts of lard.

• Transactions of the Korean Society of Automotive Engineers
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• v.14 no.4
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• pp.84-91
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• 2006

In this study, the effect of EGR and fuel injection pressure on the characteristics of combustion and emission performance of the common-rail diesel engine is investigated using DME fuel as a smoke-free alternative fuel. Because the heating value and density of DME fuel are lower than those of diesel fuel, the injection duration of the DME engine is relatively longer than the injection duration of the diesel engine with the same injection pressure. However, the higher injection pressure can shorten the injection duration for the DME engine. Although the smoke level of the DME engine is much lower than that of the diesel engine, the NOx is at a level similar to that of the diesel engine. As a proposed solution for this, the EGR technique is empirically applied to the DME engine. In the experiments, the injection pressure was changed from 200bar to 400bar, and the EGR rate was limited under 40%. With the same injection timing and fuel amount, the experiment results indicated that the increase of injection pressure led to the increase of IMEP while decreasing HC and CO emissions. However, the NOx emission tends to increase as the injection pressure becomes higher. On the other hand, as the EGR rate was increased, NOx emission and A/F were reduced while the HC and CO emissions were increased. Because HC and CO emissions have the critical A/F point where the emissions of HC and CO are rapidly increased, it is proposed that the EGR rate must be limited under the critical EGR rate.

• Transactions of the Korean Society of Automotive Engineers
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• v.22 no.5
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• pp.59-65
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• 2014

Diesel engines have the superior combustion efficiency and fuel economy that they are widely used for industry, heavyduty vehicles, etc. However, its exhaust emissions have become the major concerns due to their environmental impacts. Moreover, the depletion of fossil fuels is the main issue. Therefore, it is important to look for alternative sources of energy. Bio-diesel is one of the ideal energy which has proved to be ecofriendly for more than fossil fuels. The experimental tests analysed the engine performance and emission characteristics of a diesel engine using diesel and biodiesel blended of BD25, BD45 and BD65, in order to study the use of clean fuel to meet the increasingly stringent emission regulations. The engine performance was examined by using engine dynamometer while an exhaust gas analyzer was used to examine the emission characteristics. The effect of biodiesel on engine performance were lower to diesel through comparing their HP and torque but fuel consumption was slightly increased because of biodiesel has lower heating value and higher density than diesel. However, due to the better lubricity, the brake thermal efficiency of biodiesel was higher than diesel. The emission characteristics were strongly affected by the blending ratio of diesel and biodiesel. The results showed that the smoke opacity, hydrocarbons (HC) and carbon monoxide (CO) emissions decreased while the nitrogen oxides (NOX) slightly increased.

• Journal of ILASS-Korea
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• v.16 no.3
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• pp.119-125
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• 2011

Due to the oxygen contents in biodiesel, application of the fuel to compression ignition engines has significant advantages in terms of lowering PM formation in the combustion chamber. In recent days, considerable studies have been performed to extend the low temperature combustion regime in diesel engines by applying biodiesel fuel. In this work, low temperature combustion characteristics of biodiesel blends in dilution controlled regime were investigated at a fixed engine operating condition in a single cylinder diesel engine, and the comparisons of engine performances and emission characteristics between biodiesel and conventional diesel fuel were carried out. Results show that low temperature combustion can be achieved at $O_2$ concentration of around 7~8% for both biodiesel and diesel fuels. Especially, by use of biodiesel, noticeable reduction (maximum 50% of smoke was observed at low and middle loads compared to conventional diesel fuel. In addition, THC(total hydrocarbon) and CO(Carbon monoxide) emissions decreased by substantial amounts for biodiesel fuel. Results also indicate that even though about 10% loss of engine power as well as 14% increase of fuel consumption rate was observed due to lower LHV(lower heating value) of biodiesel, thermal efficiencies for biodiesel fuel were slightly elevated because of power recovery phenomenon.

• Journal of the Korean Applied Science and Technology
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• v.34 no.1
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• pp.1-11
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• 2017

Bio-oil has attracted considerable interest as one of the promising renewable energy resources because it can be used as a feedstock in conventional petroleum refineries for the production of high value chemicals or next-generation hydrocarbon fuels. Zeolites have been shown to effectively promote cracking reactions during pyrolysis resulting in highly deoxygenated and hydrocarbon-rich compounds and stable pyrolysis oil products. In this study, catalytic pyrolysis was applied to upgrade bio-oil from yellow poplar and then fuel characteristics of upgraded bio-oil was investigated. Yellow Poplar(500 g) which ground 0.3~1.4 mm was processed into bio-oil by catalytic pyrolysis for 1.64 seconds at $465^{\circ}C$ with Control, Blaccoal, Whitecoal, ZeoliteY and ZSM-5. Under the catalyst conditions, bio-oil productions decreased from 54.0%(Control) to 51.4 ~ 53.5%, except 56.2%(Blackcoal). HHV(High heating value) of upgraded bio-oil was more lower than crude bio-oil while the water content increased from 37.4% to 37.4 ~ 45.2%. But the other properties were improved significantly. Under the upgrading conditions, ash and TAN(Total Acid Number) is decrease and particularly important as transportation fuel, the viscosity of bio-oil decreased from 6,933 cP(Control) to 2,578 ~ 4,627 cP. In addition, ZeoliteY was most effective on producing aromatic hydrocarbons and decreasing of from the catalytic pyrolysis.

• Journal of the Korea Institute of Building Construction
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• v.16 no.3
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• pp.247-255
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• 2016

The exothermic property of electrical conductivity concrete would allow the heating system of house or snow melting system of tunnel, road or bridge deck. This study was performed on electric resistance, exothermic property and mechanical property of the mortar with graphite of carbon-based conductive material as a fundamental research for the heat conductive concrete development. As the results of this experiment, the increasement on the amorphous graphite substitution rate was found to decrease in the compressive strength, however, the electric resistance was found to be significantly lower. And, in order to demonstrate the exothermic property, the graphite was found to be included more than 15% of the total mortar volume. When low electric resistance obtained with a certain level of the graphite inclusion, exothermic value and applied voltage has a higher correlation, and the exothermic value and the square of the voltage appeared to be in a proportional relationship.

• Clean Technology
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• v.26 no.1
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• pp.79-87
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• 2020

The bio-oil produced from the fast pyrolysis of lignocellulosic biomass contains a high amount of oxygenates, causing variation in the properties of bio-oil, such as instability, high acidity, and low heating value, reducing the quality of the bio-oil. Consequently, an upgrading process should be recommended ensuring that these bio-oils are widely used as fuel sources. Catalytic fast pyrolysis has attracted a great deal of attention as a promising method for producing upgraded bio-oil from biomass feedstock. In this study, the fast pyrolysis of tulip tree was performed in a bubbling fluidized-bed reactor under different reaction temperatures, with and without catalysts, to investigate the effects of pyrolysis temperature and catalysts on product yield and bio-oil quality. The system used silica sand, ferric oxides (Fe₂O₃ and Fe₃O₄), and H-ZSM-5 as the fluidized-bed material and nitrogen as the fluidizing medium. The liquid yield reached the highest value of 49.96 wt% at 450 ℃, using Fe₂O₃ catalyst, compared to 48.45 wt% for H-ZSM-5, 47.57 wt% for Fe₃O₄ and 49.03 wt% with sand. Catalysts rejected oxygen mostly as water and produced a lower amount of CO and CO₂, but a higher amount of H₂ and hydrocarbon gases. The catalytic fast pyrolysis showed a high ratio of H₂/CO than sand as a bed material.

• Applied Chemistry for Engineering
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• v.20 no.2
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• pp.223-226
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• 2009

In this study, we investigated the recovery of copper and synthetic fuel from the waste wire by low temperature pyrolysis which can overcome problems of the recent incineration methods. Through thermal decomposition process of waste wire, we achieved the big advantage of getting usable resources as the forms of copper and fuel with a very high value. The TG/DTA and small-scale reaction experiments were carried out to determine an optimum temperature for waste wire pyrolysis. And the pyrolysis was done at 350, 450, and $550^{\circ}C$, respectively, and heating rate of the TG/DTA was $5^{\circ}C/min$ untill $700^{\circ}C$. The result shows that the optimum temperature range for dehydrochlorination of PVC was $280{\sim}350^{\circ}C$, as a lower temperature range than $400{\sim}550^{\circ}C$ of PE and PP. Practically over 95% of copper metal and synthetic fuel, which has the 8027 kcal/kg as a calorific value, were recovered from the waste wire samples.

• Journal of the Korea Organic Resources Recycling Association
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• v.16 no.4
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• pp.74-81
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• 2008

Due to separate discharge of food waste, large incinerating facilities for municipal waste show the phase change that combustible contents have been increasing while the concentrations of water have been decreasing when wastes are brought in. This phase change of wastes leads to the increase of exothermic value when wastes are carried in, which causes the problems to make the durability of incinerating facilities weak and lower the capacities of them. In accordance with these problems, this study was carried out to present effective plans to operate incinerating facilities as the quantities of municipal wastes of Incheon have been gradually increasing. We examined the problems caused by the phase change of municipal waste in Incheon and managing plans to control the amounts of heat output when intermixed incineration of food waste is conducted. It is concluded that we could carry out the optimized operation of incinerating facilities as well as produce economic effect to reduce processing costs when we conduct the intermixed incineration of food waste and municipal waste, in the trend that the amounts of heat output generated by wastes are gradually increasing. This is because this operation of intermixing incineration contributes to reducing the amount of exothermic heat.