• 한국신재생에너지학회:학술대회논문집
• /
• 2008.10a
• /
• pp.149-152
• /
• 2008

Three properties of food waste are water 80%, ash 3%, volatile matter 17%. When food waste goes through treatment process such as removal of foreign substances, removal of water as well as sodium, dryness, and pulverization, it transforms into 4,000Kcal/kg purverized fuel if moisture content is below 13%. Fuel ratio(fixed carbon/volatile matter) of purverized fuel is low compared with bituminuous coal. Ignition temperature measured by thermogravimetry analyzer is about $460^{\circ}C$. Combustion test of purverized fuel have been performed using energy recovery facility which include storage tank of dewatered cake, dryer, hammer mill, combuster including burner, boiler, flue gas treatment equipment. When 160-180 kg/hr of fuel is steadily supplied to burner for 3 hours, combueter temperature reaches about $1000^{\circ}C$ and CO is 77-103ppm at 1.55 excess air ratio and SOx and Cl are under 2ppm and 1ppm, respectively. This experiment demonstrate that purverized fuel made from food waste could be an alternative clean energy for high oil price era

• Journal of the Korean Society of Combustion
• /
• v.15 no.3
• /
• pp.40-47
• /
• 2010

Calorific value of mixed gas, like liquefied natural gas (LNG), is strongly depends on its compositions which are affected by the mining place and producing time. The variation in calorific value have an direct influence on the combustion characteristics and performances of boiler, burner, vehicle, power plants etc. Thus, developing experimental method to measure exact calorific value is becoming an issue in the related industrial fields. Flame calorimeter is developed to get calorific value at the dynamic equilibrium state using electric substitution method. Refrigerant-11 carries heat from combustor and/or heater to the Peltier elements which pumped it out to the cooling water. It is found out that error in the measured calorific value of methane is 2.86% compared with the theoretical one. Developed design technique and the experimental data will be applied to design the national standard gas calorific value measuring apparatus.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.15 no.6
• /
• pp.35-40
• /
• 2016

In this study, the thermal and fluid dynamic characteristics for the coating process of large-sized water pipes was studied by heating the inside of a pipe directly with a gas burner. Heat and flow analyses were performed on large pipes with various inlet shapes. Using large pipes for coating was shown to be the proper shape for heating large pipes uniformly. This type has a screw with a diameter of 200 mm installed at the inlet to provide a rotational motion to the heating air. The rotational motion resulted in a uniform temperature distribution that ranged from $289.1^{\circ}C$ to $352.1^{\circ}C$ The optimized geometric configuration of the inlet of the pipe successfully and uniformly enhanced the thermal characteristics of the devised temperature limit.

• Transactions of the Korean hydrogen and new energy society
• /
• v.32 no.6
• /
• pp.534-541
• /
• 2021

In this study, a novel microwave-matrix reformer was proposed to convert CH₄, which is a major component, to a high quality hydrogen energy. And to identify this performance, it was investigated for O₂/C ratio, steam feed amount and reformed gas recirculation which are affected for methane conversion and product gas yield. Through the parametric screening studies, optimal operating conditions were that O₂/C ratio, steam feed amount and recirculation rate were 1.1, 10 mL/min and 30 L/min. In this conditions, CH₄ conversion was 68.1%, H₂ selectivity 77.2 and H₂/CO ratio 2.62 which are possible applying SOFC stack for RPG (residential power generator).

• Journal of Biosystems Engineering
• /
• v.25 no.6
• /
• pp.481-488
• /
• 2000

This study was initiated in order to find alternative fuel substituting for light oil the most common fuel for heating greenhouse. The tire oil used in this research was produced by pyrolysis process, one of the final products besides steel string and carbon black in which waste tires as a form of chopped pieces broken by shredding machine are heated up to 200~30$0^{\circ}C$ with maximum restraining of oxygen supply. In order to justify light oil equivalent qualities in tire oil combustion characteristics were defined in the way of comparing kinetic viscosities in the wide range of temperature flame sizes and exhaust gas components in the various combustion conditions. We found that kinetic viscosity of tire oil was lower than light oil by 1 to 2 cSt in the temperature range showing better flowing mobility in the fuel line of the burner and no significant difference in flame size between the two oils in the all combustion treatments. However much more NO and SO$_2$ were detected from the exhaust gases of tire oil than light oil combustions. In fact tire oil contains more nitrogen and total sulfur, by 25 times and 40 times respectively than light oil according to the composition analysis. Tolerable limit for SO$_2$discharge amount defined by the national air pollution standards is under 540ppm so tire oil combustion satisfies the requirement though. It is desirable if sulfur and nitrogen filtering process shall be added in the tire oil production line. Except the exhaust gas components all greenhouse heating qualities of tire oil including hot air temperature are very identical to those of light oil.

• International Journal of Air-Conditioning and Refrigeration
• /
• v.15 no.1
• /
• pp.34-45
• /
• 2007

In order to reduce the compression power and to use the overall energy contained in LNG effectively, a combined cycle is devised and simulated. The combined cycle is composed of two cycles; one is an open cycle of liquid/solid carbon dioxide production cycle utilizing LNG cold energy in $CO_2$ condenser and the other is a closed cycle gas turbine which supplies power to the $CO_2$ cycle, utilizes LNG cold energy for lowering the compressor inlet temperature, and uses the heating value of LNG at the burner. The power consumed for the $CO_2$ cycle is investigated in terms of a solid $CO_2$ production ratio. The present study shows that much reduction in both $CO_2$ compression power (only 35% of the power used in conventional dry ice production cycle) and $CO_2$ condenser pressure could be achieved by utilizing LNG cold energy and that high cycle efficiency (55.3% at maximum power condition) in the gas turbine could be accomplished with the adoption of compressor inlet cooling and regenerator. Exergy analysis shows that irreversibility in the combined cycle increases linearly as a solid $CO_2$ production ratio increases and most of the irreversibility occurs in the condenser and the heat exchanger for compressor inlet cooling. Hence, incoming LNG cold energy to the above components should be used more effectively.

• International Journal of Highway Engineering
• /
• v.18 no.2
• /
• pp.29-36
• /
• 2016

PURPOSES: The objective of this study is to determine the milling temperature that minimizes the binder-induced damage to the aggregate; this is achieved by evaluating the temperature dependence of the viscosity of the asphalt binder, with the aim of developing an effective heating process for warm in-place recycling. METHODS : The validity of the indoor test was confirmed by conducting an internal heating test based on the on-site heating test. In addition, the adhesive power of the binder was measured at various temperatures ($30^{\circ}C$, $40^{\circ}C$, $50^{\circ}C$, $60^{\circ}C$, $70^{\circ}C$) via three types of measuring methods. RESULTS: The surface temperature spectrum of field test was slight different with that of laboratory test. But, the spectra of inner temperature between the field and the laboratory was almost similar. Also, the adhesion of the asphalt binder was measured from $30^{\circ}C$ to $70^{\circ}C$. The adhesion of the binder was significantly decreased from $60^{\circ}C$. Contrary to other temperature, the adhesion was slightly changed from $60^{\circ}C$ to $70^{\circ}C$. Also the inner temperature between two different heating methods was shown similar temperature spectra. CONCLUSIONS: The pavement heating temperature spectrum of hot in place recycling method was simulated by a laboratory test. Based on this study, the optimum temperature was $60^{\circ}C{\sim}70^{\circ}C$ for reducing aggregate damage during milling process. The susceptibility heating method developed in this study can be maintained the optimum inner temperature range.

• Journal of Biosystems Engineering
• /
• v.33 no.2
• /
• pp.124-129
• /
• 2008

In this study, fuel qualities including kinematic viscosity and pour point in the various temperature, calorific value and combustion characteristics of two biodiesels based on the soybean and waste oil blended with light oil were investigated and discussed in order to figure out to confirm fuel compatibility taking the place of light oil in the hot air heater or boiler. As biodiesel content ratio increased calorific value of biodiesel decreased, and the difference was 13% between 100%-biodiesel and light oil. In general, pour points of the biodiesels were higher than light oil, and as biodiesel content ratio increased pour point increased. About 15 cSt was the pour point of biodiesels and light oil, which occurred at 3 to $4^{\circ}C$ in the biodiesels and $-25^{\circ}C$ in the light oil. Flame dimensions of biodiesels and light oil were almost same at the same combustion condition in the burner of the hot air heater. CO concentrations in the exhaustion gas were far lower than those of the light oil. Though pour point of biodiesel is a little inferior to light oil, still biodiesel can be an alternative fuel substituting for light oil in combustion system without much modifying the current oil combustion mechanism.

• 한국연소학회:학술대회논문집
• /
• 2015.12a
• /
• pp.295-296
• /
• 2015

We presented the methods calculating the reduction efficiency of nitrogen oxide for the low $NO_x$ burner as the pollution prevention facilities. The standard $NO_x$ concentration was used on the emission factor of LNG, $3.7g/m^3$. The $NO_x$ reduction efficiency based on the $NO_x$ concentration was presented and the relationships between the $NO_x$ concentration and the emission factor or the specific heat emission factor were derived. These results could be accurately reflected on calculating the amount of the nitrogen oxide emissions. In addition, according to the arrangement of the low $NO_x$ burners the methods of applying their $NO_x$ reduction efficiency were proposed. The $NO_x$ reduction efficiency for the facilities consisting of the low $NO_x$ burners and the non-low $NO_x$ burners could be estimated with information about the reduction efficiency of each low $NO_x$ burners, the fuel consumption rate, and the heating value of fuel.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
• /
• 2006.05a
• /
• pp.412-419
• /
• 2006

An Experimental study was conducted on $CO_{2}$ recycle combustion heating system using pure oxygen instead of conventional air as an oxidant, which is thereby producing a flue gas of mostly $CO_{2}$ and water vapor($H_{2}O$ and water vapor($H_{2}O$) and resulting in higher $CO_{2}$ concentration. The advantages of the system are not only the ability to control high temperatures characteristic of oxygen combustion with recycling $CO_{2}$ but also the possibility to reduce NOx emission in the flue gas. A small scale industrial reheating furnace simulator and specially designed variable flame burner were used to characterize the $CO_{2}$ recycle oxy-fuel combustion, such as the variations of furnace pressure, temperature and composition in the flue gas during recycle. It was found that $CO_{2}$ concentration in the flue gas was about 80% without $CO_{2}$recycle. The furnace temperature and pressure and pressure were decreased due to recycle and the NOx emission was also reduced to maintain under 100ppm.