• 유기물자원화
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• 제18권1호
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• pp.66-72
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• 2010

본 연구는 경기도 A지역 자원회수시설에서 연소온도의 변화에 따른 NOx, SOx, CO, HCL, DUST의 발생변화와 보일러 배출가스 온도, 보일러 출구산소 농도, 반건식 반응탑 출구온도, 촉매탑온도, 배출가스 온도의 변화를 분석하였다. SOx, CO, Hcl, DUST는 자원회수시설 내의 연소온도가 상승함에 따라 거의 5 ppm 미만의 일정한 값을 유지한 반면 NOx 는 40 ppm에서 70 ppm으로 증가하는 추세였다. 한편 보일러 배출가스 온도와 촉매탑 온도는 일정치를 유지하였으나 보일러 출구의 산소농도는 조금씩 감소하는 결과를 나타내었다.

• International Journal of Automotive Technology
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• 제3권1호
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• pp.41-46
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• 2002

Effect of secondary air injection (SAI) on hydrocarbon reduction has been investigated in a single cylinder Sl engine operating at cold-steady/cold-start conditions. The hydrocarbon emission and exhaust gas temperature with and without catalytic converter were compared with continuous and synchronized SAIs, which injected secondary air intermittently into exhaust port. Effects of SAI location, SAI pressure, SAI timing, and location of catalytic converter have been investigated and the results are compared for both SAls with base condition. At cold-steady condition, the rate of HC reduction increased as the location of SAI was closer to the exhaust valve for both synchronized and continuous SAls. The emission of HC decreased with increasing exhaust-A/F when it was rich, and was relatively insensitive when it was lean. The timing of SAI in synchronized SAI had significant effect on HC reduction and exhaust gas temperature and the synchronized SAI was found to be more effective in HC reduction and exhaust gas temperature compared to the continuous SAI . At cold-start condition, when the catalytic converter was located 20 cm downstream from the exhaust port exit, the catalytic converter warm-up period for both SAls decreased by about 50%, and the accumulated hydrocarbon emission during the first 120 s decreased about by 56% and 22% with the synchronized and continuous SAIs, respectively, compared to that of the base condition.

• Journal of Biosystems Engineering
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• 제26권5호
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• pp.441-448
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• 2001

Hot air heater with light oil combustion is used as the most common heater for greenhouse heating in the winter season. However, exhaust gas heat discharged to atmosphere through chimney reaches up to 10~20% of total heat capacity of the oil burred. In order to recover the heat of this exhaust gas and to use for greenhouse heating, the heat pipe type exhaust heat recovery system was manufactured and tested in this experiment. The system consisted of a heat exchanger made of heat pipes, ø15.88${\times}$600mm located in the rectangular box of 675(L)${\times}$425(W)${\times}$370(H)mm, an air suction fan and air ducts. The number of heat pipe was 60, calculated considering the heat exchange amount between exhaust gas and air and heat transfer capacity of a heat pipe. The working fluid of heat pipe was acetone because acetone is known for its excellent heat transfer capacity. The system was attached to the exhaust gas path. According to the performance test it could recover 53,809 to 74,613kJ/h depending on the inlet air temperature of 12 to -12˚at air flow rate of 1.100㎥/h. The temperature of the exhaust gas left the heat exchanger dropped to 100$^{\circ}C$ from 270$^{\circ}C$ after the heat exchange between the suction air and the exhaust gas.

• 한국마린엔지니어링학회:학술대회논문집
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• 한국마린엔지니어링학회 2002년도 춘계학술대회논문집
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• pp.75-82
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• 2002

The effects of intake mixture temperature on performance and exhaust emissions under four kinds of engine loads were experimentally investigated by using a four-cycle four-cylinder, swirl chamber type, water-cooled diesel engine with scrubber EGR system operating at three kinds of engine speeds. The purpose of this study is to develop the scrubber exhaust gas recirculation(EGR) control system for reducing $NO_x$ and soot emissions simultaneously in diesel engines. The EGR system is used to reduce NOx emissions. And a novel diesel soot-removal device with a cylinder-type scrubber which has five water injection nozzles is specially designed and manufactured to reduce soot contents in the recirculated exhaust gas to the intake system of the engine. The influences of cooled EGR and water injection, however, would be included within those of scrubber EGR system. In order to study the effect of intake mixture temperature, a intake mixture heating device which has five heating coils is made of a steel drum. It is found that the specific fuel consumption rate is considerably elevated by the increase of intake mixture temperature, and that NOx emissions are markedly decreased as EGR rates are increased and intake mixture temperature is dropped, while soot emissions are increased with increasing EGR rates and intake mixture temperature.

• Journal of Biosystems Engineering
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• 제10권2호
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• pp.1-11
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• 1985

A double pipe grain heater using engine exhaust gas as a heat source was developed. The performance of the grain heater was examined with soybeans as a test material experimentally and numerically using a mathematical model constructed. The following conclusions were drawn: 1. The modified screw conveyor used in the grain heater has a characteristic of decreasing capacity with increasing speed at speeds above 60 rpm. Operation with speeds below 60 rpm is recommended. 2. Heating soybeans by the heater at soybean flow rate up to 100 kg/hr, inlet temperature of the exhaust gas to the heater are recommended as above $400^{\circ}C$, $300^{\circ}C$, and $200^{\circ}C$ roughly for a 2, 5, and 10 kW engine, respectively. 3. Temperature increments of soybean by the heater at soybean flow rates ranged from 25 to 100 kg/hr are in the ranges of $6^{\circ}C-35^{\circ}C$, $15^{\circ}C-88^{\circ}C$, and $15^{\circ}C-140^{\circ}C$ with exhaust gas from a 2, 5, and 10 kW engine, respectively, at an exhaust temperature of $500^{\circ}C$. 4. Thermal efficiency of the heater at soybean flow rates ranged from 25 to 100 kg/hr are in the ranges of 35-37%, 28-34%, and 20-29% with exhaust gas from a 2, 5, and 10 kW engine, respectively. 5. The grain heater can be used to heat the other grain, also, without any bad effect from the exhaust gas used as a heat source.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집D
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• pp.115-120
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• 2001

The present study examined the possibility of $NO_{x}$ reduction in the high temperature industrial furnaces. duct burner of gas turbine cogeneration and two-stage gas turbine combustor. The experimental study was carried out for the diffusion flame of second stage combustor with the variations of oxygen concentration and supplying rate of hot exhaust gas from first stage combustor. It also examined the flammability range and $NO_{x}$ formation of the second stage combustor in which the fuel is supplying into the mixture of oxygen hot exhaust gas from first stage combustor. The results show that the enrichment of oxygen and increase of exhaust gas lead to increase the $NO_{x}$ up to 50 ppm with 23% $O_{2}$ condition.

• Corrosion Science and Technology
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• 제22권5호
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• pp.351-358
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• 2023

Although many thermal power plants use heat recovery systems, high exhaust gas temperatures are maintained due to corrosion at dew points and ash deposits caused by condensate formation. The dew point of exhaust gas is primarily determined by the concentration of SO₃ and steam, and various experiments and calculation equations have been employed to estimate it. However, these methods are known to be less suitable for exhaust gases with low SO₃ concentrations. Therefore, in this study, since the temperature of the exhaust gas is expected to decrease due to the low-load operation of the coal-fired power plant, sulfuric acid condensation and low-temperature corrosion are anticipated. We aimed to conduct a quantitative evaluation to propose ways to prevent damage by limiting operating conditions and improving facilities. The experimental results showed that the corrosion rate increased linearly with rising temperatures at a certain sulfuric acid concentration. Furthermore, variations in sulfuric acid concentrations generated during the current power plant operation process did not significantly affect the dew point, and the dew point of sulfuric acid under these conditions was observed to be between 120 - 130 ℃.

• 동력기계공학회지
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• 제3권3호
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• pp.44-53
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• 1999

This study is concerned with the emission characteristics of kerosene fan heater, which is burned with kerosene and water droplets simultaneously in the burner, in order to prohibit the emissions of harmful exhaust gas and reduce smell caused by incomplete combustion, and the addition of water droplets to the conventional kerosene fan heater was performed by ultrasonic atomizer. For the investigation of this study, the measurement of exhaust gas components and exhaust gas temperature was carried out by using an automatic combustion gas analyser and $NO_x$ analyser, and the measurement of consumption weight of oil and water was obtained by using electric digital balance. Consequently, according as the water percent weight ratio of about $21{\sim}23%$ was supplied for this study, it was found that the combustion-generated $NO_x$ and CO emissions were reduced very largely, but the emissions of $O_2\;and\;CO_2$ and the temperature of exhaust gas were not changed.

• 자원리싸이클링
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• 제12권1호
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• pp.41-47
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• 2003

대기에 방치된 생석회의 상온에서 내수화성을 향상시키기 위해 생석회의 탄산화반응과 수화반응실험을 수행하였다. 제강공정에서 사용시까지 수화반응을 억제시키기 위해서는 생석회 표면을 약 6%정도 탄산화시킬 필요가 있었다. 생석회의 탄산화를 위한 회전로 배가스 재순환이 평형연소온도 및 NOx농도에 미치는 영향을 열역학적으로 계산한 결과, 배가스 부피 백분율이 증가함에 따라 연소온도와 NOx농도는 감소하였다.

• 유체기계공업학회:학술대회논문집
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• 유체기계공업학회 2002년도 유체기계 연구개발 발표회 논문집
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• pp.290-297
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• 2002

This paper presents analysis results for the effect of power control strategies on the part load performance of gas turbine based power generation systems utilizing exhaust heat of the gas turbine such as cumbined cycle power plants and regenerative gas turbines. For the combined cycle, part load efficiency variations were compared among different single shaft gas turbines representing various technology levels. Power control strategies considered were fuel only control and IGV control. It has been observed that gas turbines with higher design performances exhibit superior part load performances. Improvement of part load efficiency by adopting air flow modulation was analyzed and it is concluded that since the average combined cycle performance is affected by the range of IGV control as well as its temperature control principle, a control strategy appropriate for the load characteristics of the individual plant should be adopted. For the regenerative gas turbine, it is likewise concluded that maintaining exhaust temperature as high as possible by air flow rate modulation is required to increase part load efficiency.