• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2002년도 ICCAS
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• pp.69.6-69
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• 2002

The optimal byproduct gas supply system was developed for the optimal management of the byproduct gases in the iron and steel making process based on EXCEL environment. It supplies optimal byproduct gas distribution result as well as analysis including expected electricity generation, holder level change, amount of oil consumption, energy distribution to each boiler, and efficiency of energy resource. To reflect the changing environment of the plant such as maintenance, the system was developed to easily change the optimization model for changing configuration of the system. To verify the performance of the system , case studies for various situation was performed with the developed system, a...

• 에너지공학
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• 제11권1호
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• pp.10-17
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• 2002

본 연구에서는 콘덴싱 가스보일러의 NOx와 CO 배출농도를 줄이기 위한 방안으로 원통형 버너와 열교환기를 평면으로 모사한 평면 버너와 열교환기를 제작하여 버너와 열교환기 거리에 따른 배기 특성을 검토하였다. 그리고 평면 버너 실험에서 도출한 거리에 따라 직경이 다른 3종류의 원통형 버너를 제작하여 각각의 화염 안정성과 배기 특성, 효율 등을 검토하였다. 위와 같은 연구결과에 의해 최적화된 버너를 응축 가스 보일러에 장착히여 LNG와 LPG를 연료로 사용하여 보일러에 대한 종합성능, 즉 화염 안정성, 난방효율 및 배기 특성 등을 검토하여 다음과 같은 결론을 얻었다. 난방부하 20,000kca/hr에 적합한 다공 예혼합 원통형 버너의 최적 제원을 결정하였으며, 이 버너는 당량비 0.68~0.85부근에서 turn-down ratio가 약 5 : 1 정도로 비례제어에 적합하였다. 그리고 보일러의 종합성능을 검토한 결과 난방부하 20,000 kcal/hr로 운전할 경우 LNG, LPG 모두 난방효율 97%(저위 발열량 기준)를 달성할 수 있었고 NOx와 CO 배출농도(O$_2$=0%, wet basis)는 LNG의 경우 각각 26 ppm과 85 ppm, LPG의 경우 각각 41 ppm과 113 ppm 정도로 매우 양호하였다.

• 한국수소및신에너지학회논문집
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• 제32권6호
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• pp.573-584
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• 2021

Hydrogen is evaluated as one of the new energy sources that can overcome the limitations and pollution problems of conventional fossil fuels. Although hydrogen is CO₂-free, attention is required in NO_x emission and flame stability in order to use hydrogen in existing gas fuel system. However, use of electric grids is an unrealistic strategy for decarbonization for residential and commercial heating. Instead, use of H₂ that utilizes city gas grid is suggested as a reasonable alternative in terms of compatibility with existing systems, economic feasibility, and accessibility. In this study, the thermal efficiency and NO_x performance of the boiler according to the H₂ mixture ratio and vapor humidified ratio are reviewed for a humidified NG-H₂ boiler that vapor humidity to combustion air. Mixed fuel with H₂ (20%) is almost similar to NG in terms of efficiency, flame temperature, and pollution performance. Thus, it is expected to be directly compatible with the existing NG system. If the exhaust temperature of the H₂ boiler is lowered to around 60℃ at a humidified ratio of 15-20%, the NO_x emission concentration can be suppressed to about 5-10 ppm. The level of efficiency reaches 87% of the rated load efficiency, which is equivalent to the highest grade achievable.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회B
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• pp.3259-3263
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• 2007

This paper describes the proceedings of creating countermeasures after analysis and maintenance be able to conduct operation safely in a power plant. in order to operate the power plant in a stable and reliable way, the best condition of the govemor system can be maintained through the response characteristic analysis of the control device for the pitch blade control hydraulic actuator. The fan pitch blade control hydraulic actuator of a 500MW large-scale boiler is frequently operated under normal operation conditions. Common problems or malfunctions of the pitch blade control hydraulic actuators leads to the decline of boiler thermal efficiency and unexpected power plant trip. The inlet and outlet gas can be controlled by using the fan pitch blade control hydraulic actuator in order to regulate the internal pressure of the furnace and control the frequency in the power plant facility which utilizes soft coals as a power source.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집D
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• pp.71-78
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• 2001

It was numerically studied that characteristics of fluid flow and heat transfer in a tube with disk and annular baffle for heat exchanger of condensing boiler. Using a finite volume technique and CFD code, STAR-CD, the governing equations were solved and the temperature and flow fields were investigated. The interval between tube and annular baffle, height and diameter of baffle were selected as important design parameters, and the effects of these parameters on heat transfer and fluid flow were studied. As a result, in the case of with interval, the pressure was decreased but heat transfer was increased. Also heat transfer was slowly increased as the size of disk and annular baffle were increased and the distance between baffles were decreased.

• 한국농공학회논문집
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• 제49권6호
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• pp.55-62
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• 2007

Actual states of energy utilizations were investigated and analyzed on three representative rural villages in Chungcheongnam-Do. Rural residents were almost using the ondol boiler as a heating facility and oil(diesel, kerosene) and electricity(night thermal-storage power service) as a heating energy. There were a few households using briquette or firewood in a fuel hole with Korean hypocaust. Most of their cooking facilities were gas ranges using LPG. The most popular hot-water supply system was an oil boiler and the next was an electricity boiler. The amount of energy use in a rural household generally showed 20,000 to 40,000 won/month of the electric power rate, 400 to 800 liter/year of the oil and 60 to 120 kg/year of the LPG. Prompt measures should be taken to promote the spread of new and renewable energy such as solar heat, biomass and wind power, etc.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2000년도 제20회 KOSCO SYMPOSIUM 논문집
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• pp.26-34
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• 2000

Geometry change of burner nozzle has influence on fuel atomizing and combustion characteristics. NOx reduction technologies can be divided into two method; Before combustion method(NOx treatment of fuel) and After combustion method(NOx treatment of flue gas). In this study, experiments are carried out using difference nozzle and combustion condition change to reduce NOx in heavy oil fired thermal utility boiler. These methods have advantage like easy application and low installation cost. By this method NOx can be reduced by 18% and maintain CO emission level.

• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 2002년도 Proceedings of the International Welding/Joining Conference-Korea
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• pp.342-348
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• 2002

The welding technology for production of power plant facility as for other industries has been progressing forward automation and mechanization for cost reduction and shortening of cycle time. The welding for boiler tube is automated or mechanized as the parts and subassemblies of tubes are conveyed automatically in the shop. The temperature of boiler stearn is being progressively increased for higher plant efficiency. The welding of nuclear component is characterized by heavy thickness and narrow gap Submerged Arc Welding. Narrow gap Gas Metal Arc Welding and Electron Beam Welding is applied to turbine diaphragm. To improve the resistance of solid particle erosion of turbine blade and nozzle partition, HVOF spray technology and boriding process has been applied.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2006년도 춘계학술대회논문집
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• pp.1034-1039
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• 2006

Large-amplitude, combustion-induced oscillations are observed in most systems involving continuous flow, such as aeroengine afterburners, gas boilers and rocket motors. Strong furnace vibration is typically characterized by the presence of well developed standing waves in the furnace, generating high pressure pulsation and causing structural vibration of the furnace walls. 320MW NG boilers have been experienced high vibration frequently since reconstruction works. Excessive furnace vibration was encountered when a burner air rate is suddenly reduced during load zone changed from 270MW to 300MW. An investigation showed that the primary cause of the vibration was induced by combustion low air flow rate. This paper describes phenomenon examination on strong furnace vibration due to the change of boiler operating conditions.

• 에너지공학
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• 제21권4호
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• pp.385-392
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• 2012

본 연구는 현재 콘덴싱 보일러에 많이 사용하는 다공성 소재중에서 메탈화이버(metal fiber, MF) 및 세라믹(ceramic, CM)으로 제작한 평판형 버너에 대해 연소 및 열특성을 비교 검토하고 그 결과를 향후 개발할 EGR(Exhaust gas recirculation) 콘덴싱 보일러에 적용할 버너 선정의 기초자료로 활용하는 것을 목적으로 한다. CO 배출량은 CM이 MF보다 높았고 NOx 배출량은 MF가 CM보다 높게 나타났다. 버너열량 변화시에는 버너열량이 클수록 효율이 높게 나타났으며 버너 소재별 열효율은 버너열량 변화와 관계없이 MF가 CM보다 높게 나타났다. 본 실험범위에서 KS B 기준과 EN 677기준을 근거로 비례제어, 열효율, CO 및 NOx 배출량을 고려할 때 버너 소재는 MF가 적절하며 당량비는 0.8일때가 최적 운전조건으로 판단된다.