• Journal of Advanced Marine Engineering and Technology
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• 제37권2호
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• pp.236-241
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• 2013

처음 승선한 실습 기관사가 선박 기기에 대한 다양한 경험을 쌓고 비상시에 대비할 수 있을 정도의 수준에 도달하려면 긴 시일과 많은 비용이 든다. 따라서 현장과 유사한 환경에서 짧은 시간내 체계적인 교육과 훈련을 통해 다양한 경험과 비상시 적절한 판단을 가능케 하도록 STCW-95 권고안을 따르는 여러 형태의 시뮬레이터가 개발되어 교육 훈련 도구로써 활용되고 있다. 현재 국내에서 운용되고 있는 기관시뮬레이터는 전량 외국에서 도입된 것으로서 국제협약의 개정이나 기술발전사항 등을 바로 반영하기 힘든 상황이다. 본 연구에서는 실습기관사가 보조 보일러, 배기 보일러 및 증기터빈과 같은 증기계통의 각종 장치간의 연관성을 쉽게 파악할 수 있도록 하는 선박용 보조 보일러 시뮬레이터 개발에 대하여 논한다.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2013년도 제46회 KOSCO SYMPOSIUM 초록집
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• pp.1-3
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• 2013

The premixed combustion system applying exhaust gas recirculation was investigated to achieve the low pollutant emission and the high thermal efficiency. In this study, it was studied the effects of EGR on the thermal efficiency, $NO_x$ and CO emissions with various EGR ratios and equivalence ratios. As results, when equivalence ratio was increased, thermal efficiency increased and $NO_x$ and CO concentration increased. When EGR was applied, $NO_x$ and CO concentration decreased and thermal efficiency increased. Especially, in the case of 15% of EGR ratio at 0.85 of equivalence ratio, $NO_x$ and CO concentration will be a smaller than these of a current operating condition of the boiler and thermal efficiency was about 1.7% higher.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 2000년도 THE THIRD INTERNATIONAL CONFERENCE ON AGRICULTURAL MACHINERY ENGINEERING. V.III
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• pp.639-646
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• 2000

Hot air heater with light oil combustion is the most common heater for greenhouse heating in the winter season in Korea. However, since the heat efficiency of the heater is about 80%, considerable unused heat in the form of exhaust gas heat discharges to atmosphere. In order to capture this exhaust gas heat a heat recovery system for plant bed heating in the greenhouse was built and tested in the hot air heating system of greenhouse. The system consists of a heat exchanger made of copper pipes, ${\phi}\;12.7{\times}0.7t$ located inside the rectangular column of $330{\times}330{\times}900mm$, a water circulation pump, circulation plastic pipe and a water tame The total heat exchanger area is $1.5m^2$, calculated considering the heat exchange amount between flue gas and water circulated in the copper pipes. The system was attached to the exhaust gas path. The heat recovery system was designed as to even recapture the latent heat of flue gas when exposing to low temperature water in the heat exchanger. According to performance test it can recover 45,200 to 51,000kJ/hr depending on the water circulation rates of 330 to $690{\ell}$/hr from the waste heat discharged. The exhaust gas temperature left from the heat exchanger dropped to $100^{circ}C$ from $270^{circ}C$ by the heat exchange between the water and the flue gas, while water gained the difference and temperature increased to $38^{circ}C$ from $21^{circ}C$ at the water flow rate of $690{\ell}$/hr. And, the condensed water amount varies from 16 to $43m{\ell}$ at the same water circulation rates. This condensing heat recovery system can reduce boiler fuel consumption amount in a day by 34% according to the feasibility study of the actual mimitomato greenhouse. No combustion load was observed in the hot air heater.

• 대한기계학회논문집B
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• 제23권9호
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• pp.1085-1097
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• 1999

A separate heat pipe system capacity of 3,700kW has been developed and applied to preheating the blast furnace gas for recovery of the waste heat from boiler. The system is designed to preheat the blast furnace gas up to $126^{\circ}C$ by using tho boiler exhaust gas of which temperature is $180^{\circ}C{\sim}220^{\circ}C$. The arrangement of the fin tubes as well as the shape of the fin has been carefully determined to minimize the fouling problems. The heat pipe system was found to be stable in circulation of the working fluid and the range of the temperature variation of the preheated blast furnace gas was within $10^{\circ}C$. It was proved through a long-term test that the selected tube arrangement and the shape of the fins are proper to prevent the fouling problems and that the pay-back period of the system Is within one year.

• 한국분무공학회지
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• 제28권1호
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• pp.43-48
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• 2023

The waste-heat-recovery boiler with water spray (HR-B/WS) applies the heat exchange between the inlet air and exhaust gas with the water spray into the inlet air. The evaporation of water in the inlet air promotes heat recovery from the exhaust gas so that thermal efficiency can be improved by the enhanced condensing effect. The NOx emission can also be reduced by lowering the flame temperature due to the dilution effect of the water. In this study, the validity of this concept is examined by the practical boiler test performed with a 24 kW condensing boiler under the full load condition according to the water injection amount. The theoretical amount of water injection is calculated under the assumption of full evaporation of the sprayed water, which is calculated as 50 g/min. Since the injected water cannot evaporate fully in the actual system, the maximum water spray amount is set as 100 g/min. The results showed that the water injection can increase the thermal efficiency up to 95.59% and reduce NOx and CO emissions simultaneously to 8.9 ppm and 35 ppm at 0% of O₂. Although the heat energy loss increased due to the unevaporated water, the increase in water injection amount caused higher thermal efficiency due to the increased amount of the evaporated water.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2009년도 추계학술발표대회 논문집
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• pp.259-264
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• 2009

Most of the fossil power plants firing lower grade coals are challenged with maintaining good combustion conditions while maximizing generation and minimizing emissions. In many cases significant derate, availability losses and increase in unburned carbon levels can be attributed to poor combustion conditions as a result of poorly controlled local fuel and air distribution within the boiler furnace. The poor combustion conditions are directly related to the gas flow deviation in upper furnace and convection tube-bank but a less reported issue related to in large-scale oppose wall fired boilers. In order to develop a on-line combustion monitoring system and suggest an alternative heat flux estimation method at tube bank, which is very useful information for boiler design tool and blower optimizing system, field test was conducted at operating power boiler. During the field test the exhaust gases' temperature and tube metal temperature were monitored by using a spatially distributed sensors grid which located in the boiler's high temperature vestibule region. At these locations. the flue gas flow is still significantly stratified, and air in-leakage is minimal which enables tracing of poor combustion zones to specific burners and over-fire air ports. Test results showed that the flue gas monitoring method is more proper than metal temperature distribution monitoring for real time combustion monitoring because tube metal temp. distribution monitoring method is related to so many variables such as flue gas, internal flow unbalance, spray etc., Heat flux estimation at the tube bank with flue gas temp. and metal temp. data can be alternative method when tube drilling type sensor can't able to use.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2015년도 제51회 KOSCO SYMPOSIUM 초록집
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• pp.201-204
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• 2015

Recently, energy excessive consumption and environmental pollution are the social issued. The most efficient way to solve both energy excessive consumption and environmental pollution is existing combustion system improved. This study was part of the assume and commercial used existing waste heat recovery condensing boiler to low emission performance for exhaust gas recirculation(EGR) and thermal efficiency rise by applying the condensed water recirculation(CWR) conducted. The researchers applied the EGR and CWR develop a new concept for the condensed water recirculation waste heat recovery condensing boiler. Waste heat recovery condensing boiler applied to the condensed water recirculation thermal efficiency of the same conditions was increased by about 4.8~5.5% and pollution emission also decreased.

• 유기물자원화
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• 제14권3호
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• pp.85-90
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• 2006

플라즈마 용융로에 설치된 폐열 보일러를 실측치와 근접한 모의 보일러를 설계하여 CFD(전산유체역학) 프로그램을 이용하여 얻어진 보일러 내에서의 유해가스발생 및 열 유동현상에 대한 열 설계 능력 확보와 폐열보일러 효율 개선에 대한 연구를 수행하는데 목적이 있다. 보일러 내에서의 온도변화 및 연소가스의 공기 유동, 부식성 가스의 영향으로 인해 보일러 내부에서의 부식위치 및 클링커 생성여부에 관한 연구를 통해 효율적인 보일러의 구조 설계 및 에너지 재활용방안에 이용하고자 한다. 연구결과 플라즈마 용융로에 설치된 보일러 설비는 2차 연소로 출구에서 배출되는 약 $1,200^{\circ}C$의 연소가스를 약 $450^{\circ}C$까지 냉각시킬 수 있는 설계조건을 만족시켰다. 반면 유해가스 유동 결과 보일러 입구 부분의 상단부와 하단부에 부식성 가스 (SOx, HCl)의 영향으로 인하여 부식 및 클링커 생성이 보일러의 다른 위치보다 쉽게 발생될 것으로 예상된다. 이로 인해 보일러 내 외관벽의 부식으로 보일러의 수명 단축 및 효율적인 폐열을 재활용 할 수 없다고 예상된다. 이에 따른 저온 및 고온 부식 방지대책에 대한 세심한 고려가 필요하다 하겠다.

• 한국가스학회지
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• 제7권4호
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• pp.7-13
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• 2003

본 연구에서는 연소가스의 잠열을 활용함으로서 에너지를 절약하고 배기가스 속의 오염 물질을 저감할 수 있는 콘덴싱 가스보일러의 예혼합버너와 열교환기를 최적화하기 위한 실험을 수행하였다. 본 연구에서 사용된 가스보일러의 열교환기는 상부, 하부 및 코일 열교환기 3개부분으로 구성되어 있다. 상부 열교환기는 예혼합버너를 둘러싸고 있으며 하부 열교환기는 상부열교환기 하단에 설치되어 있다. 그리고, 코일형 열교환기는 상부와 하부열교환기의 바깥 표면을 감싸고 있는 구조로 되어 있다. 본 연구를 통하여 설계된 보일러의 TDR은 당량비 0.75${\~}$0.80 부근에서 약 4:1이며 열효율이 $97\%$로 나타났다. 또한, NOx 및 CO 배출농도는 당량비 0.8 부근에서 각각 20ppm과 140ppm의 낮은 수치를 보였으며 버너의 직경을 기존의 60mm에서 50mm로 변경한 결과, CO의 배출농도가 50ppm까지 현저히 낮아짐을 알 수 있었다.

• 한국수소및신에너지학회논문집
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• 제34권1호
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• pp.38-46
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• 2023

Carbon neutrality policies have been strengthened to reduce emissions, and the importance of technology road maps has been emphasized. In the global industrial boiler market, carbon neutrality is implemented through fuel diversification of methane-hydrogen mixture gas. However, various problems such as flashback and flame unstability arise. There is a limit to implementing the actual system as it remains in the early stage. Therefore, it is necessary to secure the source technology of methane-hydrogen hybrid combustion system applicable to industrial fields. In this study, control program for methane-hydrogen fuel conversion was developed to expect various parameters. After determining the hydrogen mixing ratio and the input air flow, the fuel conversion control algorithm was constructed to get the parameters that achieve the target oxygen concentration in the exhaust gas. LabVIEW program was used to derive correlations among hydrogen mixing rate, oxygen concentration in exhaust gas, input amount of air and heating value.