• Transactions of the Korean Society of Mechanical Engineers B
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• v.25 no.2
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• pp.244-251
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• 2001

This paper describes a design study of heat exchanger assembly to be used for low NOx condensing gas boiler. In this study, specifications of each heat exchanger components(upper and lower fin-type HEX, coil-type HEX, baffle) were investigated experimently by using model apparatus and analytical model, and comprehensive performances of the pilot gas boiler were examined. As a result, the boiler efficiency for heating and hot-water reached 90% and 94%, respectively. NOx and CO emission are less than 50ppm and 200ppm (0$_2$0% basis), respectively, which are very improved results than those of conventional bunsen-type boiler. But it is considered that supplementary investigations necessary for CO emission improvement and optimum design with boiler capacity.

• Journal of Energy Engineering
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• v.9 no.2
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• pp.109-116
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• 2000

저발열량 석탄가스의 thermal/fuel NOx 생성특성과 화염 안정성을 규명하기 위한 실험적 연구를 수행하였다. 저발열량 합성 연료 가스는 일산화탄소, 수소, 질소 및 암모니아를 천연가스 연료와 동일한 입열량을 가지도록 혼합하여 만들었고 , 합성가스는 평면 화염 버너를 공급하여 태웠다. 특정한 합성가스에 대해 당량비를 변화시켜 가며, 비화 또는 역화에 의한 화염안정성을 규명하였고 안정된 화염 영역을 정의하였다. 저발열향 합성가스의 연소시 발생하는 thermal 및 fuel NOx를 측정하여 천연가스 연소시의 경우와 비교하였다.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 2001.11a
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• pp.105-108
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• 2001

• Proceedings of the KSME Conference
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• 2004.11a
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• pp.1751-1755
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• 2004

Increasing environmental pressures to reduce NOx emission are being placed on coal-fired boilers. To meet the environmental requirements, Doosan Heavy Industries & Construction Co., Ltd.(Doosan) has developed low NOx pulverized coal burner. Low NOx pulverized coal burner has already delivered, and it's combustion performance was evaluated to the NOx and Unburned Carbon(UBC) during the commissioning tests. The test results are shown that the strong relationship is existed between NOx and OFA flow rate, and also fuel-N fraction of coal has effected on NOx emission.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 1999.10a
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• pp.473-474
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• 1999

일반적으로 NOx배출은 연소과정에 의해 강력하게 지배되고 있으며, NOx 저감 기술은 1970년대 후반부터 많은 연구들이 수행되어, 그 이론들이 확립되고 있다. 석탄 연소시스템에서는 공기 다단(air staging, OFA), 연료다단(fuel staging, reburning) 및 배기가스 재순환(FGR) 등이 대표적인 NOx 저감 기술이며 [1∼4], 그 중 배기가스 재순환법은 저산소 배기가스를 연소용 공기에 재혼입시키므로써 NO의 생성속도를 저하시켜 NOx를 저감시키는 기법이다.(중략)

• Journal of the Korean Society of Combustion
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• v.14 no.1
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• pp.19-24
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• 2009

A novel low NOx oil burner of 0.7 MW (for a 1 ton steam/hr industrial boiler) was designed and tested to investigate the combustion characteristics through in-flame measurement and flue gas analysis. Flame shape was observed by CCD camera and $CH^*/{C_2}^*$ radical distribution in the flame were observed, along with measurement of flue gas composition such as NOx and CO, for various heat inputs, excess airs and pressure of the fuel spary nozzles. The flame showed the two-zone structure: fuel-rich and fuel-lean zone, which was very favorable for the low-NOx combustion, and the NOx emission for haevy oil combustion was significantly reduced to < 150 ppm at 4 % $O_2$, compared with the NOx level of a conventional heavy oil burner.

• 한국연소학회:학술대회논문집
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• 2003.12a
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• pp.65-74
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• 2003

Air pollution included Nitric Oxide(NOx) from heating boilers is increased by pursuing better life. Development of low NOx emission boiler is strongly needed. However commercial burner for heating boiler is also asked to be thermal efficient and low-cost manufactuable in addition to low NOx emission. Small space for combustor including burner is usually allowed. In this study, parametric study of compact low NOx burner for heating boiler was done using numerical analysis and experiments. Commerical computational fluid dynamic(CFD) program named CFX 5-6 was used for numerical analysis of low NOx burner using turbulent diffusion flame. Comparison of outlet NO and outlet temperature under various equivalence ratio and fuel flow rate was performed between experiment and numerical analysis.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.14 no.11
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• pp.931-938
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• 2002

Combustion dynamics of a dry low NOx gas turbine have been measured by utilizing a dynamic pressure measurement system. The software part of the measurement system, implemented with a commercial general-purpose DASYLab version 5.6 code, basically acquires combustion dynamics signals, performs the FFT analysis, and displays the results. The gas turbine often experiences momentary combustion instability, especially when its combustion mode changes. It is found that the measurement system developed in the study may outperform the other commercial dynamic pressure measurement system. The developed system currently serves to monitor the combustion dynamics of the gas turbine.

• Transactions of the Korean hydrogen and new energy society
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• v.22 no.6
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• pp.934-941
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• 2011

Characteristics of low NOx burner is investigated. Low NOx burner introduced in this paper adopts two staged combustion with plasma burner for the 1st stage combustion. Extensive parametric tests were done to figure out the effect of burner stoichiometry, staged thermal load, electric power for plasma generation. Overall NOx production by burner shows effective reduction by adopting plasma staged burner. and the aspects depends on the fuel stoichiometry of 1st stage burner or operating condition of plasma burner. It is promising to use plasma burner as an alternative tools of low NOx burner technology.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 1999.05a
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• pp.89-93
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• 1999

Experimental studies are conducted to investigate the flame stability and the thermal/fuel NOx formation characteristics of the low calorific value(LCV) gas fuel. Synthetic LCV fuel gas is produced through mixing carbon monoxide, hydrogen, nitrogen and ammonia on the basis that the thermal input of the syngas fuel into a burner is identical to that of natural gas, and then the syngas mixture is fed to and burnt with air on flat flame burner. Flame behaviors are observed to identify flame instability due to blow-off or flash-back when burning the LCV fuel gas at various equivalence ratio conditions. Measurements of NOx in combustion gas are made for comparing thermal and fuel NOx emissions from the LCV syngas combustion with those of the natural gas one, and for analyzing ammonia to NOx conversion mechanism. In addition, the nitrogen dilution of the LCV syngas is preliminarily attempted as a NOx reduction technique.