• Proceedings of the KSME Conference
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• 2001.11b
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• pp.177-184
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• 2001

Combustion using oxygen enriched air is an energy saving technology that can increase thermal efficiency by the improvement of burning rate and high temperature flame. But information about it is not so enough yet. Flame figure, temperature distribution and emission concentration were measured with oxygen enriched concentration and swirl number in a turbulent diffusion flame to investigate the combustion characteristics. The results showed that flame figure became different as long as oxygen enriched concentration varied and that concentration of NO increased suddenly around $O_2$ 60%.

• Journal of Advanced Marine Engineering and Technology
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• v.27 no.7
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• pp.845-851
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• 2003

The purpose of this experimental study is to investigate the quantitative pollutants reduction by oxygen enrichment and induced air effect in venturi type after-burner. For this purpose, CO, $CO_2$, $O_2$. and HC concentrations were measured before and after the after-burner by changing the Oxygen flow rate and area ratio which is defined as the ratio of air inducing area divided by total area. As results of this study, when the area ratio were increased, the emission reduction effect was increased even less oxygen flow rate. In that case when oxygen was injected too little, the pollutants were increased.

• Proceedings of the Korean Nuclear Society Conference
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• 2001.10a
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• pp.290.1-290
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• 2001

• Transactions of the Korean Society of Mechanical Engineers B
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• v.28 no.1
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• pp.9-15
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• 2004

$CO_2$ is a well-known green house gas as well as the major source of global warming. Many researchers have studied to reduce $CO_2$ emission in combustion processes. Among the method for reducing $CO_2$ emission, oxygen-enriched combustion has been proposed. Because its adiabatic flame temperature is relatively too high, existing facilities must be changed or the flame temperature in the combustion zone should be reduced. The combustion characteristics, composition in the flame zone, temperature profile and emission gases were investigated experimentally for the various oxygen-enriched ratios(OER) by the addition of $CO_2$, under constant $O_2$ flow rate. Results showed that the reaction zone was quenched and broadened as the addition of $CO_2$ was increased. The emission of NOx in flue gas was decreased as decreasing temperature in reaction zone. It was also shown that the reaction was delayed by the cooling effect. As the addition of $CO_2$ was increased, the composition of CO in the flame zone was increased due to the increase of reaction rate by increasing mixing effect of oxidant/fuel at OER=0％, but the composition of CO was decreased by quenching effect at OER=50％ and 100％.

• Proceedings of the KSME Conference
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• 2003.04a
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• pp.1389-1394
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• 2003

$CO_2$ is a well-known green house gas, which is the major source of global warming. Many researchers have studied to reduce $CO_2$ emission in combustion processes. Among the method for reducing $CO_2$ emission, oxygen-enriched combustion has been proposed. But the adiabatic flame temperature is too high. So existing facilities must be changed, or the adiabatic flame temperature in the combustion zone should be reduced. The combustion characteristics, composition in the flame zone, temperature profile and emission gases were studied experimentally for the various oxygen-enriched mtios(OER) by addition of $CO_2$ under coustant $O_2$ flowrate. Results showed that the reaction zone was quenched, broadened, as addition of $CO_2$ was increased. Temperature has a large effect on the NOx emission. The emission of NOx in flue gas decreased due to the decreased temperature of reaction zone. It was also shown that the reaction was delayed by the cooling effect. As the addition of $CO_2$ was increased, the composition of CO in the flame zone increased due to the increase of reaction rate by increasing mixing effect of oxidant/fuel at OER=0, but the composition of CO decreased by quenching effect at OER=50 and 100%.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.05a
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• pp.239-240
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• 2000

용존산소는 양식 시설 내 생산량을 결정짓는 중요한 수질 조건으로서, 시설 내 용존산소를 충분히 공급하기 위해 많은 연구자들이 여러 가지 형태의 에어레이터의 고안(Boyd and Tucker, 1979)및 순수산소의 이용에 관해 연구해왔다. 그러나 에어레이터 또는 순수 산소의 이용은 추가 에너지가 필요한데, 송어 양식장에는 전체비용의 13∼15%, 부화장의 경우에는 23%(Petit, 1990) 및 순환여과식 시설에서는 8.6%(Timmons and Aho, 1998)의 경비가 추가된다고 한다. (중략)

• Transactions of the Korean Society of Mechanical Engineers B
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• v.28 no.2
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• pp.160-166
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• 2004

Combustion using oxygen enriched air is known as a technology which can increase flame stability as well as thermal efficiency due to improving the burning rate. Lift-off, blowout limit and flame length were examined as a function of jet velocity, coflow velocity and OEC(Oxygen Enriched Concentration). Blowout limit of the flame below OEC 25% decreased with increase of coflow velocity, but the limit above OEC 25% increased inversely. Lift-off height decreased with increase of OEC. In particular, lift-off hardly occurred in the condition above OEC 40%. Flame length of the flames above OEC 40% was increased until the blowout occurred. Great flame stability was obtained since lift-off and blowout limit significantly increased with increase of OEC.

• Proceedings of the KSME Conference
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• 2003.11a
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• pp.326-331
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• 2003

Combustion using oxygen enriched air is known as a technology which can increase flame stability as well as thermal efficiency due to improvement of the burning rate. Lift-off, blowout limit and flame length were examined as a function of jet velocity, coflow velocity and OEC(Oxygen Enriched Concentration). Blowout limit of the flame below OEC 25% decreased with coflow velocity, but the limit above OEC 25% increased inversely. Lift-off height decreased with increase of OEC. Especially lift-off hardly occurred in the condition above OEC 40%. Flame length of the flames above OEC 40% was increased until the blowout occurred. Flame stability became improved since lift-off and blowout limit increased much with increase of OEC.

• Journal of the Korean Institute of Gas
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• v.11 no.4
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• pp.17-22
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• 2007

The NOx emission characteristics with oxygen enrichment in non-premixed counterflow flames were investigated numerically. To consider systematically the situation of inevitable $N_2$ contamination by air infiltration in the process of pure-oxygen combustion, the volume ratio of $O_2$ in an oxidizer was changed from 21% to 100%. As a result the NO emission index $(EI_{NO})$ has the highest value under condition of 75% oxygen enrichment. This result can be explained by the change of $N_2$ destruction rate with oxygen enrichment rather than flame temperature, flame thickness and residence time. In particular, it was found that the reaction of N+NO=$N_2+O$ has the largest contribution on NOx production in oxygen-enrichment flames.

• Proceedings of the Membrane Society of Korea Conference
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• 1997.10a
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• pp.21-24
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• 1997

1.서론 : 산소선택성이 좋은 투과막은 산소부화에 의한 연소효율의 향상, 간이 산소발생장치에의 응용 등 여러가지의 용도가 예상된다. 이를 위한 준비단계로 막소재 및 막형상에 대한 검토가 \ulcorner발하게 진행되고 있다. 그 중에서 높은 산소선택성을 발현하는 방법이 주목되어지고 있는데 이는 가역적 산소흡탈착능을 갖는 carrier분자를 이용한 촉지운송계(facilitated transport system)를 구축하는 방법이 있다. 본 연구에서는 [Co(salen)]과 같은 $N_2O_2$형 평면정방착제(Square planar complex)이며, salen의 shift염기부분을 bipyridine cycle, phenoxide부분을 해리한 amide로 골격변환한 구조를 갖고 있는 6,6'-bis(benzoylamino)-2,2'-bipyridine(babpH$_2$)의 covalt착체([Co(babp)]를 배위결합에 의해 고분자막중에 고정하고, 산소흡탈착능, 산소투과성, 안정성 등을 검토하는 것을 바탕으로 우수한 선택성 산소투과막을 개발하는 것을 목적으로 한다.