• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2011년도 제37회 추계학술대회논문집
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• pp.717-720
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• 2011

석유자원 고갈, 높은 원유가격 문제 그리고 온실가스인 $CO_2$ 에 의한 지구온난화 문제 때문에 바이오 매스를 이용한 GTL(Gas To Liquid) 공정으로 제조하는 청정 합성연료에 대한 관심이 크게 증가하고 있다. 본 논문에서는 GTL 기술의 3가지 핵심인 천연가스 개질반응, 피셔-트롭스 합성 그리고 물성조절 공정에 관한 기술을 설명하고 각국의 개발현황을 비교하였다.

• 한국에너지공학회:학술대회논문집
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• 한국에너지공학회 2003년도 춘계 학술발표회 논문집
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• pp.595-600
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• 2003

This paper presents the applicability of low caloric synthetic gas from coal gasification to a gas engine system. A commercial LPG engine is modified to use the low caloric synthetic gas from coal gasification as the gas engine fuel. The modification is focused on the fuel supplying system, which includes air flowrate adjusting orifice, gas mixer, vaporizer, preheater, regulators, and fuel tank. The electrical system and others for the alternative fuel are also redesigned and replaced. From the results of engine performance data, we have demonstrated that the engine modified by using coal gasification gas is well operated from idle to wide open throttle conditions although the engine power is somewhat reduced relative to LPG fueled engine. This paper addresses the need to determine the practical potential for such a concept and to identify further research and development efforts that may be necessary.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2013년도 제46회 KOSCO SYMPOSIUM 초록집
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• pp.109-110
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• 2013

This paper describes gas turbine combustion characteristics of synthetic natural gas which contains a small amount hydrogen content. By conducting ambient pressure high temperature combustion test at gas turbine relevant combustor geometry, the combustion characteristics such as combustion instability, NOx and CO emission, temperatures at turbine inlet, nozzle and dump plane, and flame structure from high speed OH chemiluminescence images were investigated when changing hydrogen content from zero to 5%. From the results, qualitative and quantitative relationships are derived between key aspects of combustion performance, notably NOx/CO emission and combustion instability. Natural gas containing hydrogen up to 5% does not show significant difference in view of all combustion characteristics except combustion instability. Only up to 1% hydrogen addition could not change the pressure fluctuation and phase gas between fluctuations of pressure and heat release. From the results, it can be concluded that synthetic national gas which contains 1% of hydrogen can be guaranteed for the stable and reliable operation of natural gas firing gas turbine.

• 신재생에너지
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• 제8권2호
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• pp.24-32
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• 2012

Natural gas hydrates have a high potential as the 21st century new energy resource, because it have a large amount of deposits in many deep-water and permafrost regions of the world widely. Natural gas hydrate is formed by physical binding between water molecule and gas mainly composed of methane, which is captured in the cavities of water molecules under the specific temperature and pressure. $1m^3$ methane hydrate can be decomposed to the methane gas of $172m^3$ and water of $0.8m^3$ at standard condition. Therefore, there are a lot of practical applications such as separation processes, natural gas storage transportation and carbon dioxide sequestration. For the industrial utilization of methane hydrate, it is very important to rapidly manufacture hydrate. However, when methane hydrate is artificially formed, its reaction time may be too long and the gas consumption in water becomes relatively low, because the reaction rate between water and gas is low. So in this study, hydrate formation was experimented by adding natural zeolite and Synthetic zeolite 5A in distilled water, respectively. The results show that when the Synthetic zeolite 5A of 0.01 wt% was, the amount of gas consumed during the formation of methane hydrate was higher than that in the natural zeolite. Also, the natural zeolite and Synthetic zeolite 5A decreased the hydrate formation time to a greater extent than the distilled water at the same subcooling temperature.

• 청정기술
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• 제14권2호
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• pp.117-122
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• 2008

중발열량 석탄 합성가스의 연소 및 NOx 발생 특성에 대한 이론적 해석을 수행하였다. 석탄 합성가스는 CO, $H_2,\;CO_2,\;N_2$가 주성분이고, 미량의 $CH_4$ 및 $NH_3$를 함유하는 것으로 가정하였다. 열화학적 해석을 통해 합성가스 연소 시의 화염 온도, 배기가스의 주요 및 부차적 화학종들의 조성, 열 및 연료 NOx 발생량을 계산하였다. 또한 합성가스 중의 $CH_4$ 및 $NH_3$ 성분이 연소 및 NOx 발생에 미치는 영향을 검토하였다. 본 석탄 합성가스들의 계산결과들을 토대로 가스터빈 연소기의 NOx 저감 설계에 필요한 기본 방향과 기준을 제시하였다.

• Carbon letters
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• 제5권3호
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• pp.133-141
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• 2004

The synthetic behaviors of carbon nanotubes (CNTs) by Fe/MgO catalysts were investigated in 0~90 wt.% range of MgO mixture ratios by catalytic chemical vapor deposition (CCVD) process. The CNTs were synthesized with 40 minutes of synthetic time, and 923 K of synthetic temperature using 0.1 L/min of ethylene gas and 1.0 L/min of hydrogen gas as synthetic and carrier gas, respectively. As the increase of synthetic temperatures and times, the diameters of CNTs become thicker. The carbon yield showed in a parabolic curve as MgO content increased and the maximum carbon yield was obtained at 30 wt.% of MgO. There were no obvious changes in the diameters of CNTs respect to the change of MgO content. Fe/MgO CNTs showed good crystalinity by High Resolution Transmission Electron microscope (HR-TEM) analysis. The behaviors of Fe/MgO CNTs have a tendency of depending on synthetic time and temperature rather than MgO content.

• 한국가스학회지
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• 제10권3호
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• pp.1-6
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• 2006

본 연구는 석탄을 가스화한 저발열량 합성가스 연료의 가스엔진과 소형가스발전기로의 적용가능성을 보여준다. 석탄을 가스화한 저발열량 합성가스를 가스엔진의 연료로 사용하기 위해 상용 LPG엔진을 부분적으로 변경하였다. 석탄가스화 연료에 적합한 연료공급시스템 -공기유량조절 오리피스, 가스믹서, 기화기, 예열히터, 레귤레이터, 연료탱크-이 집중적으로 변경되었다. 엔진 운전 결과에서 비록 석탄가스화 연료의 엔진 출력이 LPG연료에 비해 다소 떨어지지만 석탄가스화 연료를 사용하는 엔진이 공회전 조건에서부터 교축밸브를 완전 개방한 전부하조건까지 잘 운전됨을 보여주었다. 또한 본 연구에서 개발된 가스엔진발전기는 다양한 부하에서도 잘 작동됨을 보여주었다.

• Environmental Engineering Research
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• 제17권3호
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• pp.157-165
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• 2012

This experimental study was performed to obtain thermal energy from the combustion of synthetic gas, produced by the pyrolysis of insulating oil containing polychlorinated biphenyls (PCBs) in a high temperature and high pressure reactor. The average synthetic gas generated was $59.67Am^3/hr$ via the steady state gasification of insulating oil waste (20 kg/hr) with average concentrations (standard deviation) of $CO_2$, CO, and $H_2$ in the synthetic gas of $38.63{\pm}3.11%$, $35.18{\pm}1.93%$, and $28.42{\pm}1.68%$, respectively. The concentrations of the PCBs in the transformer insulating oil and synthetic gas after its gasification, and the concentrations of the dioxins that could be produced from the incomplete degradation of PCBs were measured. It was revealed that the PCBs in the insulating oil were composed of the series from tetrachlorobiphenyl to octachlorobiphenyl. However, only the #49, #44, #52, and #47/75/48 congeners were detected from the synthetic gas after gasification of the insulating oil and in the flue gas from the combustor. In conclusion, the experimental conditions suggested in this study were very useful for the appropriate treatment of insulating oil containing PCBs. Also, fuel gas containing CO and $H_2$ can be obtained from the pyrolysis of insulating oil containing PCBs.

• 한국가스학회지
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• 제22권2호
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• pp.67-71
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• 2018

메탄을 주성분으로 하는 일반적인 합성천연가스의 열량은 $9,300kcal/m^3$ 이하이며, 이러한 합성천연가스를 국내에서 도시가스로 사용하기 위해서는 $10,200kcal/m^3$로의 증열이 필요하다. 일반적으로, 합성천연가스의 열량조절에는 프로판가스를 상용하나, 가격의 변동폭이 크고 대체로 합성천연가스의 제조원가보다 비싸왔다. 그러므로 프로판을 통한 증열 대신 고열량의 합성천연가스를 직접 생산할 수 있다면, 합성천연가스의 생산가격을 상당히 감소시킬 수 있다. 본 논문에서는 미국 NETL 분석 자료를 기반으로, 메탄이 주성분인 합성천연가스의 제조 및 증열과 고열량 합성천연가스의 직접 제조 시의 원가를 비교분석하였다.

• 한국자동차공학회논문집
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• 제16권3호
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• pp.94-101
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• 2008

Since regulations of exhaust emissions are continuously reinforced, studies to reduce harmful emissions during the cold start period of SI engines have been carried out very extensively worldwide. During the cold start period, raising the temperature of cold exhaust gas is a key strategy to minimize the light-off time of three way catalysts. In this study, a synthetic gas containing a large amount of hydrogen was injected into the exhaust manifold to raise the exhaust gas temperature and to reduce harmful emissions. The authors tried to evaluate changes in exhaust gas temperature and harmful emissions through controlling the engine operating parameters such as ignition timings and lambda values. Also the authors investigated both combustion stability and reduction of harmful emissions. Experimental results showed that combustion of the synthetic gas in the exhaust manifold is a very effective way for solving the problems of harmful emissions and light-off time. The results also showed that the strategy of retarded ignition timings and increased air/fuel ratios with ESGI is effective in raising exhaust gas temperature and reducing harmful emissions. Futhermore, the results showed that engine operating parameters ought to be controlled to lambda = 1.2 and ignition timing = $0{\sim}3^{\circ}$ conditions to reduce harmful emissions effectively under stable combustion conditions.