• Journal of Energy Engineering
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• v.15 no.2 s.46
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• pp.83-95
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• 2006

This study is to establish a national vision of the hydrogen economy and design a roadmap to materialize it. A goal is set to supply 15% of final energy consumption with hydrogen energy in Korea by 2040. Selecting the transportation sorter as the main target, more than 50% of vehicles on the road will be replaced with fuel cell vehicles (FCVs) while $20{\sim}30%$ of electricity demand in the residential and commercial sectors might be replaced with power generation by fuel cells. If this goals were attained as planned, primary energy demand would be reduced by 9%, resulting in improved energy mix in which fossil fuel consumption is greatly reduced whereas renewable energy increases by 47%. Furthermore, GHG emissions will be reduced by 20% and self-sufficiency in energy is enhanced up to 23%. If the hydrogen economy is to materialize, the government needs to implement institutional arrangements such as new legislations, organizations, and fiscal measures to facilitate the process. In addition, the private sector's participation is highly recommended to mobilize fund needed for the huge investment to build an infrastructure in preparation for the hydrogen economy. Arrangements for codes and standards are also required to promote industrialization of fuel cells and hydrogen production and consumption.

• Journal of the Korean Institute of Gas
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• v.27 no.3
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• pp.116-122
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• 2023

As the number of hydrogen filling stations for hydrogen supply increases with the progress of low-carbon eco-friendly energy policies, the risk of accidents is also increasing. Actual pressure vessels may have defects such as notches, pores, and inclusions that may occur during the manufacturing process. Therefore, it is necessary to evaluate the integrity of pressure vessels in the case where cracks exist in pressure vessels under internal pressure. In this paper, 3D finite element analysis was used to evaluate the structural safety of hydrogen-filled pressure vessels with surface cracks, and the shape of surface cracks was compared with the commonly used semi-elliptical shape. In the future, these results will be used to predict the remaining life of the pressure vessel in consideration of fracture mechanics.

• Transactions of the Korean hydrogen and new energy society
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• v.20 no.4
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• pp.352-359
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• 2009

KEPRI is developing a Korean type coal-gasification system and the scale is 20 ton/day. Prior to this pilot plant, a 1 ton/day class gasification system will be used for pre-testing of several coal types. This paper introduces the configuration and design conditions of this 1 ton/day class system, presenting the gas/coal ratio, oxygen/coal ratio, cold gas efficiency, CFD analysis of gasifier, and others. The existing combustion furnace for residual oil was retrofitted as a coal gasifier and a vertical and down-flow type burner was manufactured. Ash removal is carried out through a water quencher and a scrubber following the quencher, and the sulfur is removed by adsorption in the activated carbon tower. The gas produced from the gasifier is burned at the flare stack. In this paper, the results of design conditions and initial operation conditions of I ton/day gasification system are compared together.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2009.11a
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• pp.74-77
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• 2009

Ignition performance tests were performed to develop a catalytic ignitor which used hydrogen peroxide and kerosene. Ignition characteristics were investigated by exit area of the catalytic bed, shape of kerosene injector and lead time of purge gas. The results showed that exit area of catalytic bed must be enough for non chocking condition and kerosene must be sprayed with swirl in the middle of catalytic bed. Also in case without preheating of catalytic bed, hydrogen peroxide must be leaded by 3sec, and purge gas must be supplied simultaneously or lately with kerosene.

• Membrane Journal
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• v.33 no.6
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• pp.325-343
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• 2023

Direct methanol fuel cells (DMFCs) have been attracting attention as energy conversion devices that can directly supply methanol liquid fuel without a fuel reforming process. The commercial polymer electrolyte membranes (PEMs) currently applied to DMFC are perfluorosulfonic acid ionomer-based PEMs, which exhibit high proton conductivity and physicochemical stability during the operation. However, problems such as high methanol permeability and environmental pollutants generated during decomposition require the development of PEMs for DMFCs using novel ionomers. Recently, studies have been reported to develop PEMs using hydrocarbon-based ionomers that exhibit low fuel permeability and high physicochemical stability. This review introduces the following studies on hydrocarbon-based PEMs for DMFC applications: 1) synthesis of grafting copolymers that exhibit distinct hydrophilic/hydrophobic phase-separated structure to improve both proton conductivity and methanol selectivity, 2) introduction of cross-linked structure during PEM fabrication to reduce the methanol permeability and improve dimensional stability, and 3) incorporation of organic/inorganic composites or reinforcing substrates to develop reinforced composite membranes showing improved PEM performances and durability.

• Journal of Advanced Marine Engineering and Technology
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• v.35 no.4
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• pp.397-405
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• 2011

Hydrogen energy, as part of eco-friendly alternative energy, is made mostly through reforming of fossil fuels. The turbulent premixed combustion type of metal-fiber flat burner which is recently used in industry was tested in this paper. We measured the mean temperature distributions, CO, HC, $CO_2$ and $O_2$ concentrations to observe the flame structure and flame stability in some kind of experimental conditions. And also PIV and several flow analysis methods were compared to establish the numerical analysis model. The results of this paper will be the basis of the burner design of steam reformer.

• Bulletin of the Korea Photovoltaic Society
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• v.4 no.3
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• pp.36-41
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• 2018

연일 뉴스에 보도되고 있는 미세먼지는 노약자의 호흡기는 물론 발암물질을 포함하고 있어 국민건강에 악영향을 미치기 때문에 반드시 해결되어야 할 사회 문제이다. 미세먼지는 해외 유입 인자와 국내 유발인자를 정확하게 구분하기 어려우나 약 50%의 미세먼지는 2차 발생에 의한 국내 요인으로 발생하고 있는 것으로 파악되고 있으며 화력발전소가 미세먼지 유발 물질의 주요 생성원으로 지목되어왔다. 국내 화력발전소의 50%가 충남 서해안이 위치하고 있어 수도권에 가장 큰 영향을 주는 것으로 밝혀져 충남은 내구연한에 도달한 노후 화력발전소의 폐쇄 및 발전량 감축 조절을 통해 미세먼지 발생을 최소화 하기 위해 노력해왔다. 그러나 태양전지 주도의 신재생에너지 발전으로 전환하는 것만이 미세먼지를 저감시킬 근본적인 해결책이라고 할 수 있다. 충남은 2050년까지 화력발전 비중을 0%로 낮추고 필요한 전력은 에너지컨슈머들이 생산하는 신재생에너지로 생산하는 내용을 골자로 하는 에너지 전환비전을 선포하였다. 이 비전이 선언에 그치지 않고 목표를 달성하기 위해서 이에 대한 세부 이행계획을 수립하고 충남에 맞는 태양광 발전 산업 육성을 위한 정책을 병행해야 할 것이다. 이번 글에서는 충남의 여건을 고려하여 태양광을 이용한 수소 생산 및 인공광합성을 연계한 고부가가치 화학물질의 생산 연구 및 실증 과제를 추진할 것을 제안하였다. 이러한 충남의 노력은 수도권 수요 지역에 대한 전력 공급기지에서 친환경에너지로 유지되는 '청정남도'로서의 재도약을 가능하게 할 것으로 기대된다.

• 한국신재생에너지학회:학술대회논문집
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• 2010.06a
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• pp.106.1-106.1
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• 2010

석탄가스화기술은 매장량이 풍부하여 안정적인 공급이 보장되는 석탄을 이용함과 동시에 환경오염물질 감소라는 사회적 요구조건을 충족시키면서 화학제품, 석탄-가스화, 석탄-디젤화, 연료전지, 복합발전 등 다양한 분야에 응용이 가능한 장점이 있다. 특히 석탄가스화복합기술(Intergrated Coal Gasification Combined Cycle, IGCC)은 석탄을 고온, 고압하에서 가스화시켜 일산화탄소(CO), 수소($H_2$)가 주성분인 합성가스를 제조, 정제 후 가스터빈 및 증기터빈을 복합으로 구동하여 전기를 생산하는 친환경 차세대 발전기술로 주목을 받고 있다. 현재 IGCC 기술은 세계적으로 볼 때 상용화단계에 있고, 우리나라의 경우 한국형 IGCC 기술의 확보를 위한 연구사업이 진행중에 있다. 본 연구는 IGCC 발전플랜트의 발전효율을 결정하는 가장 중요한 부분이라 할 수 있는 가스화반응기의 모델링 기술을 개발하는 목적으로 진행되었다. 본 연구에서는 석탄가스화 반응기에서 발생하는 석탄의 휘발화와 Char의 표면반응 그리고 기상에서의 가스화반응등의 현상을 전산유체역학(Computational Fluid Dynamics)을 이용하여 모델링하는 방법론이 연구되었다. 해석을 위한 형상은 해석에 소요되는 시간을 줄이고, 형상이 해석결과에 미치는 영향을 줄이고자 2차원으로 구성하였다. 해석을 위한 수학적모델으로는 난류모델, 가스화반응모델, Lagrangian particle tracking, Char reaction 등을 포함하였고, 해석을 위한 Solver는 Fluent를 이용하였다. 모델링결과에 의해 예측되는 합성가스의 조성을 상용급 IGCC 가스화기의 운전결과와 비교해 본 결과 본 연구에서 설정한 모델로 예측되는 온도 및 가스농도가 실험치와 유사하게 나타남을 알 수 있었고 이를 통하여 본 연구에서 설정한 모델링방법이 적절함을 알 수 있었다.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.36 no.9
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• pp.971-978
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• 2012

Vacuum carburizing is supposed to be the superior process to the gas carburizing. However, the vacuum carburizing has the stage in which hydrocarbon gas is supplied into the furnace to be pyrolysis, and consequently the stable heat treatment is hard to achieve due to the soot from the hydrocarbon pyrolysis. Recently, many studies have been made which utilize acetylene gas to overcome this defects. In this paper, the carburizing and the diffusion periods have been selected based on the Harris experimental formula, and the mechanical properties of the vacuum carburized specimen have been compared with those of the gas carburized SCM415H specimen to identify the feasibility of the $CO_2$ free vacuum carburizing process. The result showed that the vacuum carburized materials used have no oxidization of the grain boundaries, and show the 29.8% higher effective hardness depth and the acceptable tensile strength.

• The Korean Journal of Petroleum Geology
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• v.4 no.1_2 s.5
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• pp.27-39
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• 1996

In the Cretaceous, the Gulf Coast Basin evolved as a marginal sag basin. Thick clastic and carbonate sequences cover the disturbed and diapirically deformed salt layer. In the Cretaceous the salinities of the Gulf Coast Basin probably matched the Holocene Persian Gulf, as is evidenced by the widespread development of supratidal anhydrite. The major Lower Cretaceous reservoir formations are the Cotton Valley, Hosston, Travis Peak siliciclastics, and Sligo, Trinity (Pine Island, Pearsall, Glen Rose), Edwards, Georgetown/Buda carbonates. Source rocks are down-dip offshore marine shales and marls, and seals are either up-dip shales, dense limestones, or evaporites. During this period, the entire Gulf Basin was a shallow sea which to the end of Cretaceous had been rimmed to the southwest by shallow marine carbonates while fine-grained terrigengus clastics were deposited on the northern and western margins of the basin. The main Upper Cretaceous reservoir groups of the Gulf Coast, which were deposited in the period of a major sea level .rise with the resulting deep water conditions, are Woodbinefruscaloosa sands, Austin chalk and carbonates, Taylor and Navarro sandstones. Source rocks are down-dip offshore shales and seals are up-dip shales. Major trap types of the Lower and Upper Cretaceous include salt-related anticlines from low relief pillows to complex salt diapirs. Growth fault structures with rollover anticlines on downthrown fault blocks are significant Gulf Coast traps. Permeability barriers, up-dip pinch-out sand bodies, and unconformity truncations also play a key role in oil exploration from the Cretaceous Gulf Coast reservoirs. The sedimentary sequences of the major Cretaceous reseuoir rocks are a good match to the regressional phases on the global sea level cuwe, suggesting that the Cretaceous Gulf Coast sedimentary stratigraphy relatively well reflects a response to eustatic sea level change throughout its history. Thus, of the three main factors controlling sedimentation (tectonic subsidence, sediment input, and eustatic sea level change) in the Gulf Coast Basin, sea-level ranks first in the period.