• 한국추진공학회지
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• 제22권2호
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• pp.74-86
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• 2018

본 연구에서는 수소발생기에 대한 일차원 모델링을 수행하였다. 본 연구에서 고려하고 있는 수소발생기에서 알칼리용액은 위로부터 건조한 알루미늄 파우더로 공급되며, 알칼리용액이 아래방향으로 진행함에 따라 알루미늄과 반응하여 수소가 발생한다. 수소기체와 알칼리용액에 대한 화학종보존방정식과 기체-액체-고체 혼합물에 대한 에너지보존방정식을 고려하였으며, 기체의 상승속도와 액체의 하강속도는 이론적인 접근법을 이용하여 고려하였다. 개발된 프로그램은 수소발생량 및 수소포집기압력과 비교하여 검증한다. 또한, 개발된 프로그램은 농도, 부피분율, 온도 등 반응대의 내부 물성변화를 성공적으로 예측하였으며, 이는 혁신적인 수소발생기의 설계에 많은 도움을 줄 수 있을 것으로 사료된다.

• 한국재료학회지
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• 제26권5호
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• pp.241-245
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• 2016

Hydrogen is considered a potential future energy source. Among other applications of hydrogen, hydrogen-rich water is emerging as a new health care product in industrial areas. Water electrolysis is typically used to generate a hydrogen rich water system. We annealed 10AA carbon paper in air to use it as an electrode of a hydrogen rich water generator. Driven by annealing, structural changes of the carbon paper were identified by secondary electron microscope analysis. Depending on the various annealing temperatures, changes of the hydrophilic characteristics were demonstrated. The crystal structures of pristine and heat-treated carbon paper were characterized by X-ray diffraction. Improvement of the efficiency of the electrochemical oxygen evolution reaction was measured via linear voltammetry. The optimized annealing temperature of 10AA carbon paper showed the possibility of using this material as an effective hydrogen rich water generator.

• 한국항공우주학회지
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• 제39권7호
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• pp.627-633
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• 2011

연료전지 무인기 탑재용 수소발생기의 온도환경변화에 따른 성능평가를 수행하였다. 수소 저장 및 발생을 위해 화학수소화물 중 수소함량이 높고 저장성이 우수한 수소화붕소나트륨($NaBH_4$)을 연료로 사용하였으며, 촉매를 이용한 가수분해반응을 통해 수소를 발생하였다. 수소발생기의 온도환경변화를 위한 저온 및 고온 챔버를 각각 준비하였으며, 온도범위는 $-20^{\circ}C$에서 $60^{\circ}C$까지 $20^{\circ}C$의 간격으로 설정하였다. 20과 25wt.%의 $NaBH_4$ 용액 농도에서 수소발생기의 수소발생률과 반응기와 분리기의 온도변화를 측정하였다. 수소 발생률은 반응주기가 반복될수록 감소하였으며, 저온 환경에서는 높은 수소발생률을 보였지만, 고온 환경에서는 수소발생률이 급격히 감소하였다. 수소발생률의 감소는 촉매유실과 촉매표면의 $NaBO_2$ 도포가 원인으로 확인되었다.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2011년도 제37회 추계학술대회논문집
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• pp.317-320
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• 2011

과산화수소와 케로신을 이용한 이원액체추진제 로켓엔진을 위한 산화제 터보펌프를 설계하였으며 수류시험을 통해 설계된 터보펌프의 작동여부를 실험하였다. 과산화수소 터보펌프의 설계조건을 결정하고 펌프의 임펠러를 설계하였다. 펌프를 구동하기 위한 터빈을 차량용 터보차저로 선정하였으며 터빈 맵을 이용하여 가스발생기를 설계하였다. 펌프, 터빈과 가스발생기를 통합하여 터보펌프 시스템을 구축하였으며 수류시험을 통해 터보펌프 시스템이 1.47 bar의 압력으로 3.4 kg/s의 유량을 공급하는 것을 확인하였다.

• 한국전기전자재료학회논문지
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• 제26권7호
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• pp.563-566
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• 2013

We investigated the variation of anion exchange membrane of hydrogen generator of alkaline electrolysis. We detected the variation of elements and change of anion exchange membrane using EDS and FE-SEM. We detected two different sites of membrane because of different structure of membrane. $Sp_1$ shows that the distribution ratio of C, O, Al is 98% very higher than $Sp_2$ of 78%. Especially, the main elements of STS316 which is P, S, Fe, Ni were more detected at $Sp_2$ than $Sp_1$. We think that this result depends on the structure of membrane. This also affect the resistance, lifetime of membrane and decrease the efficiency of hydrogen production. We hope that this article is a foundation of developing of hydrogen production technology.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 추계학술대회 논문집 학회본부 A
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• pp.442-445
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• 1999

In this work, to detect of hydrogen in DI water in the generator area of nuclear power plants was fabricated Pd/Pt gate MISFET sensor using Pd membrane. $H_2$ permeation through Pd accounts for external mass transfer, surface adsorption and desorption, transitions to and from the bulk metal, and diffusion within the metal. The identification of pinholes in the generator area of plant is an important safety consideration, as hydrogen build-up gives rise to explosion. For this type of application the sensor needs to be isolated in DI water, accordingly, a Pd membrane was used to separate the DI water. The hydrogen in the DI water was then absorbed on the Pd thin film and diffused into the oil through the thin film. The Pd/Pt gate MISFET sensor, encapsulated by oil, will thereby detect permeated hydrogen.

• 한국전기전자재료학회논문지
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• 제26권7호
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• pp.522-527
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• 2013

In this paper, We studied the change of surface and variation of elements on both electrodes of hydrogen generator of alkaline electrolysis in use of FE-SEM and SIMS. We used the stainless steel 316(600 ${\mu}m$) as electrode in condition of 25%KOH, $60^{\circ}C$ Temperature. The results show that the intensity of elements (C, Si, P, S, Ti, Cr, Mn, Fe, Ni, Mo) of Positive Electrode are decreased as much as about $10^1{\sim}10^3 $than the original electrode. Thickness of Positive Electrode is decreased about 40 ${\mu}m$ after chemical reaction. The negative electrode, however, shows a slight variation in the intensity of elements (C, Si, P, Fe, Ni, Mn, Mo) but Change of thickness and surface' shape of electrode show nothing after chemical reaction. The change in thickness and variation of Stainless Steel 316 cause the lifetime of electrode to be shorted. We also observed hydrogen, oxygen, potassium in both electrodes. Especially, The potassium is increased in proportional with depth of positive electrode. this means the concentration of alkali solutions is changed. and so we have to supply alkaline solution to generator in order to produce same quantity of hydrogen gas continuously. we hope that this study gives a foundation to develop the electrode for hydrogen generator of alkaline electrolysis.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2005년도 춘계학술대회논문집
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• pp.385-390
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• 2005

This paper provided a counter measures against the troubles and accidents that are likely to take place in the power plant using hydrogen gas as a coolant for the cooling system of the generator. Because of the extremely wide flammability limits of hydrogen in comparison to the other flammable gases, the safety measures against the hydrogen accidents is very important to ensure the normal operation of electric-power facility. This study's purpose was a presentation of standard model of safety management of hydrogen equipments in the coal firing power plant such as following items: 1) providing the technical prevention manual of the hydrogen explosions and hydrogen fires occurring in the cooling system of power generator; 2) the selection of explosion-proof equipments in terms of the risk level of operating environment; 3) the establishment of regulations and counter measures, such as the incorporation of gas leakage alarm device, for preventing the accidents from arising; 4) the establishment of safety management system to ensure the normal operation of the power plant.

• 한국연소학회지
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• 제12권3호
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• pp.1-7
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• 2007

A combined hydrogen generator of plasma and catalytic reformer was developed, and was applied to stabilize unstable flame of 200,000 Kcal/hr LPG combustor. The role of the plasma reformer was to generate hydrogen in a short period and to heat-up the catalytic reformer during the start-up time. After the start-up period, the catalytic reformer generates hydrogen through steam reforming with oxygen (SRO) reactions. The maximum capacity of the hydrogen generator was enough 100 lpm to stabilize the flame of the present combustor. In order to reduce NOx and CO emissions simultaneously, 1) FGR (Flue Gas Recirculation) technique has been adopted and 2) the hydrogen was added into the fuel supplied to the combustor. Test results showed that the addition of 25% hydrogen and 30% FGR rate lead to simultaneous decrease of CO and NOx emissions. The technique developed in the present study showed good potential to replace $NH_3$ SCR technique, especially in the small-scale combustor applications.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2007년도 제34회 KOSCO SYMPOSIUM 논문집
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• pp.187-190
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• 2007

A combined hydrogen generator of plasma and catalytic reformers has been developed, and has been applied to stabilize unstable flame of 200,000 Kcal/hr LPG combustor. The role of the plasma reformer is to generate hydrogen in a short period and to heat-up the catalytic reformer during the start-up time. After the start-up period, the catalytic reformer generates hydrogen through steam reforming with oxygen (SRO) reactions. The maximum capacity of the hydrogen generator is 100 lpm that is sufficient to be used to stabilize the flame of the present combustor. In order to reduce NOx and CO emissions simultaneously, 1) FGR (Flue Gas Recirculation) technique has been adopted and 2) the hydrogen has been added into the fuel supplied to the combustor. Test results shows that 25 % addition of hydrogen and 30 % FGR rate lead to simultaneous decrease of CO and NOx emissions. The technique proposed in the present study shows good potential to replace $NH_3$ SCR technique, especially in the case of small-scale combustor applications.