• Korean Chemical Engineering Research
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• 제43권3호
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• pp.331-343
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• 2005

연료전지와 수소를 사용하는 연료전지 자동차의 상용화를 위해서는 수소 공급용 수소 스테이션(hydrogen station)의 개발이 중요한 핵심 기반기술이다. 일반적으로 수소 스테이션은 탈황반응, 개질반응(reforming), 수성가스전환(WGS) 반응 및 수소분리(PSA) 장치로 구성된 수소제조 공정과 압축, 저장 및 분배 장치로 구성된 후처리(post-treatment) 공정으로 구성되어 있다. 본 총설에서는 수소 경제(hydrogen economy) 사회로의 진입을 위해 국내외에서 연구개발 중인 수소 스테이션에 대한 연구 개발 동향과 전망을 고찰하였다. 그리고 향후 풍력 및 태양열 등 재생 가능 에너지(renewable energy)원으로부터 물의 분해에 의한 수소제조 기술이 확립되기 전까지는 화석연료의 개질 반응이 수소를 제조하는 핵심기술이 될 것으로 판단된다. 따라서 화석연료의 탈황반응, 화석연료의 개질 반응에 의한 수소제조, CO 농도 저감을 위한 수성가스 전환반응 및 수소의 분리기술 등 수소 스테이션의 상용화에 필수적인 단위공정개발에 대한 최근의 연구동향을 정리하였다.

• 한국수소및신에너지학회논문집
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• 제26권1호
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• pp.64-70
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• 2015

Organic Rankine cycle (ORC) is an useful cycle for power generation system with low temperature heat sources ($80{\sim}400^{\circ}C$). Since the boiling point of operating fluid is low, the system is used to recover the low temperature heat source of waste heat energy. In this study, a ORC with R134a is applied to recover the waste energy of condenser of coal fired power plant. A system model is developed via Thermolib$^{(R)}$ under Simulink/MATLAB environment. The model is composed of a refrigerant heat exchanger for heat recovery from coal fired condenser, a drum, turbine, heat exchanger for ORC heat rejection, storage tank, water recirculation pump and water drip pump. System analysis parameters were heat recovery capacity, type of refrigerants, and types of turbines. The simulation model is used to analyze the heat recovery capacity of ORC power system. As a result, increasing the overall heat transfer coefficient to become the largest of turbine power is the most economical.

• 한국가스학회지
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• 제27권3호
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• pp.19-26
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• 2023

수소는 화석연료를 대체할 수 있는 COx-free 에너지원으로 사용량은 지속적으로 증가할 것이다. 수소는 단위 질량당 에너지 함량이 높으나, 낮은 저장 밀도와 장기 저장의 어려움으로 저장 및 운송에 한계가 존재한다. 반면, 암모니아는 단위 부피당 저장용량이 크고, 비교적 액화가 용이하여 대용량 수소를 저장 및 운송할 수 있는 수소 운반체로 주목받고 있다. 암모니아 분해를 통한 수소 생산 반응은 흡열반응으로 공정의 효율성 및 경제성을 위해 저온 활성이 우수한 촉매 개발이 요구된다. 본 연구에서는 활성금속 Ni의 고분산 담지를 위해 넓은 비표면적의 제올라이트를 지지체로 사용하였으며, 제올라이트 종류(5A, NaY, ZSM5)에 따른 특성(기공구조, 양이온, Si/Al-비)이 촉매 활성 및 반응 특성에 미치는 영향을 확인하였다. 5A 제올라이트는 표면, 기공, 구조체 내에 Ni 을 고분산 담지를 가능하게 하였으며, 낮은 Si/Al-비로 인한 풍부한 산점은 암모니아 흡착을 증가시켰다. 또한, 지지체에 포함된 Na과 Ca 양이온으로 인한 중간-염기점은 질소 탈착속도를 향상시켰다. 따라서, 15wt%Ni/5A 촉매는 강한 금속-지지체 상호작용과 중간-염기점을 통한 질소 탈착 속도 향상으로 가장 우수한 암모니아 전환율과 높은 수소 생성율 23.5 mmol/g_cat·min (30,000 mL/g_cat·h, 600 ℃)을 보였다.

• 한국수소및신에너지학회논문집
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• 제30권1호
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• pp.43-48
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• 2019

This study investigates the electrochemical characteristics of the hybrid cell that combined the advantageous characteristics of Li secondary battery and supercapacitor, high energy density and high power density, respectively. Electrochemical behaviors of the hybrid cell was characterized by charge/discharge, cycle and impedance tests. The hybrid cell using Li secondary battery and supercapacitor had better discharge capacity and cycle performance than that of using Li secondary battery only. Proper design of such a hybrid cell system is expected to result in substantial benefits to the well being of the Li secondary battery. The hybrid cell involving Li secondary battery for high energy density and supercapacitor for high power density may be the possible solution for future energy storage system.

• 한국수소및신에너지학회논문집
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• 제35권1호
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• pp.40-47
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• 2024

Ammonia is drawing attention as carbon free fuel due to its ease of storage and transportation compared to hydrogen. This study suggests ammonia fueled solid oxide fuel cell (SOFC) system with electrochemical hydrogen compressor (EHC)-based recirculation. Performance of electrochemical hydrogen pump is based on the experimental data under varying hydrogen and nitrogen concentration. As a result, the suggested system shows 62.04% net electrical efficiency. The efficiency is 10.33% point higher compared to simple standalone SOFC system (51.71%), but 0.02% point lower compared to blower-based recirculation system (62.06%). Further improvement in the EHC-based SOFC recirculation system can be achieved with EHC performance improvement.

• 한국수소및신에너지학회논문집
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• 제25권4호
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• pp.393-404
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• 2014

Unmanned aerial vehicles (UAVs) have been applied to not only military missions like surveillance and reconnaissance but also commercial missions like meteorological observation, aerial photograph, communication relay, internet network build and disaster observation. Fuel cells make UAVs eco-friendly by using hydrogen. Proton exchange membrane fuel cells (PEMFCs) show low operation temperature, high efficiency, low noise and high energy density and those characterisitcs are well fitted with UAVs. Thus Fuel cell based UAVs have been actively developed in the world. Recently, fuel cell UAVs have started to develope for high altitude UAVs because target altitude of UAVs is expanded upto stratosphere altitude. Long endurance of UAVs is essential to improve effects of the missions. Improvement of UAV endurance time could be fulfilled by developing a hydrogen fuel storage system with high energy density and reducing the weight of UAVs. In this paper, research trend and analysis of fuel cell UAVs are introduced in terms of their altitude and endurance time and then the prospect of fuel cell UAVs are shown.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2005년도 동계학술발표대회 논문집
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• pp.179-185
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• 2005

Nowadays, study about hydrogen fuel which consist of hydrogen extraction process, reforming, fuel cell equipment, and receptacle are flourish all over the world. Currently, Korea hydrogen station is still underdevelopment. Yet the most important part such as hydrogen compressor has not been develop. Therefore, if the high pressure compressor for hydrogen have been developed by domestic technology. In the future many benefit can be gain instead of importing. Such as many hydrogen station can be built in Korea, and also Korea will be able to provide hydrogen system for worldwide. This study is going to analysis hydrogen compressor in order to store high pressure hydrogen. This is almost approach practical use of tile hydrogen storage method.

• 에너지공학
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• 제25권3호
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• pp.66-72
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• 2016

본 연구에서는 술폰화된 sodium 5,5'-carbonylbis(2-fluorobenzene sulfonate) 단량체를 이용하여 친수성 올리고머를 합성한 뒤 소수성 올리고머와 1:1로 공중합반응을 시켜 sulfonated poly(arylene ether ketone) (SPAEK) 공중합체를 합성하였다. 제조한 공중합체의 구조 분석은 $^1H$-NMR, FT-IR, GPC를 사용하여 실시하였고, GPC에서 공중합체의 평균분자량은 $209,700g\;mol^{-1}$, 다분산지수(PDI)는 1.25이었다. 열적 안정성을 확인하기 위하여 TGA 분석을 실시하였고, $200^{\circ}C$이상에서의 열 안정성을 확인하였다. 고분자 전해질 막의 양이온 전도도는 상대습도 100%, $80^{\circ}C$의 온도에서 약 $9.0mS\;cm^{-1}$이었다. 측정된 결과로부터 본 연구에서 제조한 탄화수소계 전해질 막은 술폰화 정도를 증가시키거나 약간의 구조적 변형을 통해 연료전지용 고분자 전해질 막으로 적용 가능할 것으로 기대된다.

• 한국수소및신에너지학회논문집
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• 제35권2호
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• pp.146-151
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• 2024

The demand for research on materials with excellent cryogenic strength and ductility has been increasing, particularly for applications such as liquid hydrogen (20 K) storage tanks. To effectively utilize liquid hydrogen, a system capable of maintaining and operating at 20 K is essential. Therefore, preliminary research and verification of the cooling system are crucial. In this study, a heat transfer analysis was conducted on a cooling system to meet the cryogenic environment requirements for cryogenic hydrogen chamber, which are conducted at liquid helium temperatures (4 K). The cooling mechanism in a helium cooling system was examined using numerical analysis. The numerical cooling trends were compared with experimentally obtained cooling results. The good agreement between numerical and experimental results suggests that the numerical approach developed in this study is applicable over a wide range of cryogenic systems.

• 한국수소및신에너지학회논문집
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• 제32권5호
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• pp.324-330
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• 2021

In recent years, polymer electrolyte membrane fuel cell (PEMFC) based cogeneration system has received more and more attention from energy researchers because beside electricity, the system also meets the residential thermal demand. However, the low-quality heat exited from PEMFC should be increased temperature before direct use or storage. This study proposes a method to utilize the heat exhausted from a 10 kW PEMFC by coupling a heat pump. Two different configuration using heat pump and a reference layout with heater are analyzed in term of thermal and total efficiency. The system coefficient of performance (COP) increases from 0.87 in layout with heaters to 1.26 and 1.29 in configuration with heat pump and cascade heat pump, respectively. Lastly, based on system performance result, another study in economics point of view is proposed.