• Transactions of the Korean hydrogen and new energy society
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• v.35 no.4
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• pp.460-467
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• 2024

As the hydrogen economy receives attention, much research has been conducted on water electrolysis that can produce green hydrogen. After investigating the various risk factors that exist in the alkaline water electrolysis process through hazard and operability study and job safety analysis, which are risk assessments, measures to ensure safety were prepared and made into a manual. Possible risks that could occur during various emergency stop situations and operations were identified, and leakage of potassium hydroxide (KOH) and hydrogen used as electrolyte appeared to be the main risk. If you utilize a risk assessment for the relevant equipment when writing a manual, you will be able to prepare work procedures that substantially reduce risk factors.

• The Microorganisms and Industry
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• v.14 no.3
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• pp.41-46
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• 1988

극한환경을 구성하는 중요한 환경인자는 온도, 수소이온농도, 염도, 압력, 물, 영양물질 등이 있는데 본 총설에서는 그동안 비교적 많이 다루어지지 않았던 알칼리성환경, 건조환경, 저영양환경, 심해환경과 같은 극한환경과 아울러 특수환경인 해양환경, 지하환경 등으로 나누어 설명했다. 고염환경과 고영양환경, 혐기성환경은 다른 저자에 의해 자세히 다루어지고 고온환경, 산성환경, 극지환경 등은 지면상 이유로 제외했다.

• Membrane Journal
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• v.6 no.2
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• pp.59-71
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• 1996

기체 막분리공정 기술이 점점 개발되어질수록 막분리의 성능을 이해하려는 필요성이 각 공정에서 증진될 것이며 기체 막분리 성능의 예측능 기술 발전을 위해 계속 시도되어질 것이다. 이러한 추세에 힘입어 현재 석유화학공정 배가스 중 수소를 정제하기 위한 기술 개발을 시도하고 있으며 특히 저농도의 수소를 고농도로 농축시키기 위해 막분리 공정을 적극 검토하고 있다. 본 논문에서 밝혀 본 막분리 공정의 성능 예측과 분석은 향후 공정을 설계하고 제작하는 데 크게 이바지할 뿐만 아니라 석유화학 제반 공정뿐만 아니라 관련 화학공업장치 산업에서 기체 분리를 통한 자원회수와 에너지 절약 측면에서 계속 발전해 나갈 것은 믿어 의심치 않을 것이다.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.06a
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• pp.446-446
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• 2009

표면 패시베이션 기술로 이용되는 수소화된 실리콘 질화막은 제조원가의 절감을 위한 실리콘 기판재료의 두께 감소에 따른 특성상의 문제점을 해결하기 위해 중요한 영향을 미치는 요소이다. 실리콘 질화막은 강한 기계적 강도, 우수한 유전적 특성, 수문에 의한 부식과 유동적 이온에 대한 우수한 저항력 때문에, 반도체 소자 산업에서 널리 사용되고 있다. 수소화된 실리콘 질화막은 반사방지 특성과 함께 표면 패시베이션의 질을 향상시킬 수 있다. 굴절률 1.9 ~ 2.3 범위에서 쉽게 변화 가능한 수소화된 실리콘 질화막은 굴절률 1.4 ~ 1.5 사이의 열적 산화막 보다 효과적인 반사방지막이다. 수소화된 실리콘 질화막을 사용한 태양전지에서는 효율을 높이기 위해서 기판 표면에서의 케리어 재결합이 억제되어져야한다. 또한, 수소화된 실리콘 질화막은 최적화된 두께와 굴절률을 가져야한다. 본 연구에서는 고효율 태양전지에 적용하기 위해 반송자 수명이 향상된 수소화된 실리콘 질화막을 플라즈마 화학 기상 증착법을 이용하여 증착하였다. 박막은 $250^{\circ}C\;{\sim}\;450^{\circ}C$에서 증착되었으며 증착된 박막은 1.94 to 2.05 굴절률 값을 가지고 있다. 반송자 수명을 증가시키기 위해 $650^{\circ}C\;{\sim}\;950^{\circ}C$에서 어닐링 하였고 반송자 수명을 측정하여 패시베이션 특성을 분석하였다. 수소화된 실리콘 질화막은 $850^{\circ}C$의 어닐링 온도와 굴절률 2.0 조건에서 가장 좋은 반송자 수명을 나타냈다.

• KSBB Journal
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• v.20 no.5 s.94
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• pp.350-354
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• 2005

In order to maximize hydrogen production by Enterobacter cloacae YJ-1, anaerobic hydrogen producing bacteria, the medium composition was optimized. Glucose was better than other carbon sources in hydrogen production and its production was 975.4 mL/L at $2\%$ (w/v) for 48 h. Organic nitrogen sources were more effective than inorganic nitrogen sources and also yeast extract among organic nitrogens was the most effective in hydrogen production. Among metal ions, $Na_2MoO_4$ was most effective, and its production was 1753.3mL/L at $0.04\%$ (w/v). Addition of amino acid was very effective with compare to another components of medium, and cystein was most effective among them. Under the optimum medium obtained in batch culture, semi-batch culture in order to produce continuous hydrogen was run. The highest hydrogen production was earned at $3\%$(w/v) of glucose and the amount was 2215.4 mL/L.

• Journal of the Korean Institute of Gas
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• v.26 no.1
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• pp.7-19
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• 2022

Hydrogen purification is generally performed through chemical and physical methods. Among various types of purification method PSA(Pressure Swing Adsorption) is widely used with its purification capacity and economic efficiency. In Korea, most of the hydrogen used in automobiles and power generation fuel cells is purified using PSA. Hydrogen produced in petrochemical complexes has difficulties in transportation. The government is planning to install hydrogen extractors that produce hydrogen directly from consumers in connection with the city gas supply chain, and companies are also installing related research and demonstration facilities one after another. Europe and others have recently established safety standards related to PSA and are making efforts for systematic safety management at the construction and operation stage, but domestic safety standards related to PSA are still insufficient. This study aims to identify problems of existing facilities through surveys and risk assessment by companies operating existing PSA, and to prepare domestic technical standards including them in overseas technical standards to promote the safety of new and existing PSA systems.

• Journal of the Korean Institute of Gas
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• v.26 no.3
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• pp.21-26
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• 2022

Zinc is emerging as a environment-friendly plating material to replace cadmium, which is harmful to the human body, to prevent hydrogen gas penetration or release from metal materials. Electroplating of Zn and Zn alloys, which is usually performed in an aqueous acidic atmosphere, has disadvantages such as low coulombic efficiency, corrosion, and hydrogen release, resulting in industrial use difficult. In this study, a deep-eutectic solvent was synthesized using choline chloride and ethylene glycol. Using this as a solvent, an electrolyte for Zn plating was prepared, and then zinc was plated on the STS 304 substrate. The surface microstructure and roughness were observed using SEM and AFM. The crystal structure of the electro-plated film was analyzed using XRD. Finally, the preventing effects of hydrogen release through Zn-based deep-eutectic plating on the STS 304 substrate were compared with the uncoated substrate.

• Journal of the Korean Institute of Gas
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• v.26 no.6
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• pp.52-58
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• 2022

According to the government's roadmap for revitalizing the hydrogen economy, various industries carry out projects using liquefied hydrogen as an energy source. However, safety standards necessary for operational demonstration projects are not prepared in Korea, thus, it is necessary to prepare safety standards as soon as possible. Therefore, in order to secure the safety of liquefied hydrogen instrumentation and handling facilities, it is necessary to prepare safety standards that comprehensively consider the risk of liquefied hydrogen. This study aims to prioritize safety standard items using ETA, FMEA, and AHP, which are risk assessment techniques, to present the feasibility of selecting safety standard items.

• Journal of Korean Tunnelling and Underground Space Association
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• v.23 no.1
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• pp.47-60
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• 2021

Hydrogen is a next-generation energy source, and according to the roadmap for activating the hydrogen economy, it is expected that industries to stably produce, store, and transport of hydrogen as well as the supply of hydrogen fuel cell vehicles will be made rapidly. Accordingly, safety measures for accidents of hydrogen vehicles in confined spaces such as tunnels are required. In this study, as part of a study to ensure the safety of hydrogen fuel cell vehicles in road tunnels, a basic investigation and research on the risk of fire and explosion due to gas leakage and hydrogen tank rupture among various hazards caused by hydrogen fuel cell vehicle accidents in tunnels was conducted. The following results were obtained. In the event of hydrogen fuel cell vehicle accidents, the gas release rate depends on the orifice diameter of TPRD, and when the gas is ignited, the maximum heat release rate reaches 3.22~51.36 MW (orifice diameter: 1~4 mm) depending on the orifice diameter but the duration times are short. Therefore, it was analyzed that there was little increase in risk due to fire. As the overpressure of the gas explosion was calculated by the equivalent TNT method, in the case of yield of VCE of 0.2 is applied, the safety threshold distance is analyzed to be about 35 m, and number of the equivalent fatalities are conservatively predicted to reach tens of people.

• Journal of Internet Computing and Services
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• v.24 no.6
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• pp.171-180
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• 2023

Hydrogen energy technology is gaining importance in the era of the Fourth Industrial Revolution, offering military advantages when applied to military vehicles due to its characteristics such as reduced greenhouse gas emissions, noise, and low vibration. Korea's military has initiated the Army Tiger 4.0 plan, focusing on hydrogen application, downsizing, and AI-based smart features. The Ministry of National Defense plans to collaborate with the Ministry of Environment to expand hydrogen charging stations nationwide, anticipating increased deployment of military hydrogen vehicles. However, considering the Jet Fire and VCE(Vapor Cloud Explosion) nature of hydrogen, ensuring safety during installation is crucial. Current military guidelines specify a minimum safety distance of 2m from adjacent buildings for charging stations. Scientific methods have been employed to quantitatively assess the accident damage range of hydrogen, proposing a minimum safety distance beyond the affected area.