• Transactions of the Korean hydrogen and new energy society
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• v.23 no.3
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• pp.227-235
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• 2012

Finding an alternative fuel and reducing environmental pollution are the main goals for future internal combustion engines. The purpose of this study is to obtain low-emission and high-efficiency by hydrogen enriched LPG fuel in constant volume chamber. An experimental study was carried out to obtain fundamental data for the combustion and emission characteristics of pre-mixed hydrogen and LPG in a constant volume chamber (CVC) with various fractions of hydrogen-LPG blends. To maintain equal heating value of fuel blend, the amount of LPG was decreased as hydrogen was gradually added. Exhaust emissions were measured using a HORIBA exhaust gas analyzer for various fractions of hydrogen-LPG blends. The results showed that the rapid combustion duration was shortened, and the rate of heat release elevated as the hydrogen fraction in the fuel blend was increased. Moreover, the maximum rate of pressure rise also increased. These phenomena were attributed to the burning velocity which increased exponentially with the increased hydrogen fraction in the $H_2$-LPG fuel blend. Exhaust HC and $CO_2$ concentrations decreased, while NOX emission increased with an increase in the hydrogen fraction in the fuel blend. Our results could facilitate the application of hydrogen and LPG as a fuel in the current fossil hydrocarbon-based economy and the strict emission regulations in internal combustion engines.

• Journal of the Korean Society of Propulsion Engineers
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• v.14 no.4
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• pp.46-58
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• 2010

Hydrogen peroxide(HP) and liquid methane have deserved renewed considerations as green propellants in recent years, because main design concerns in the development of the new generation propulsion system for spacecrafts are concentrated on low operation cost and environmental cleanness. Although HP has a long history of application to aerospace propulsion systems due to high density, mono-propellant characteristics and low toxicity, it had been replaced by hydrazine and liquid oxygen due to extreme performance requirement during the cold war. But HP has received a renewed interest due to its increased stability and many researches have been conducted to develop high performance LREs(Liquid Rocket Engines) using HP. Liquid methane has also received a new interest in rocket propulsion system for the future space exploration according to its possibility of ISRU(In-Situ Resource Utilization).

• The Science & Technology
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• v.11 no.10 s.113
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• pp.27-29
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• 1978

세계의 석유자원은 향후 30년의 가채년수 뿐일 것이라는 추정은 이제 상식화된 느낌이다. 그래서 세계 선진국들은 석유를 대신할수 있는 에너지원으로서 석탄의 가스 액화, 수소, 원자력, 태양열광 등의 개발을 추진하고 있다. 아직 우리는 석유의 꿈을 버리지 않고 있으며, 한편으로는 원자력 발전소 건설에 기대하고 있다. 국내에도 태양에너지 연구가 활발히 진행되고 있는 줄 안다. 고리에 원자발전 제1기를 점화한 우리는 계속 2,3,4의 발전소를 계획하고 있다. 따라서 1990년대 우리 나라 소요에너지의 75%를 원자력에 두게 될 것이라는 전망이고 보면 향후 우리의 생활과 원자력 발전은 불가분의 관계를 이끌어가게 될 것으로 본다. 우리는 지금 육상에서 원자력 발전을 이용하는 단계이나 선진제국은 원자력을 선박 추진력에 이용하는 단계에 있다. 미국을 비롯해서 소련, 영국, 서독, 프랑스, 일본 등이 원자력선 개발에 열을 올리고 있어 앞으로 10년 뒤에는 원자력선 시대의 막이 올려질 것으로 전망된다.

• The Magazine for Energy Service Companies
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• s.46
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• pp.64-65
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• 2007

고등기술연구원 플랜트엔지니어링센터에서는 10년이상 축적된 기반기술과 연구 설비를 환경 및 에너지 분야의 다양한 플랜트에 적용하고 있으며, 고부가가치 창출물 목표로 대기업 및 중소기업을 지원하고 있다. 석탄과 중질잔사유 등 다양한 원료의 가스화와 액화기술 개발 및 열분해/가스화 용융기술의 광범위한 적용을 통하여 생활/산업 폐기물을 환경에 적합하게 처리할 수 있는 공정기술 개발을 하고 있다. 또한 플랜트의 설계/건설/시운전까지 종합한 turn-key서비스를 제공하고 있다. 뿐만 아니라 차세대에너지원인 수소제조를 위한 고온 수전해 전극개발 및 지구온난화 가스를 저감하는 촉매와 공정기술계발, 환경에너지 분야에 대한중소기업 기술지원에도 중점을 두고 있다. 고온고압의 석탄가스화 연구로부터 축적된 가스화용융에 대한 기반기술을 하수슬러지 및 생활폐기물 처리에 성공적으로 적용하여,2003년 1뭘과 12월에 환경부 신기술을 각각 지정 받은 바 있다.

• Korean journal of applied entomology
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• v.10 no.2
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• pp.97-101
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• 1971

1. The experiment was conducted to investigate the physiological characteristics on ten isolates of bacterial leaf blight pathogen of rice, Xanthomenas eryzae Dowson. Seven out of tin isolates were isolated from infected leaves of various rice varieties including IR strains in Korea. Isolates S-20 and S-103 were originated from IRRI in Philippines, and isolate H-5809 was allocated by National Institute of Agricultural Science in Japan. 2. All isolates Produced hydrogen sulfide and ammonia 9as from peptone sol. media, and reduced methylen blue, Gelatin liquefaction occurred by all isolates tested, although each isolate showed different degree of liquefaction No coagulation of the casein in milk by the isolates was observed, though some amount of acid production occurred in litmus milk by ail isolates tested. 3. All isolates utilized glucose and galactose, and slight utilization of esculin, mannitol, raffinose, salicin and saccharose was observed. Lactose, starch and dextrin, however, were not utilized at all by all isolates tested in the study.

• The Korean Journal of Petroleum Geology
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• v.14 no.1
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• pp.45-52
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• 2008

The GTL(Gas to Liquids) technology, manufacturing synthesized oil from natural gas, had been developed about 1920 for the military purpose by Fischer and Tropsch, German scientists. And 1960, Sasol company had started commercializing the FT(Fischer-Tropsch) synthesis technology, for the transport fuel in South Africa. Until a recent date, the commercialization of GTL technology had been delayed by low oil price. But concern about depletion of petroleum resources, and development in synthesizing technology lead to spotlight on the GTL businesses. Especially, Qatar, which has rich natural gas fields, aims at utilizing natural gas like conventional oil resources. Therefore, around this nation, GTL plants construction has been promoted. There are mainly 3 processes to make GTL products(Diesel, Naphtha, lube oil, etc) from natural gas. The first is synthesis gas generation unit reforming hydrogen and carbomonoxide from natural gas. The second is FT synthesis unit converting synthesized gas to polymeric chain-hydrocarbon. The third is product upgrading unit making oil products from the FT synthesized oil. There are quite a little sulfur, nitrogen, and aromatic compounds in GTL products. GTL product has environmental premium in discharging less harmful particles than refinery oil products from crude to the human body. In short, the GTL is a clean technology, easier transportation mean, and has higher stability comparing to LNG works.

• Journal of the Korean Institute of Gas
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• v.25 no.4
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• pp.49-56
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• 2021

Liquefied Petroleum Gas is divided into liquefied gases containing propane (C₃H₈) and butane (C₄H₁₀). The quality of LPG varies greatly depending on the composition of the mixture, so it is important to measure the composition accurately. It is difficult to determine the composition of the mixture because liquid and gas coexist at room temperature. Therefore, the uncertainty in determining the concentration of hydrocarbons by component is high, and there are many problems that differ from the actual content standard. Therefore, it is necessary to develop a mixed liquid propane standard gas for the composition and accurate concentration of hydrocarbon substances. Mixed liquid propane standard gas is manufactured into bellows-type constant-pressure cylinders by ISO-6142 (2015). The homogeneity of the four standard gases manufactured was confirmed to be GC-FID. The manufacturer's uncertainty of expansion was 0.01 % to 0.30 % and homogeneity was 0.03 % to 0.25 %. In this mixed liquid propane standard gas, the relative expansion uncertainty of weight method, manufacturing consistency, cylinder adsorption and long-term stability was developed within 0.26 %-1.3 9% (95% of confidence level, k=2).

• Journal of the Korean Institute of Gas
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• v.27 no.3
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• pp.19-26
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• 2023

Hydrogen, a clean energy source free of COx emissions, is poised to replace fossil fuels, with its usage on the rise. Despite its high energy content per unit mass, hydrogen faces limitations in storage and transportation due to its low storage density and challenges in long-term storage. In contrast, ammonia offers a high storage capacity per unit volume and is relatively easy to liquefy, making it an attractive option for storing and transporting large volumes of hydrogen. While NH₃ decomposition is an endothermic reaction, achieving excellent low-temperature catalytic activity is essential for process efficiency and cost-effectiveness. The study examined the effects of different zeolite types (5A, NaY, ZSM5) on NH₃ decomposition activity, considering differences in pore structure, cations, and Si/Al-ratio. Notably, the 5A zeolite facilitated the high dispersion of Ni across the surface, inside pores, and within the structure. Its low Si/Al ratio contributed to abundant acidity, enhancing ammonia adsorption. Additionally, the presence of Na and Ca cations in the support created medium basic sites that improved N₂ desorption rates. As a result, among the prepared catalysts, the 15 wt%Ni/5A catalyst exhibited the highest NH₃ conversion and a high H₂ formation rate of 23.5 mmol/g_cat·min (30,000 mL/g_cat·h, 600 ℃). This performance was attributed to the strong metal-support interaction and the enhancement of N₂ desorption rates through the presence of medium basic sites.

• Transactions of the Korean hydrogen and new energy society
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• v.25 no.3
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• pp.247-254
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• 2014

The synthesis of Fischer-Tropsch oil is the catalytic hydrogenation of CO to give a range of products, which can be used for the production of high-quality diesel fuel, gasoline and linear chemicals. Our cobalt based catalyst was prepared Co/alumina, silica and titania by the incipient wet impregnation of the nitrates of cobalt and promoter with supports. Cobalt catalysts was calcined at $350^{\circ}C$ before being loaded into the FT reactors. After the reduction of catalyst has been carried out under $450^{\circ}C$ for 24hrs, FT reaction of the catalyst has been carried out at GHSV of 4,000/hr under $200^{\circ}C$ and 20atm. From these test results, we have obtained the results as following ; in case of 12wt% Co-supported $Al_2O_3$, $SiO_2$ and $TiO_2$ catalysts, maximum activities of the catalysts were appeared at the promoters of Mn, Mo and Ce respectively. The activity of 12wt% $Co/Al_2O_3$ added a Mn promoter was about 3 times as high as that of 12wt% $Co/Al_2O_3$ catalyst without promoters. When it has been the experiment at the range of reaction temperature of $200{\sim}220^{\circ}C$ and GHSV of 1,546~5,000/hr, the results have shown generally increasing the activities with the increase of reaction temperature and GHSV.

• Transactions of the Korean hydrogen and new energy society
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• v.28 no.4
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• pp.401-406
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• 2017

When Liquified Natural Gas (LNG) is vaporized into NG for industrial and household usage, tremendous cold energy was transferred from LNG to seawater during phase-changing process. This heat exchanger loop is not only a waste of huge cold energy, but will cause thermal pollution to the coastal fishery area also when cold water was re-injected into the sea. In this study, an innovation design has been performed to reclaim the cold energy for -35 to $62^{\circ}C$ refrigerated warehouse. Conventionally, this was done by installing mechanical refrigeration systems, necessitating tremendous electrical power to drive temperature. A closed loop LNG heat exchangers in series was designed to replace the mechanical or vapor-compression refrigeration cycle by process simulator. The process simulation software of PRO II with provision has been used to simulate this process for various conditions, what to effect on cold energy and used energy for re-liquefaction and evaporation process. In addition, through analysis the effect of the change of LNG supply pressure on sensible and latent heat, optimum operational conditions was suggested for LNG cold energy warehouse.