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Characterization of Soot Produced from Thermal Decomposition of Hydrocarbon Fuel (탄화수소연료의 열분해 Soot발생특성 분석에 관한 연구)

  • KIM, HAKDUCK;KIM, CHANGYEAN;SONG, JUHUN
    • Journal of Hydrogen and New Energy
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    • v.27 no.6
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    • pp.747-752
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    • 2016
  • Soot and harmful exhaust gas produced by liquid hydrocarbon fuel caused various environmental problems. In this study, soot characteristics produced by thermal decomposition of acetylene and diesel were analyzed, which are formed at different temperatures. These fuels were observed to produce particulate matters, and collected soot samples were observed by using TEM & SEM. These were found to be significantly different in structure and crystallinity.

Modelling of the Resistance Model for Anode and Cathode for Molten Carbonate Fuel Cells (용융탄산염 연료전지용 공기극과 연료극의 저항 모델링)

  • LEE, CHANG-WHAN;JUNG, JUNG-YUL
    • Journal of Hydrogen and New Energy
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    • v.29 no.3
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    • pp.267-273
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    • 2018
  • From the experiments of various temperature and gas compositions, total resistance which is composed of ohmic resistance, anode resistance, cathode resistance and Nernst loss was calculated wit simple assumption. In this work, the anode and the cathode resistance was modelled with new equation which can account for the correlation between the operating temperature and the gas composition. The proposed model can predict the resistance with maximum error of 2.57% and employed in the simulation of molten carbonate fuel cells.

Characteristics of Thermodynamic Performance of Organic Flash Cycle (OFC) with Double Expansion (이중 팽창을 채용한 유기 플래시 사이클(OFC)의 열역학적 성능 특성)

  • KIM, KYOUNG HOON;HAN, CHUL HO;JUNG, YOUNG GUAN
    • Journal of Hydrogen and New Energy
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    • v.29 no.5
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    • pp.483-489
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    • 2018
  • Recently proposed organic flash cycle (OFC) was shown to potentially improve power generation using low grade heat source. In this paper, a thermodynamic performance is carried out for a modified OFC employed double expansions. Effects of the selection of working fluid and the important system parameters such as the temperatures in flash evaporators on the system performance were extensively investigated. Results showed that the system performances are strongly influenced with the system parameters and selection of the working fluid, and the power generation can be increased compared to the basic OFC.

Performance Analysis of a Combined Cycle of Kalina and Absorption Refrigeration for Recovery of Low-Temperature Heat Source (저온 열원의 활용을 위한 칼리나/흡수냉동 복합사이클의 성능 해석)

  • KIM, KYOUNG HOON;KO, HYUNG JONG;JUNG, YOUNG GUAN
    • Journal of Hydrogen and New Energy
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    • v.29 no.5
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    • pp.490-496
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    • 2018
  • Recently, the power and refrigeration cogeneration based on Kalina cycle has attracted much attention for more efficient utilization of low-grade energy. This study presents a thermodynamic performance analysis of a cogeneration cycle of power and absorption refrigeration based on Kalina cycle. The cycle combines Kalina cycle (KCS-11) and absorption cycles by adding a condenser and an evaporator between turbine and absorber. The effects of ammonia mass fraction and separation pressure were investigated on the system performance of the system. Results showed that the energy utilization of the system could be greatly improved compared to the basic Kalina cycle.

A Experiment of Combustion Behavior of Biomass Fuels (바이오매스 연료의 연소 특성 실험)

  • KIM, HAKDEOK;KIM, YOUNGDAE;SONG, JUHUN
    • Journal of Hydrogen and New Energy
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    • v.29 no.5
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    • pp.503-511
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    • 2018
  • There have been many studies of combustion in the circulating fluidized bed. However, little study is available for combustion of wood pellet together fed with wood chip. The mixed ratio of two fuels is an useful information when thermal power company would receive the Renewable Energy Portfolio Standard (RPS) from government. In this study, the combustion behavior and kinetics of such biomass fuels are evaluated using fluidized bed reactor and thermogravimetric analyzers. The mixing ratio of wood chip relative to wood pellet was varied at different temperatures. The results show that a combustion reactivity changed significantly at the wood chip mixing ratio of 40%, particularly at low temperature condition.

Characteristics of Byproducts during Anaerobic Hydrogen Fermentation Using Protein (단백질을 이용한 혐기성 수소 발효시 부산물 발생 특성 평가)

  • LEE, CHAE-YOUNG;HAN, SUN-KEE
    • Journal of Hydrogen and New Energy
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    • v.29 no.5
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    • pp.427-433
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    • 2018
  • This study was performed to evaluate initial pH and substrate concentration on hydrogen fermentation of protein. The optimum initial pH and substrate concentration of hydrogen fermentation using protein was 8.0 and 1.0 g peptone/L, respectively. The maximum hydrogen yield at initial pH 8.0 and 1.0 g peptone/L was $19.2{\pm}0.8mL\;H_2/g$ peptone. As results of VFAs analysis, percentages of valerate was similar to hydrogen yield. Also, C. stickalandii, which was hydrogen and valerate producing bacteria, was dominated.

Thermal Performance Analysis of Reciprocating Compressors for Refrigerator-freezers (냉장고용 왕복동 압축기의 성능 해석)

  • KIM, MAN-HOE
    • Journal of Hydrogen and New Energy
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    • v.27 no.2
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    • pp.236-243
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    • 2016
  • This paper presents a simple thermo-physical model of reciprocating compressors for household refrigerator-freezers. The compressor model has been developed based on thermodynamic principles and large data sets from the compressor calorimeter tests. The input data are compressor geometry (displacement and clearance volume), compressor speed, suction pressure and temperature, discharge pressure, and ambient temperature. The model can estimate mass flow rate and compressor power consumption within 3.0% accuracy, which is not much larger than measurement errors associated with calorimeter testing under ideal conditions.

Preparation and Characteristics of Pt/GDE Loaded with Pd Promoter for PEMFC (Pd 조촉매가 도입된 PEMFC용 Pt/GDE 제조 및 특성)

  • LEE, HONGKI;LEE, WOOKUM
    • Journal of Hydrogen and New Energy
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    • v.27 no.3
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    • pp.264-269
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    • 2016
  • A simple dry chemical approach was developed in order to load palladium (Pd) as a promoter on Pt/gas diffusion electrode (GDE) for polymer electrolyte membrane fuel cell (PEMFC). Palladium(II) bis (acetylacetonate), $Pd(acac)_2$ was sublimed, penetrated into Pt/GDE and then reduced to Pd nanoparticles simultaneously without any reducing agent and any solvent in a glass reactor of $N_2$ atmosphere at $180^{\circ}C$ for 3, 5 and 15 min. Pd distribution was analyzed by scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS), and I-V curve was estimated by using a unit cell with $5{\times}5cm^2$ active area.

Development of the Social Responsibility Program (Aspect of Energy & Environmenrs) under CO2 Emission Trading Systems (탄소배출권 거래제도에 따른 기업의 에너지·환경 사회공헌 프로그램 도출 방법론)

  • AHN, JOONGWOO
    • Journal of Hydrogen and New Energy
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    • v.26 no.5
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    • pp.453-462
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    • 2015
  • In this study, a methodology is investigated for the development of social responsibility program employed by major domestic companies under social pressure. It is true, however, that its infancy in history and lack of experience makes it difficult to run novel programs for the companies on their own and it naturally leads to copying and/or slight modification of what others do. Utilizing widely accepted SWOT analysis, stakeholders analysis and PDCA Cycle, a methodology for the successful programs with sustainability is proposed by reflecting business nature and strategic direction. Three real cases are analyzed. In addition, relationship and position with social welfare organizations is elucidated.

A Study on Geothermal System Applicability of a Detached House (단독주택의 지열시스템 적용 가능성에 대한 연구)

  • Shin, Cheulsoo;Jang, Taeik
    • Journal of Hydrogen and New Energy
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    • v.23 no.5
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    • pp.551-558
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    • 2012
  • Due to high oil prices and global warming problems, researching an alternative energy source and decreasing the energy usage will be the key in the future. Unlike other alternative energy sources, geothermal energy is less dependent on the surrounding environment. Geothermal energy is the ideal energy source for buildings due to the simple and space saving installation. The system is semi permanent once it is installed and this will help reduce the energy usage in controlling the climate in buildings. Geothermal energy does not emit carbon dioxide and other gases that are harmful to the environment. Therefore geothermal energy will be the key in solving high oil prices and a decrease in fossil fuels by applying the geothermal energy system to homes to counter future energy crisis.