2단 분류층 가스화기에서 합성가스 생성을 위한 석탄 슬러리 가스화에 대한 수치 해석적 연구

서동균(Seo, Dong-Kyun),이선기(Lee, Sun-Ki),송순호(Song, Soon-Ho),황정호(Hwang, Jung-Ho) 한국신재생에너지학회 2007 한국신재생에너지학회 학술대회논문집 Vol.2007 No.11

Oxy-gasification or oxygen-blown gasification, enables a clean and efficient use of coal and opens a promising way to co₂ capture. The coal gasification process of a slurry feed type, entrained-flow coal gasifier was numerically predicted in this paper. The purposes of this study are to develop an evaluation technique for design and performance optimization of coal gasifiers using a numerical simulation technique, and to confirm the validity of the model. By dividing the complicated coal gasification process into several simplified stages such as slurry evaporation, coal devolatilization, mixture fraction model and two-phase reactions coupled with turbulent flow and two-phase heat transfer, a comprehensive numerical model was constructed to simulate the coal gasification process. The influence of turbulence on the gas properties was taken into account by the PDF (Probability Density Function) model. A numerical simulation with the coal gasification model is performed on the Conoco-Philips type gasifier for IGCC plant. Gas temperature distribution and product gas composition are also presented. Numerical computations were performed to assess the effect of variation in oxygen to coal ratio and steam to coal ratio on reactive flow field. The concentration of major products, CO and H2 were calculated with varying oxygen to coal ratio (0.2-1.5) and steam to coal ratio(0.3-0.7). To verify the validity of predictions, predicted values of CO and H2 concentrations at the exit of the gasifier were compared with previous work of the same geometry and operating points. Predictions showed that the CO and H2 concentration increased gradually to its maximum value with increasing oxygen-coal and hydrogen-coal ratio and decreased. When the oxygen-coal ratio was between 0.8 and 1.2, and the steam-coal ratio was between 0.4 and 0.5, high values of CO and H2 were obtained. This study also deals with the comparison of CFD (Computational Flow Dynamics) and STATNJAN results which consider the objective gasifier as chemical equilibrium to know the effect of flow on objective gasifier compared to equilibrium. This study makes objective gasifier divided into a few ranges to study the evolution of the gasification locally. By this method, we can find that there are characteristics in the each scope divided.

이산화탄소를 이용한 바이오매스 촤 가스화 반응에 대한 연구

이선기(Sun-Ki Lee),서동균(Dong-Kyun Seo),황정호(Jung-Ho Hwang) 한국연소학회 2008 KOSCOSYMPOSIUM논문집 Vol.- No.-

The gasification reactivities of biomass chars with CO2 were investigated. Carbon conversion was measured using a real time gas analyzer. In a lab scale furnace, each biomass sample was pyrolyzed in nitrogen atmosphere and became biomass char, which was then gasified with CO2 under isothermal conditions. The reactivities of biomass chars was investigated at different temperatures and CO2 concentrations. Shrinking core model were used to interpret the experiment data. The activation energy(E) and frequency factor(A) of the biomass char-CO2 reaction were determined from gas analysis data by using Arrhenius equation. The reactivity of chars increased with the increase of gasification temperature. Using FLUENT6.2, one of CFD tool, gasification reaction was modeled. Using coefficients from experiment data, CFD modeling results well agreed with the experiment data

1단 분류층 가스화기의 가스화 반응에 대한 전산해석

강민웅(Min-Woong Kang),서동균(Dong-Kyun Seo),이선기(Sun-Ki Lee),황정호(Jung-Ho Hwang),임성진(Sung-Jin Yim) 한국연소학회 2008 KOSCOSYMPOSIUM논문집 Vol.- No.-

It is important to develop an evaluation technique for design and performance optimization of coal gasifiers using a numerical simulation model, and to confirm the validity of the model. The coal gasification process of an entrained-flow gasifier for integrated coal gasification combined cycle(IGCC) plant, so called as Shell type gasifier, was numerically predicted with a commercial code, FLUENT. By classifying the complicated process into several simplified stages of slurry evaporation, coal devolatilization, and chemical reactions coupled with turbulent flow and heat transfer, a comprehensive numerical model was constructed to simulate the coal gasification process. In this work, we have used Finite rate/eddy dissipation model to have a modeling of chemical/flow interaction. In this model, concentrations of CO and H₂ were calculated for various oxygen to coal ratios(0.29~0.87) at steam to coal ratio, 0.11, and length to diameter ratio(2~4) at oxygen to coal ratios, 0.72, and steam to coal ratio, 0.11. The results showed the operating point for the maximum gasifier efficiency was the O₂/coal ratio, about 0.5, and L/D ratio that was similar from 2 to 4.

Lab-scale 반응기에서 RPF 열분해 가스의 가스화에 의한 합성 가스의 생성에 대한 연구

배수우(Bae, Su-Woo),서동균(Seo, Dong-Kyun),강필선(Kang, Pil-Sun),송순호(Song, Soon-Ho),류태우(Yu, Tae-U),황정호(Hwang, Jung-Ho) 한국신재생에너지학회 2007 한국신재생에너지학회 학술대회논문집 Vol.2007 No.11

This paper provides RPF (Refuse Plastics Fuel) gasification characteristics for generating synthesis gas in gasfying reactor which was design in lab-scale. This research is carried out as an immediate work for making pyrolysis gas from RPF into energy resource. This study is consisted of experimental and numerical. The numerical study was accomplished from RPF pyrolysis data, and predicted the maximum operating conditions by STANJAN and FLEUNT. Based on results of STANJAN, it is found that the maximum point of O₂/O_{2,stoich}=20{sim}30, which is used as injection point of O₂. Experiment results shows that CO and H₂ were increased but THC was decreased as temperature was increased. It is estimated that the cracking of cracking of THC into CO and H2 is happened at a high temperature. It is observed that as steam was injected, production of CO and H2 were increased, then, H2 is dependent on the amount of injectionsteam.

배드민턴 선수의 경쟁 상태불안이 경기결과에 미치는 영향

김응준(Kim Eung-Joon),서동균(Seo Dong-Kyun),조선령(Cho Sun-Lyoung) 한국체육과학회 2007 한국체육과학회지 Vol.16 No.3

The purpose of this study was to examine the changes of cognitive state anxiety, somatic anxiety, and self-confidence of Badminton players before the game according to the result of the game and cognitive component's level. The subjects involved in this study were all the Badminton players who took part in the National Badminton championship in Autumn (2006. 8.31~9. 6):both males and females (middle and high school). The questionnaire used for the study is CSAL-2 developed by Martens et. al. (1977). Most of earlier studies were analyzed and invested under regulated places such as laboratories or artificial competitive states - neither real competitive states nor real players. However, this study examined how the competitive state anxiety of good athletes as well as athletes affected the results of the real games. The results are summarized as follows : First, the cognitive anxiety of both good athletes and athletes had positive correlation to somatic anxiety regardless of the results of the game. Second, the self-confidence of both good athletes and athletes had positive correlation to athletic performance. Third, the cognitive level of the players on their competitors in real competitive state had positive correlation to the level of cognitive state anxiety and somatic anxiety, while it had negative correlation to the level of self-confidence.

코치의 리더십 행동 유형과 스포츠 탈진의 관계

김응준(Kim Eung-Joon),서동균(Seo Dong-Kyun),조선령(Cho Sun-Lyoung),신성득(Shin Sung-Duk),엄정식(Um Jung-Sik) 한국체육과학회 2008 한국체육과학회지 Vol.17 No.3

The purpose of this study was attempted to identify the effect on sports burnout type with sport leadership behavior type(training-instruction, positive support, democratic, autocratic). 258 athletes(man 141, woman 117) selected by 2007 National Sport Festival in this study. They are consist of track & field players(n=116) and ball game players(n=142). The research tool include the following two questionnaires; leadership behavior 'leadership scale for sports; LSS' of Chelladurai & Saleh (1980); SAMBI(Sport Adaptation of the Maslach Burnout Inventory) Fender (1990)'s scale. Descriptive, Correlate, Common factor Analysis ANOVA, Multiple Regression were used to identify relationship between leadership behavior scale and burnout. Results of this study were as following. First, there is a difference of LSS's training & instruction and democratic type as a function of sex at p<.05 level and there is a difference of LSS's democratic type as a function of school level at p<.05 level. Second, there is a statistical effectiveness of emotional exhaustion and depersonalization as a function of LSS's democratic, positive support and autocrat at p<.05 level

조사논문 : 축산 6차 산업화의 유형별 특성에 관한 연구-축산 6차 산업화 우수경영체를 중심으로-

최현호 ( Hyun Ho Choi ),천동원 ( Dong Won Choen ),이상덕 ( Sang Duck Lee ),서동균 ( Dong Kyun Sun ),송영섭 ( Yong Sup Song ) 한국축산경영학회,농업정책학회(구 한국축산경영학회) 2014 농업경영정책연구 Vol.41 No.3

This research field study on management systems operating in Livestock``s6th industrialization, discovered a case of added value for 30 places.Accordingly, this research searched for countermeasures for advancingLivestock``s 6th industrialization``s effectiveness by analyzing the characteristicsof 6th industrialization farm types and identifying problems within theiroperational management systems. The types are divided into the circulationand amenity types. The dairy industry made up most of Livestock`s 6thindustrialization, and did well indirect trading and providing experience. TheHanwoo industry was managed by butchers and restaurants due to the lackof diversity according to the difficulty of the processing experience, but hadthe highest ability to maintain a workforce. The poultry industry depended onthe consumer Cooperative rather than direct trading and had a difficult timeestablishing its value chain. Based on discovered positive prospects of farmmanagement, if a policy is supported that considers the characteristics ofeach type in the first stage of the 6th industrialization, then there is a highpossibility to increase added value by expanding business areas and creatingBlue Ocean. Also, expansion due to the economic ripple effect throughsettlement of Livestock`s 6th industrialization and agriculture growth can beexpected.