分流式氧化劑進給是德士古氣化爐特有的設計，在中心噴嘴的部分，是採用水煤漿與氧化劑於同一軸向噴注，並於氣化爐頂設置氧化劑次通道，使得氧化劑分支出二次氣流。此分流進給的方式，將影響火焰產生的位置，對於氣化效能以及煤炭轉換率上亦有所影響。本研究採用商用計算軟體ANSYS-FLUENT，針對德士古的挾帶床式氣化爐，建立一氣化燃燒之數值分析模式。而本研究針對不同次通道位置、不同氧碳比，以及不同次通道流速等操作參數進行探討，比較其對於爐內成份分佈以及氣化效能的影響。在不同次通道位置的測試中，顯示出次通道位置確實會影響燃燒火焰的發生位置，且隨著次通道位置遠離中心軸，將導致火焰面略為延長，造成下游平均溫度提高。在不同氧碳比的測試中，採用高氧碳比的預測結果有較高的煤炭轉化率，然而提高的氧碳比也使得更多氣化產物因燃燒反應而消耗，造成冷氣體效率降低。在不同次通道流速的測試中，次通道流速對於燃燒反應區的分佈以及燃料轉化效率有顯著的影響，當次通道流速提升，高溫反應區有拉深的現象，且碳轉換率以及冷氣體效率也有逐漸下降的趨勢。在研究中亦發現水氣轉換反應對於平衡出口成份的影響十分顯著，且水氣轉換反應的成份平衡對於爐內溫度非常敏感。

The characteristic design of a Texaco gasifier, with a coaxial coal-slurry oxygen-jet nozzle and an outer annular oxygen-jet, has a significant influence on the gasification process. For the fuel-oxidant coaxial jet nozzle, the central oxygen-jet flow impinges on the coal-slurry stream and assists in the atomization of the coal slurry. The outer oxygen-jet, which splits the oxygen intake stream into two, makes an influence of the flame position and causes an effect of the gasification efficiency and coal conversion rate. In the study, numerical simulations of the coal slurry gasification process inside an entrained-flow gasifier with separate oxygen feeding streams are investigated using the commercial computational fluid dynamic software, ANSYS/ FLUENT. Three parameters, namely, positions of the outer annulus feeding tunnel, oxygen/carbon ratio, and oxygen feeding velocity of the outer annulus streams, have been examined to determine the effects of operating conditions on the gasification process. The numerical results show that the flame distribution is affected by the positions of the outer tunnel. As the outer tunnel is moved away from the central axis, the flame surface is extended and leads to a higher temperature in the downstream of the gasifier. In the investigations of the oxygen/carbon ratio, the lower the oxygen/carbon ratio is, the lower outlet temperature and the poorer the coal conversion rate. The distribution of the combustion region and the coal conversion rate is strongly affected by the feeding velocity of the outer annulus stream. The coal conversion rate and the cold gas efficiency are in a descending trend when the oxidant feeding is operated in high velocity. The compositions of the product gases are affected by the WGS. Moreover, the reaction rate of the WGS reaction is sensitive to the temperature of the gasification chamber.

【1】 經濟部能源局, "能源統計手冊," 2013.
【2】 黃正忠, "台灣淨煤技術發展現況與展望," 中技社96年度環境與能源國際研討會,台北, pp. 2-12, 2007.
【3】 鐘文清, "IGCC 發電方式簡介," 技術與訓練, vol. 23, pp. 127-133, 1998.
【4】 華誠系統科技股份有限公司, "潔淨能源 - 煤炭氣化技術介紹," 擷取日期：2014年7月1日, (取自http://www.hpec.com.tw/),燃燒 V.S. 氣化.
【5】 R. I. Singh, A. Brink, and M. Huppa, “CFD Modeling to Study Fluidized Bed Combustion and Gasification,” Applied Thermal Engineering, vol. 52, pp. 585-614, 2013.
【6】 呂錫民, "高效率 低汙染 淨煤技術前景可期," 科學發展, vol. 435, pp. 62-66, 2009.
【7】 姚強、陳超, "潔淨煤技術,"化學工業出版社, 北京, ISBN: 7502560300, pp. 179-289, 2006.
【8】 蔡慶達, "煤炭在固定床中氣化特性之探討," 碩士論文, 輔英科技大學環境工程衛生系所, 2004.
【9】 羅國肇, "流體化床燃燒爐-由糖炒栗子談起," 科學發展, vol 450, pp.6-11, 2010.
【10】 周志成, "石油焦氣化技術研究," 碩士論文, 國立成功大學航空太空工程研究所, 2002.
【11】 財團法人工業技術研究院, "淨煤技術及二氧化碳捕獲封存技術發展計畫(第一年度)," 經濟部能源科技研究發展計畫九十九年度執行報告, vol. 1, pp.14-17, 2011.
【12】 淨煤、捕碳與儲碳主軸專案計畫, "燃燒前捕捉技術, " 擷取日期：2014年7月16日, (取自：http://www.ccsu.org.tw/), 2013.
【13】 林立夫, "淨煤主軸計畫之現況與展望-台灣SOFC技術產業化之挑戰與機會," 擷取日期：2014年7月12日, (取自：http://www.ccsu.org.tw/content/news/news_content.aspx?sid=35), 2012.
【14】 D. B. Anthony and J. B. Howard, "Coal Devolatilization and Hydrogasification," American Institute of Chemical Engineers, vol. 22, pp. 625-656, 1976.
【15】 A. Pradeep K, "A Single Particle Model for the Evolution and Combustion of Coal Volatiles," Fuel, vol. 65, pp. 803-810, 1986.
【16】 L. D. Smoot and B. W. Brown, "Controlling Mechanisms in Gasification of Pulverized Coal," Fuel, vol. 66, pp. 1249-1256, 1987.
【17】 I. W. Smith, "The Combustion Rates of Coal Chars: A Review," The Combustion Institute, vol 19, pp. 1045-1065, 1982.
【18】 H. M. Tolvanen, L. I. Kokko, and R. Raiko, "The Factors Controlling Combustion and Gasification Kinetics of Solid Fuels," The Swedish and Finnish National Committees of the International Flame Research Foundation, Tampere, pp. 1-14, 2011.
【19】 E. D. Ducarne, J. C. Dolignier, and E. Marty, "Modelling of Gaseous Pollutants Emissions in Circulating Fluidized Bed Combustion of Municipal Refuse," Fuel, vol 77, pp. 1399-1410, 1998.
【20】 T. Wang and A. Silaen, "Effects of Turbulence and Devolatilization Models on Gasification Simulation," International Pittsburgh Coal Conference, Pittsburgh, 2008.
【21】 M. Kumar and A. F. Ghoniem, "Multiphysics Simulations of Entrained Flow Gasification. Part II: Constructing and Validating the Overall Model, " Energy Fuels, vol 26, pp.464-479, 2012.
【22】 M. Rehm, P. Seifert, and B. Meyer, "Theoretical and Numerical Investigation on the EDC-Model for Turbulence–Chemistry Interaction at Gasification Conditions," Computers and Chemical Engineering, vol. 33, pp. 402-407, 2009.
【23】 T. Wang and A. Silaen, "Comparison of Instantaneous, Equilibrium, and Finite-Rate Gasification Models in an Entrained-Flow Coal Gasifier," International Pittsburgh Coal Conference, Pittsburgh, 2009.
【24】 H. Watanabe and M. Otaka, "Numerical Simulation of Coal Gasification in Entrained Flow Coal Gasifier," Fuel, vol 85, pp. 1935-1943, 2006.
【25】 T. F. Wall, G.-s. Liu, H.-w. Wu, D. G. Roberts, K. E. Benfell, S. Gupta, J. A. Lucas, and D. J. Harris, "The Effects of Pressure on Coal Reactions During Pulverised Coal Combustion and Gasification," Progress in Energy and Combustion Science, vol. 28, pp. 405-433, 2002.
【26】 A. Pradeep K, "A Single Particle Model for the Evolution and Combustion of Coal Volatiles," Fuel, vol. 65, pp. 803-810, 1986.
【27】 A. Ajilkumar, T. Sundararajan, and U. S. P. Shet, "Numerical Modeling of a Steam-Assisted Tubular Coal Gasifier," International Journal of Thermal Sciences, vol. 48, pp. 308-321, 2009.
【28】 Q. Ni and A. Williams, "A Simulation Study on the Performance of an Entrained-Flow Coal Gasifier," Fuel, vol. 74, pp. 102-110, 1995.
【29】 C. Chen, M. Horio, and T. Kojima, "Numerical Simulation of Entrained Flow Coal Gasifiers. Part II: Effects of Operating Conditions on Gasifier Performance," Chemical Engineering Science, vol. 55, pp. 3875-3883, 2000.
【30】 Y.-T. Luan, Y.-P. Chyou, and T. Wang, "Numerical Analysis of Gasification Performance via Finite-Rate Model in a Cross-Type Two-Stage Gasifer," International Pittsburgh Coal Conference, Pittsburgh, 2011.
【31】 K. Liu, C. Song, and V. Subramani, "Hydrogen and Syngas Production and Purification Technologies," American Institute of Chemical Engineers, John Wiley & Sons, Inc., ISBN: 9780471719755, New York, 2010.
【32】 N. Crnomarkovic, B. Repic, R. Mladenovic, O. Neskovic, and M. Veljkovic, "Experimental Investigation of Role of Steam in Entrained Flow Coal Gsasification," Fuel, vol. 86, pp. 194-202, 2007.
【33】 T. Wang, A. Silaen, H. W. Hsu, and M. C. Lo, "Part-Load Simulations and Experiments of A Small Coal Gasifier," International Pittsburgh Coal Conference, Pittsburgh, 2006.
【34】 Q. W. Wang, P. Liu, S. Xu, and B. Wang, "A Parametric Study to Design An Effective Spray Cooling Deployment in An Entrained-Flow Coal Gasifier," International Pittsburgh Coal Conference, Pittsburgh, 2008.
【35】 C. Chen, M. Horio, and T. Kojima, "Use of Numerical Modeling in the Design and Scale-up of Entrained Flow Coal Gasifiers," Fuel, vol. 80, pp. 1513-1523, 2001.
【36】 T. Wang, A. Silaen, H.-W. Hsu and C.-H. Shen, "Effect of Slag Tap Size on Gasification Performance and Heat Losses in A Quench-Type Coal Gasifier," International Pittsburgh Coal Conference, Johannesburg, 2007.
【37】 T. Wang and X. Lu, "Investigastion of Two-Stage Oxygen Feeding in a Downdraft Entrained-Flow Coal Gasifier," International Pittsburgh Coal Conference, Pittsburg, 2007.
【38】 J.-S. Zhang, Y.-X. Wu and Q. Liu, "Effect of Second Airflow on Three-Dimensional Velocity Distribution in Staged Coal Gasifier," Journal of Combustion Science and Technology, vol. 13, pp.131-135, 2007.
【39】 T. Wang, A. Silaen, H.-W. Hsu, and C.-H Shen, "Investigation of Heat Transfer and Gasification of Two Different Fuel Injectors in An Eentrained Flow Gasifier," International Pittsburgh Coal Conference, Pittsburgh, 2008.
【40】 Y.-X. Wu ,J.-S. Zhang and G.-X. Yue, "Numerical Simulation of the Gas Flow Field From a Triple Channel Coal-Water Slurry Gasifier Nozzle," Journal of Tsinghua University(Science and Technology), vol. 46, pp. 691-695, 2006.
【41】 郭家豪, "粉媒氣化之三維數值模擬分析," 碩士論文, 國立成功大學航空太空工程研究所, 2005.
【42】 洪孟逸, "挾帶床煤炭氣化之模擬," 碩士論文, 國立中山大學機械工程研究所, 1993.
【43】 C.-J. Chen, C.-I. Hung, and W.-H. Chen, "Numerical Investigation on Performance of Coal Gasification Under Various Injection Patterns in An Entrained Flow Gasifier," Applied Energy, vol. 100, pp. 218-228, 2012.
【44】 陳銘宏、陳柏壯、邱耀平、江滄柳、吳泰斌, " Analyses of an Entrained-Bed Coal Gasifier Using a CFD Model Coupled with Chemical Reaction Kinetics," International Pittsburgh Coal Conference, Pittsburgh, 2011.
【45】 劉其瀚, "壓力式粉煤挾帶床氣化爐之燃燒模擬比較及操作條件分析," 碩士論文, 國立成功大學航空太空工程研究所, 2012.
【46】 F. G. Schmitt, "About Boussinesq's Turbulent Viscosity Hypothesis: Historical Remarks and a Direct Evaluation of Its Validity," Comptes Rendus Mécanique, vol. 335, pp. 617-627, 2007.
【47】 B. E. Launder and D. B. Spalding, Lectures in Mathematical Models of Turbulence, Academic Press Inc, ISBN: 9780124380509, London and New York, 1972.
【48】 S. A. Morsi and A. J. Alexander, "An Investigation of Particle Trajectories in Two-Phase Flow Systems," J. Fluid Mechanism., vol. 55, pp. 193-208, 1972.
【49】 W. E. Ranz and W. R. Marshall, "Evaporation from Drops. part 1," Chemical Engineering Progress (CEP) magazine, vol. 18, pp. 141-146, 1952.
【50】 P. Cheng, "Two-Dimensional Radiating Gas Flow by a Moment Method," American Institute of Aeronautics and Astronautics, vol. 2, pp. 1662-1664, 1964.
【51】 W. E. Ranz and W. R. Marshall, Jr. "Evaporation from Drops. part II," Chemical Engineering Progress (CEP) magazine, vol. 48, pp. 173-180, 1952.
【52】 H. Kobayashi, J. B. Howard, and A. F. Sarofim, "Coal Devolatilization at High Temperatures," Symposium (International) on Combustion, vol. 16, pp. 411-425, 1977.
【53】 S. W. Du and W. T. Cheng, "Numerical Prediction and Practical Improvement of Pulverized Coal Combustion in Blast Furnace," International Communications in Heat and Mass Transfer, vol. 33, pp. 327-334, 2006.
【54】 S. W. Du and W. T. Cheng, International Communications in Heat and Mass Transfer, vol. 48, pp. 2069-2076, 2007.
【55】 I. W. Smith, "The Combustion Rates of Coal Chars: A Review, in Proceedings of the 19th International Symposium on Combustion," The Combustion Institute, pp. 1045-1065, 1982.
【56】 C. K. Westbrook and F. L. Dryer, "Simplified Reaction Mechanisms for the Oxidation of Hydrocarbon Fuels in Flames," Combustion Science and Technology, vol. 27, pp. 31-43, 1981.
【57】 N. M. Marinov, C. K. Westbrook, and W. J. Pik, "Detailed and Global Chemical Kinetics Model for Hydrogen," Transport Phenomena in Combustion, San Francisco, vol. 1, pp. 118-129 ,1996.
【58】 J. Ma and S. E. Zitney, "Computational Fluid Dynamic Modeling of Entrained-Flow Gasifiers with Improved Physical and Chemical Submodels," Energy & Fuel, vol. 26, pp. 7195-7219, 2012.
【59】 A DOE Assesment, "Tampa Electrical Integrated Gasification Combined-Cycle Project," U.S. Department of Energy, 2004.
【60】 H. Yoshida and F. Kiyono, "Two-Stage Equilibrium Model for a Coal Gasifier to Predict the Accurate Carbon Conversion in Hydrogen Production," Fuel, vol. 87, pp. 2186-2193, 2008.
【61】 Y. C. Choi and X. Y. Li, "Numerical Study on the Coal Gasification Characteristics in an Entrained Flow Coal Gasifier," Fuel, vol. 80, pp. 2193-2201, 2001.
【62】 S. V. Patankar, "Numerical Heat Transfer and Fluid Flow," Hemisphere Publishing Corporation, Washington-New York-London. McGraw Hill Book Company, ISBN: 0891165223, New York, pp. 113-130,1980.
【63】 B. Smith, M. Loganathan and M. S. Shantha, "A Review of the Water Gas Shift Reaction Kinetics," International Journal of Chemical Reactor Engineering, vol. 8, Review R4, 2010.
【64】 Hydrogen Analysis Resource Center, 擷取日期：2014年7月12日, (取自：http://hydrogen.pnl.gov/cocoon/morf/hydrogen/site_specific/fuel_heating_calculator)