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Research Papers: Fuel Combustion

A Kinetic Assessment of Entrained Flow Gasification Modeling

[+] Author and Article Information
A. Rakhshi

Department of Mechanical Engineering and
Energy Processes,
Southern Illinois University,
Carbondale, IL 62901
e-mail: aalia.rakhshi@siu.edu

T. Wiltowski

Advanced Coal and Energy Research Center,
Department of Mechanical Engineering and
Energy Processes,
Southern Illinois University,
Carbondale, IL 62901
e-mail: tomek@siu.edu

1Corresponding author.

Contributed by the Advanced Energy Systems Division of ASME for publication in the JOURNAL OF ENERGY RESOURCES TECHNOLOGY. Manuscript received February 5, 2018; final manuscript received April 9, 2018; published online May 29, 2018. Assoc. Editor: Reza Sheikhi.

J. Energy Resour. Technol 140(9), 092204 (May 29, 2018) (9 pages) Paper No: JERT-18-1104; doi: 10.1115/1.4040061 History: Received February 05, 2018; Revised April 09, 2018

A kinetics assessment of the quasi-global homogeneous and heterogeneous reaction mechanisms is carried out for entrained flow coal gasification modeling. Accurate closure of the chemical source term in gasification modeling necessitates a detailed study of turbulence-chemistry interaction. Toward this end, a time-scale analysis of the homogeneous reactions is discussed using eigenvalue analysis of the reaction rate Jacobian matrix. A singular value decomposition (SVD) of the stoichiometric reaction matrix is performed to assess the behavior of the homogeneous reactions in a reduced species vector space. The significant factors affecting the heterogeneous char reactions are assessed, and the relative importance of bulk diffusion and inherent char kinetics is analyzed in a gasifier. The overall study is carried out using numerical and experimental results of an actual pilot scale gasifier.

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References

Li, T. , Gel, A. , Pannala, S. , Shahnam, M. , and Syamlal, M. , 2014, “ CFD Simulations of Circulating Fluidized Bed Risers—Part I: Grid Study,” Powder Technol., 254, pp. 170–180. [CrossRef]
Kaya, E. , and Köksal, M. , 2016, “ Investigation of the Predicting Ability of Single-Phase Chemical Equilibrium Modeling Applied to Circulating Fluidized Bed Coal Gasification,” ASME J. Energy Resour. Technol., 138(3), p. 032203. [CrossRef]
Zhu, Y. , Somasundaram, S. , and Kemp, J. W. , 2010, “ Energy and Exergy Analysis of Gasifier-Based Coal-to-Fuel Systems,” ASME J. Energy Resour. Technol., 132(2), p. 021008. [CrossRef]
Ma, J. , and Zitney, S. E. , 2012, “ Computational Fluid Dynamic Modeling of Entrained-Flow Gasifiers With Improved Physical and Chemical Submodels,” Energy Fuels, 26(12), pp. 7195–7219. [CrossRef]
Xu, J. , and Qiao, L. , 2012, “ Mathematical Modeling of Coal Gasification Processes in a Well-Stirred Reactor: Effects of Devolatilization and Moisture Content,” Energy Fuels, 26(9), pp. 5759–5768. [CrossRef]
Kumar, M. , and Ghoniem, A. F. , 2012, “ Multiphysics Simulations of Entrained Flow Gasification—Part II: Constructing and Validating the Overall Model,” Energy Fuels, 26(1), pp. 464–479. [CrossRef]
Halama, S. , and Spliethoff, H. , 2016, “ Reaction Kinetics of Pressurized Entrained Flow Coal Gasification: Computational Fluid Dynamics Simulation of a 5 MW Siemens Test Gasifier,” ASME J. Energy Resour. Technol., 138(4), p. 042204. [CrossRef]
Shi, S. , Zitney, S. E. , Shahnam, M. , Syamlal, M. , and Rogers, W. A. , 2006, “ Modelling Coal Gasification With CFD and Discrete Phase Method,” J. Energy Inst., 79(4), pp. 217–221. [CrossRef]
Luo, C. , Watanabe, T. , Nakamura, M. , Uemiya, S. , and Kojima, T. , 2000, “ Gasification Kinetics of Coal Chars Carbonized Under Rapid and Slow Heating Conditions at Elevated Temperatures,” ASME J. Energy Resour. Technol., 123(1), pp. 21–26. [CrossRef]
Magnussen, B. , and Hjertager, B. , 1977, “ On Mathematical Modeling of Turbulent Combustion With Special Emphasis on Soot Formation and Combustion,” Symp. (Int.) Combust., 16(1), pp. 719–729. [CrossRef]
Fox, R. O. , 2003, Computational Models for Turbulent Reacting Flows, Cambridge University Press, Cambridge, UK.
Dasgupta, B. , 2006, Applied Mathematical Methods, Pearson Education, Noida, India.
Chen, C. , Horio, M. , and Kojima, T. , 2000, “ Numerical Simulation of Entrained Flow Coal Gasifiers—Part I: Modeling of Coal Gasification in an Entrained Flow Gasifier,” Chem. Eng. Sci., 55(18), pp. 3861–3874. [CrossRef]
Rakhshi, A. , and Wiltowski, T. , 2017, “ A Framework for Devolatilization Breakdown in Entrained Flow Gasification Modeling,” Fuel, 187, pp. 173 –179. [CrossRef]
Pope, S. B. , 2000, Turbulent Flows, Cambridge University Press, Cambridge, UK.
Sazhin, S. S. , 2006, “ Advanced Models of Fuel Droplet Heating and Evaporation,” Prog. Energy Combust. Sci., 32(2), pp. 162–214. [CrossRef]
Kobayashi, H. , Howard, J. B. , and Sarofim, A. F. , 1977, “ Coal Devolatilization at High Temperatures,” Symp. (Int.) Combustion, 16(1), pp. 411–425.
Smith, I. W. , 1982, “ The Combustion Rates of Coal Chars,” Symp. (Int.) Combustion, 19(1), pp. 1045–1065.
Schiller, L. , and Naumann, A. , 1935, “ A Drag Coefficient Correlation,” Z. Ver. Deutsch. Ing., 77, pp. 318–320.
Ranz, W. E. , and Marshall, W. R. , 1952, “ Evaporation From Drops,” Chem. Eng. Prog., 48(3), pp. 141–146.
Powers, J. M. , 2016, Combustion Thermodynamics and Dynamics, Cambridge University Press, Cambridge, UK.
Demirdzic, I. , Lilek, Z. , and Peric, M. , 1993, “ A Collocated Finite Volume Method for Predicting Flows at All Speeds,” Int. J. Numer. Meth. Fluids, 16(12), pp. 1029–1050. [CrossRef]
Date, A. W. , 2011, Analytic Combustion: With Thermodynamics, Chemical Kinetics and Mass Transfer, Cambridge University Press, Cambridge, NY.
Westbrook, C. K. , and Dryer, F. L. , 1981, “ Simplified Reaction Mechanisms for Oxidation of Hydrocarbon Fuels in Flames,” Combust. Sci. Technol., 27(1–2), pp. 31–43. [CrossRef]
Bustamante, F. , Enick, R. M. , Killmeyer, R. P. , Howard, B. , Rothenberger, K. S. , Cugini, A. V. , Morreale, B. D. , and Ciocco, M. V. , 2005, “ Uncatalyzed and Wall-Catalyzed Forward Water-Gas Shift Reaction Kinetics,” AIChE J., 51(5), pp. 1440–1454. [CrossRef]
Hou, K. , and Hughes, R. , 2001, “ The Kinetics of Methane Steam Reforming Over a Ni/α—Al2o Catalyst,” Chem. Eng. J, 82(1–3), pp. 311–328. [CrossRef]
Silean, A. , and Wang, T. , 2010, “ Effect of Turbulence and Devolatilization Models on Coal Gasification Simulation in an Entrained-Flow Gasifier,” Int. J. Heat Mass Transfer, 53(9–10), pp. 2074–2091. [CrossRef]
Lu, X. , and Wang, T. , 2011, “ Water-Gas Shift Modeling of Coal Gasification in an Entrained Flow-Gasifier,” 28th International Pittsburgh Coal Conference, Pittsburgh, PA, Sept. 12–15, Paper No. 45-1. http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.659.3991&rep=rep1&type=pdf
Poinsot, T. , and Veynante, D. , 2011, Theoretical and Numerical Combustion, 3rd ed., R. T. Edwards, Philadelphia, PA.
Rehm, M. , Seifert, P. , and Meyer, B. , 2009, “ Theoretical and Numerical Investigation on the Edc-Model for Turbulence Chemistry Interaction at Gasification Conditions,” Comput. Chem. Eng., 33(2), pp. 402–407. [CrossRef]
Kajitani, S. , Hara, S. , and Matsuda, H. , 2002, “ Gasification Rate Analysis of Coal Char With a Pressurized Drop Tube Furnace,” Fuel, 81(5), pp. 539–546. [CrossRef]

Figures

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Fig. 2

Vectors along the central plane and across a cross section in the middle of the combustor region

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Fig. 1

Mitsubishi heavy industries gasifier schematic

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Fig. 9

Time-scale variation of CH4 along the gasifier centerline

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Fig. 10

Time-scale variation of H2 along the gasifier centerline

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Fig. 3

Temperature contour along the central plane and across a cross section in the middle of the combustor region

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Fig. 4

Temperature along the gasifier centerline

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Fig. 11

Time-scale variation of CH4 on Z = 0.8 m transverse plane

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Fig. 12

Time-scale variation of H2 on Z = 2.6 m transverse plane

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Fig. 5

Time-scale variation of CO along the gasifier centerline

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Fig. 6

Time-scale variation of CO2 along the gasifier centerline

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Fig. 7

Time-scale variation of CO on Z = 0.8 m transverse plane

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Fig. 8

Time-scale variation of CO2 on Z = 2.6 m transverse plane

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Fig. 14

Representative coal track inside MHI gasifier

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Fig. 15

Char rates for R9

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Fig. 16

Char rates for R10

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Fig. 18

Char rates for R12

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Fig. 13

Time-scale variation of SVD scalars yir along the gasifier centerline

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