Turbulence Modelling on Fluidized Bed Gasification

Öz

Energy generation from carbon based solid materials, such as coal by a gasification process increasingly gets an essential research subject, as current energy sources getting to a close. Waste material management is also great significance to dispose them sustainably and efficiently from environment. There is, therefore, the need of advanced modelling approach to maximize the efficiency of coal-derived synthesis gas, and to optimize process parameters for designing a new gasifier. Hence, two-dimensional (2-D) gasification system was initially simulated by using commercial code ANSYS FLUENT. Devolatilization and char combustion chemical reactions of the process were modelled by User Defined Functions (UDF) to simulate their chemical kinetics more accurately. After mesh independency study and model validation performed, RANS based turbulence models were examined to find out best turbulence modelling approach. Performance evaluation was done and energy efficiency of the gasification system were also calculated.

Anahtar Kelimeler

• Solid waste material,Waste management,Gasification,Combustion,Turbulence,Modeling,CFD

Kaynakça

1. [1] Levendis A. Y., Atal A., Carlson B. J., Quintana M. M. E., 2001. PAH and Soot Emissions from Burning Components of Medical Waste: Examination/Surgical Gloves and Cotton Pads. Chemosphere, 42(5-7), pp. 775-783.
2. [2] Monteiro E., Couto N., 2015. Numerical and Experimental Analysis of Municipal Solid Wastes Gasification Process. Applied Thermal Engineering, 78, pp. 185-195.
3. [3] Mellin P., Kantarelis E., Zhou C., Yang W., 2014. Simulation of Bed Dynamics and Primary Products from Fast Pyrolysis of Biomass: Steam Compared to Nitrogen as A Fluidizing Agent. Industrial Engineering Chemistry Research, 53, pp. 12129-12142.
4. [4] Gunarathne S. D., Mueller A., Fleck S., Kolb T., Chmielewski J. K., Yang W., Blasiak W., 2014. Gasification Characteristics of Steam Exploded Biomass in An Updraft Pilot Scale Gasifie. Energy, 71, pp. 496-506.
5. [5] Horton R. S., Zhang Y., Bennett A. C., Klein T. M., Petrocelli F., 2016. Molecular-Level Kinetic Modeling of Biomass Gasification. Energy&Fuels 30, pp. 1647–1661.
6. [6] Pour S. M., Weihong Y., 2014. Performance of Pulverized Coal Combustion under High Temperature Air Diluted by Steam. ISRN Mechanical Engineering, 2014, pp. 217-227.
7. [7] Zhou C., Stuermer T., Gunarathne R., Yang W., Blasiak W., 2014. Effect of Calcium Oxide on High-Temperature Steam Gasification of Municipal Solid Waste. Fuel, 122, pp. 36-36.
8. [8] Li J., Bonvicini G., Tognotti L., Yang W., Blasiak W., 2014. High-Temperature Rapid Devolatilization of Biomasses with Varying Degree of Torrefaction. Fuel, 122, pp. 261-269.

9. [9] Kantarelis E., Yang W., Blasiak W., 2014. Effect of Zeolite to Binder Ratio on Product Yields and Composition During Catalytic Steam Pyrolysis of Biomass over Transition Metal Modified. Fuel, 122, pp. 119-125.
10. [10] Mellin P., Kantarelis E., Yang W., 2014. Computational Fluid Dynamics Modeling of Biomass Fast Pyrolysis in A Fluidized Bed Reactor, Using A Comprehensive Chemistry Scheme. Fuel, 117, pp. 704-715.
11. [11] Gunarathne S. D., Chmielewski K. J., Yang W., 2014. Pressure Drop Prediction of A Gasifier Bed with Cylindrical Biomass Pellets. Applied Energy, 113, pp. 258-266.
12. [12] Schulze S. A., Richter M., Vascellari A., Gupta B., Meyer P., Nikrityuk A., 2016. Novel Intrinsic-based Sub Model for Char Particle Gasification in Entrained-flow Gasifiers: Model Development, Validation and Illustration. Applied Energy, 164, pp. 805-814.
13. [13] ANSYS Inc., 2016. Modeling Heterogeneous Reactions with Eulerian-Granular Flow, pp. 16-25.
14. [14] Baruah D., Baruah D. C., 2014. Modeling of Biomass Gasification: A Review. Renewable and Sustainable Energy Reviews, 39, pp. 806-815.
15. [15] Addison K. S., Altantzis C., Bates R. B., Ghoniem A. F., 2016. Towards An Advanced Reactor Network Modeling Framework for Fluidized Bed Biomass Gasification: Incorporating Information from Detailed CFD Simulations, Chemical Engineering Journal, 303, pp. 409-424.
16. [16] Versteeg H. K., Malalasekera W., 2007. An Introduction to Computational Fluid Dynamics, 2nd ed., Pearson Education Limited, Harlow, England.
17. [17] Bakul C. E. J., Gershtein V. Y., Xianming L., 2001. Computational Fluid Dynamics in Industrial Combustion, 2nd ed., NY CRC Press, New York, US.
18. [18] FLUENT Inc., 2001. Introduction to Modelling Multiphase Flow, 18-12.
19. [19] Gunn D. J., 1978. Transfer of Heat or Mass to Particles in Fixed and Fluidized Beds. International Journal of Heat and Mass Transfer, 21, pp. 467-476.
20. [20] Liu H., 2014. CFD Modeling of Biomass Gasification Using A Circulating Fluidized Bed Reactor, Ph.D. Thesis, Waterloo University, Ontario, Canada.
21. [21] Couto N., Silva V., Monteiro E., Paulo Brito P., Rouboa A., 2015. Using An Eulerian-granular 2-D multiphase CFD Model to Simulate Oxygen Air Enriched Gasification of Agroindustrial Residues. Renewable Energy, 77, pp. 174-181.