NUMERICAL SIMULATION OF NON-CONVENTIONAL LIQUID FUELS FEEDING IN A BUBBLING FLUIDIZED BED COMBUSTOR

Abstract

The paper deals with the development of mathematical models for detailed simulation of lateral jet penetration into the fluidized bed (FB), primarily from the aspect of feeding of gaseous and liquid fuels into FB furnaces. For that purpose a series of comparisons has been performed between the results of in-house developed procedure- fluid-porous medium numerical simulation of gaseous jet penetration into the fluidized bed, Fluent's two-fluid Euler-Euler FB simulation model, and experimental results (from the literature) of gaseous jet penetration into the 2D FB. The calculation results, using both models, and experimental data are in good agreement. The developed simulation procedures of jet penetration into the FB are applied to the analysis of the effects, which are registered during the experiments on a fluidized pilot furnace with feeding of liquid waste fuels into the bed, and brief description of the experiments is also presented in the paper. Registered effect suggests that the water in the fuel improved mixing of fuel and oxidizer in the FB furnace, by increasing jet penetration into the FB due to sudden evaporation of water at the entry into the furnace. In order to clarify this effect, numerical simulations of jet penetration into the FB with three-phase systems: gas (fuel, oxidizer, and water vapour), bed particles and water, have been carried out.

Dates

  • Submission Date2012-11-16
  • Revision Date2012-12-10
  • Acceptance Date2012-12-24
  • Online Date2013-01-20

DOI Reference

10.2298/TSCI121116007M

References

  1. Saxena S. C., Jotshi C. K., Fluidized bed incineration of waste materials, Progress in Energy and Combustion Science, 20 (1994), 4, pp. 281-324 dx.doi.org/10.1016/0360-1285(94)90012-4
  2. Link, J.M. et al., Flow regimes in a spout-fluid bed:Acombined experimental and simulation study, Chemical Engineering Science, 60 (2005), 13, pp. 3425-3442.
  3. Utikara, R.P., Ranade, V.V., Single jet fluidized beds: Experiments and CFD simulations with glass and polypropylene particles, Chemical Engineering Science, 62 (2007), 1-2, pp. 167-183 dx.doi.org/10.1016/j.ces.2006.08.037
  4. Di Renzo, A., Di Maio, F.P., Homogeneous and bubbling fluidization regimes in DEM-CFD simulations: Hydrodynamic stability of gas and liquid fluidized beds, Chemical Engineering Science, 62 (2007), 1-2, pp. 116-130 dx.doi.org/10.1016/j.ces.2006.08.009
  5. Enwald, H. et al., Simulation of the fluid dynamics of a bubbling fluidized bed. Experimental validation of the two-fluid model and evaluation of a parallel multiblock solver, Chemical Engineering Science, 54 (1999), 3, pp. 311-328 dx.doi.org/10.1016/S0009-2509(98)00186-9
  6. Nemoda, S. et al., Numerical model of gaseous fuel jet injection into a fluidized furnace, International Journal of Heat and Mass Transfer, 52 (2009), 15-16, pp. 3427-3438 dx.doi.org/10.1016/j.ijheatmasstransfer.2009.02.045
  7. Hong, R. et al., Studies on the inclined jet penetration length in a gas-solid fluidized bed, Powder Technology, 92 (1997), 3, pp. 205-212.
  8. Davidson, J.F., Cliff R., Harrison D. (eds.), Fluidization, Academic Press, London, 2nd edn., 1985.
  9. Patankar S.V., Numerical Heat Transfer and Fluid Flow, Hemisphere, New York, 1980.
  10. Patankar S.V., Spalding, D.B., A calculation procedure for heat, mass and momentum transfer in three-dimensional parabolic flows, Int. Journal of Heat and Mass Transfer, 15 (1972), 10, pp.1787-1806 dx.doi.org/10.1016/0017-9310(72)90054-3
  11. Vejahati, F. et al., CFD Simulation of Gas-Solid Bubbling Fluidized Bed: A New Method for Adjusting Drag Law, Can. J. Chem. Eng., 87 (2009), pp.19-30.
  12. Syamlal, M., Rogers, W., O'Brien, T.J., MFIX Documentation Theory Guide, U.S. Department of Energy, Office of Fossil Energy Morgantown Energy Technology Center, Morgantown, WV (1993).
  13. Lun, C. K. K. et al., Kinetic Theories for Granular Flow: Inelastic Particles in Couette Flow and Slightly Inelastic Particles in a General Flow Field, Journal of Fluid Mechanic., 140 (1984), pp. 223-256 dx.doi.org/10.1017/S0022112084000586
  14. Schaeffer, D. G., Instability in the Evolution Equations Describing Incompressible Granular Flow, J. Diff. Eq., 66 (1987), 1, pp.19-50 dx.doi.org/10.1016/0022-0396(87)90038-6
  15. Syamlal, M., O'Brien, T. J., Simulation of Granular Layer Inversion in Liquid Fluidized Beds, International Journal of Multiphase Flow, 14 (1988), 4, pp. 473-481 dx.doi.org/10.1016/0301-9322(88)90023-7
  16. Shakhova, N.A., Discharge of turbulent jets into a fluidized bed, Journal of Engineering Physics and Thermophysics, 14 (1968), 1, pp. 32-36.
  17. Zenz, F.A., Bubble formation and grid design, IChemE Symposium Series, 30 (1968), pp. 136-139.
  18. Merry, J.M.D., Penetration of a horizontal gas jet into a fluidised bed, Transactions of the Institution of Chemical Engineers and the Chemical Engineer, 49 (1971), 4, pp. 189-195.
  19. Kozin B. E., Baskakov, A. P., Studies on the jet range in a bed of granular particles, Khim I Teckhnol Topliv I Masel, 3 (1967), pp. 4-7.
  20. Yates, J. G., Cobbinah, S. S., Cheesman D. J., Jordan, S. P., Particle Attrition in Fluidized Beds Containing Opposing Jets, AIChE Symp. Ser., 281 (1988), pp. 13-19.
  21. Benjelloun, F., Liegeois, R., Vanderschuren, J., Penetration Length of Horizontal Gas Jets into Atmospheric Fluidized Beds, Proc. Fluidization-VIII (J-F. Large and C. Laguerie, Eds.), Engineering Foundation, N.Y., 1995, pp. 239-246.
  22. Mladenović M. R. et al., Vertical temperature profile in the installation for the combustion of waste fuels in the fluidized bed furnace, Proceedings, 15th Symposium on Thermal Science and Engineering of Serbia, Sokobanja, Serbia, October 18-21, 2011, Conference proceedings on CD-ROM, ISBN 978-86-6055-018-9, pp. 490-499.
  23. Mladenović, M. R., et al., Vertical temperature profile in the installation for the combustion of waste fuels in the fluidized bed furnace (in Serbian language: Vertikalni profil temperature u instalaciji za sagorevanje otpadnih goriva sa fluidizovanim slojem), Termotehnika, XXXVIII (2012), 1, pp. 11-24.
  24. Mladenović, M. R., et al., Combustion of low grade fractions of Lubnica coal in fluidized bed, Thermal Science, 16 (2012), 1, pp. 297-311 dx.doi.org/10.2298/TSCI1201297M
  25. Brennan, J. F., Shapiro, J. S., Watton, E. C., Evaporation of liquids: A kinetic approach, J. Chem. Educ., 51 (1974), 4, p. 276.
Volume 17, Issue 4, Pages1163 -1179