THERMAL SCIENCE
International Scientific Journal
SULFUR SELF-RETENTION IN ASH A GRAIN MODEL APPROACH
ABSTRACT
A developed overall model for sulfur self-retention in ash during coal particle combustion is presented in the paper. The total sulfur content in char, after devolatilization, is evaluated using a derived correlation. It is assumed that sulfur retention during char combustion occurs due to the reaction between SO2 and the active part of the Ca in the form of uniformly distributed CaO grains. Parametric analysis shows that the process is limited by solid diffusion through the product layer formed on the CaO grains and that the most important coal characteristics which influence sulfur self-retention are coal rank, content of sulfur forms, molar Ca/S ratio and particle radius. The model predicts relatively well the levels of the experimentally obtained values of SSR efficiencies, as well as the influence of temperature, particle size and the surrounding conditions.
KEYWORDS
PAPER SUBMITTED: 2002-10-11
PAPER REVISED: 2002-11-15
PAPER ACCEPTED: 2002-11-17
THERMAL SCIENCE YEAR
2002, VOLUME
6, ISSUE
Issue 2, PAGES [29 - 46]
- Puff, R., Kita, J.-C., Large, J.-F., Feugier, A., Self-Desulfuration of High Sulfur High Ash Provence Coal by the Cerchar F.B.C. Process., Proc. of the 1st Int. FBC and Applied Techn. Symp., Beijing, China, (1983), pp. 22
- Raymant, A. P., Sulfur Capture by Coal Ash and Freeboard Processes During Fluidized Bed Combustion, Proc. of the 10th Int. Conf. on Fluidized Bed Combustion, San Francisco, USA, 1 (1989), pp. 597
- Fuertes, A. B., Artos, V., Pis, J. J., Marban, G., Palacios, J. M., Fuel, 71 (1992), 507
- Yeh, A. T., Lee, Y. Y., Genetti, W. E., Sulfur Retention by Mineral Matter in Lignite During Fluidized Bed Combustion, Proc. of the 12th Int. Conf. on Fluidized Bed Combustion, Boston, USA, 1 (1987), pp. 345
- Manovic, V., Grubor, B., Jovancicevic, B., Chemical Industry, 53 (1999), 107 (in Serbian)
- Grubor, B., Manovic, V., Arsic, B., Influence of Combustion Conditions and Coal Characteristics on Self-Retention of SO2 by Ash Itself, Proc. of the Mediteraanean Combustion Symposium, MCS-99, Antala, Turkey, (1999), pp. 866
- Gray, V. R., Fuel, 65 (1986), 1618
- Sheng, C., Xu, M., Zhang, J., Xu, Y., Fuel Process. Technol., 64 (2000), 1
- Chen, C., Kojima, T., Fuel Process. Technol., 53 (1997), 49
- Uzun, D., Ozdogan, S., Fuel, 77 (1998), 1599
- Uzun, D., Ozdogan, S., Fuel, 76 (1997), 995
- Gryglewicz, G., Fuel, 74 (1995), 356
- Manovic, V., Grubor, B., Behaviour of Sulfur Forms During Devolatilization of Coal, Proc. of the 3rd Symp. of South-East European Countries (SEEC) on Fluidized Beds in Energy Production, Chemical and Process Engineering and Ecology, Sinaia, Romania, (2001), pp. 57
- Ilic, M., Grubor, B., Manovic, V., J. Serb. Chem. Soc. (submitted)
- Ilic, M., Oka, S., Grubor, B., Thermal Science, 2 (1998), 61
- Smith, I.W., Fuel, 57 (1978), 409
- Arthur, J., Trans. Faraday Soc., 47 (1951), 164
- Scholer, J., Ein Gesamtmodell fur Dampferzeugeranlangen mit Zirkulierender Wirbelschichtfeuerung, Ph. D. Thesis, Siegen University, Germany, (1992)
- Bhatia, S., Perlmutter, D., AIChE J., 26 (1980), 379
- Grubor, B., Manovic, V., Energy & Fuels, 16 (2002), 951
- Allen, D., Hayhurst, A. N., J. Chem. Soc., Faraday Trans., 92 (1996), 1227
- Anthony, E. J., Granatstein, D. L., Progr. in Energy and Comb. Sci., 27 (2001), 215
- Adanez, J., Gayan, P., de Diego, L. F., Chem. Eng. Sci., 51 (1996), 3077
- Li, X., Luo, Z., Ni, M., Cen, K., Chem. Eng. Sci., 50 (1995), 2235
- Marsh, D. W., Ulrichson, D. L., Chem. Eng. Sci., 40 (1985), 423
- Borgwardt, R. H., Bruce, K. R., Blake, J., Ind. Eng. Chem. Res., 26 (1987), 1993
- Hartman, M., Coughlin, R. W., AIChE J., 22 (1976), 490
- Lyngfelt, A., Leckner, B., Chem. Eng. Sci., 44 (1989), 207
- Hartman, M., Trnka, O., Chem. Eng. Sci., 35 (1980), 1189
- Patankar, S.V., Numerical Heat Transfer and Fluid Flow, Hemisphere Publishing Corp., USA, 1980
- Gryglewicz, G., Fuel Process. Technol., 46 (1996), 217
- Bhatia, S. K., Perlmutter, D. D., AIChE J., 27 (1981), 226
- Diaz-Bosio, L. M., Squier, S. E., Pulsifer, A. H., Chem. Eng. Sci., 40 (1985), 319