A METHOD TO DETECT AND CONTROL FULLY FLUIDIZED CONICAL BEDS WITH A WIDE SIZE DISTRIBUTION OF PARTICLES IN THE VICINITY OF THE MINIMUM FLUIDIZATION VELOCITY
Abstract
This article presents a new method for the control of a gas-sand conical fluidized bed with a wide size distribution of particles. A two-step procedure was developed and experimentally tested. The minimum velocity for full fluidization is determined by a new statistically based method and then the fully fluidized state is initiated and controlled. It is proven that the characteristics of the pressure drop vs. fluidization velocity remain practically the same for different bed heights and over a wide size distribution of particles. The method analyses the recorded pressure drops with a histogram. The minimum velocity for full fluidization is determined as the smallest fluidization velocity from the histogram bin with the highest density. Finally, it is also proved that the fluidization velocity is a reliable parameter for controlling the fluidization. The method was used to control fully fluidized beds at the minimum gas velocity in a pilot FICFB gasificator.
Dates
- Submission Date2013-06-27
- Revision Date2013-11-04
- Acceptance Date2013-11-26
- Online Date2013-12-22
References
- Kwauk, M., Fluidization, Science and Press, New York, 1992
- Kunii, D., Levenspiel, O., Fluidization Engineering, Butterworth-Heinemann, inc., 1991
- Simeon N. Oka, Fluidized bed combustion, ISBN: 0-8247-4699-6, Marcel Dekker, Inc., New York, Basel, September 2004
- Jing, S., Hu, Q., Wang, J., Jin., Y., Fluidization of coarse particles in gas-solid conical beds, Chemical engineering and Processing, 39 (2000), pp. 379-387
- Kaewklum, R., Kuprianov, V. I., Theoretical and experimental study on hydrodynamic characteristic of fluidization in air-sand conical beds, Chemical Engineering Science, 63 (2008), pp. 1471-1479
- Löffler, G., Kaiser, S., Bosch, K., Hofbauer, H., Hydrodynamics of a Dual Fluidized - Bed Gasifier - Part I : Simulation of a Riser With Gas Injection and Diffuser, Chemical Engineering Science, 58 (2003), pp. 4197- 4213
- Girimonte, R., Formisani, B., The minimum bubbling velocity of fluidized beds operating at high temperature, Powder Technology, 189 (2009), pp. 74-81
- Johnsson, F., Zijerveld, R. C., Schouten, J. C., Van den Bleek, C. M., Leckner, B., Characterization of fuidization regimes by time-series analysis of pressure fluctuations, International Journal of Multiphase Flow, 26 (2000), pp. 663-715
- Langde, A. M., Sonolikar R. L., Tidke D. J., The influence of acoustic field and frequency on hydrodynamics of group b particles, Thermal science, 15 (2011), 1, pp. 159-168
- Zhang, Y., Jin, B., Zhong, W., Experimental investigation on mixing and segregation behaviour of biomass particle in fluidized bed, Chemical Engineering and Processing, 48 (2009), pp. 745-754
- Dziubakowski, D. J., Smith, J. W., Control system for a fluidized bed, U.S. Patent 4593477, filed Jan 14, 1985 and issued Jun 10, 1986
- Suzuki, T., Hirose, R., Ishizuka, H., Kai, F., Morita, A., Yano, K., Process for detecting state of fluidized bed, Japanese patent JP01168335, filed Dec 23, 1987 and issued July 03, 1989
- Van Ommen, J. R., Sasic, S., Van der Schaaf, J., Gheorghiu, S., Johnsson, F., Coppens, M. O., Time-series analysis of pressure fluctuations in gas-solid fluidized beds - A review, International Journal of Multiphase Flow, 37 (2011), pp. 403-428
- Parise, M. R., Taranto, O. P., Kurka, P. R. G., Benetti, L. B., Detection of the minimum gas velocity using Gaussian spectral pressure distribution ain a gas-solid fluidized bed, Powder technology, 182 (2008), pp. 453-458
- Parise, M. R., Kurka, P. R. G., Taranto, O. P., The gaussian spectral pressure distribution applied to a fluidized bed, Chemical Engineering and Processing, 48 (2009), pp. 120-125
- Parise, M. R., Silva, C. A. M., Ramazini, M. J., Taranto, O. P., Identification of defluidization in fluidized bed coating using the Gaussian spectral pressure distribution, Powder Technology, 206 (2011), pp. 149-153
- Van Ommen, J. R., Korte, R. J. D., Van den Bleek, C. M., Rapid detection of defluidization using the standard deviation of pressure fluctuations, Chemical Engineering and Processing, 43 (2004), pp. 1329-1335
- Felipe, C. A. S., Rocha, S. C. S., Prediction of minimum fluidization velocity of gas-solid fluidized beds by pressure fluctuation measurements - Analysis of the standard deviation methodology, Powder technology, 147 (2007), pp. 104-113
- Puncochar, M., Drahos, J., Cermak, J., Selucky, K., Evaluation of minimum fluidizing velocity in gas fluidized bed from pressure fluctuations, Chemical Engineering Communications, 35 (1985), pp. 81-87
- Jiliang, M., Xiaoping, C., Daoyin, L., Minimum fluidization velocity of particles with wide size distribution at high temperatures, Powder Technology, 235 (2013), pp. 271-278
- Schuster, G., Loffler, G., Weigl, K., Hofbauer, H., Biomass steam gasification - an extensive parametric modeling study, Bioresourse Technology, 77 (2001), pp. 71-79
- Cotton, A., Patchigolla, K., Oakey, J. E., Hydrodynamic characteristics of a pilot-scale cold model of a CO2 capture fluidised bed reactor, Powder Technology, 235 (2013), pp. 1060-1069
- Pirc, A., Sekavčnik, M., Mori, M., Universal model of a biomass gasifier for different syngas compositions, Strojniški vestnik - Journal of Mechanical Engineering, 58 (2012), pp. 291-299
- Ćojbašić, Ž. M., Nikolić, V. D., Ćirić, I. T., Ćojbašić, L. R., Computationally intelligent modelling and control of fluidized bed combustion process, Thermal science, 15 (2011), pp. 321-338
Volume
19,
Issue
1,
Pages267 -276