Analysis of Changes on Mean Particle Size in a Fluidized Bed using Vibration Signature

Document Type : Research Paper

Authors

Multiphase Systems Research Group, School of Chemical Engineering, College of Engineering, University of Tehran, Tehran, Iran

Abstract

Vibration signals were measured in a lab-scale fluidized bed to investigate the changes in particle sizes. Experiments were carried out in the bed with a different mass fraction of coarser particles at different superficial gas velocities, and probe heights. The S-statistic test evaluates the dimensionless squared distance between two attractors reconstructed from time series of vibration signals. Values of parameters needed for the attractor reconstruction were derived from time series. These parameters consist of time delay, embedding dimension, bandwidth, and segment length with the values of 1, 35, (0.4-0.8), and (300-400), respectively. To reduce the sensitivity of the S-statistic to small changes in superficial gas velocities, the vibration signals were normalized in order to apply the attractor comparison test. The results showed that the attractor comparison can be a reliable technique for detecting particles size changes in fluidized beds even with small changes in the amount of coarser particles. The sensitivity of the method to particle size changes was decreased with an increase in superficial gas velocity. The results also show that the S-statistic test was almost independent of the measurement position of the vibration signals.

Keywords


[1] Bartels M, Lin W, Nijenhuis J, Kapteijn F, Van Ommen JR. Agglomeration in fluidized beds at high temperatures: Mechanisms, detection and prevention. Progress in Energy and Combustion Science. 2008 Oct 1;34(5):633-66.
[2] Tardos G, Mazzone D, Pfeffer R. Destabilization of fluidized beds due to agglomeration part I: Theoretical model. The Canadian Journal of Chemical Engineering. 1985 Jun;63(3):377-83.
[3] Tardos G, Mazzone D, Pfeffer R. Destabilization of fluidized beds due to agglomeration part I: Theoretical model. The Canadian Journal of Chemical Engineering. 1985 Jun;63(3):377-83.
[4] J. Seville, R. Clift, The effect of thin liquid layers on fluidisation characteristics, Powder Technology, 37 (1984) 117-129.
[5] van Ommen JR, Coppens MO, van den Bleek CM, Schouten JC. Early warning of agglomeration in fluidized beds by attractor comparison. AIChE Journal. 2000 Nov;46(11):2183-97.
[6] Zarghami R. Conditional monitoring of fluidization quality in fluidized beds. Ph. D. Dissertation, University of Tehran. 2009.
[7] Bai D, Bi HT, Grace JR. Chaotic behavior of fluidized beds based on pressure and voidage fluctuations. AIChE Journal. 1997 May;43(5):1357-61.
[8] Kai T, Furusaki S. Methanation of carbon dioxide and fluidization quality in a fluid bed reactor—the influence of a decrease in gas volume. Chemical engineering science. 1987 Jan 1;42(2):335-9.
[9] Schouten JC, van den Bleek CM. Monitoring the quality of fluidization using the short‐term predictability of pressure fluctuations. AIChE Journal. 1998 Jan;44(1):48-60.
[10] Chong YO, O'dea DP, White ET, Lee PL, Leung LS. Control of the quality of fluidization in a tall bed using the variance of pressure fluctuations. Powder technology. 1987 Dec 15;53(3):237-46.
[11] van Ommen JR, Schouten JC, van den Bleek CM. An early-warning-method for detecting bed agglomeration in fluidized bed combustors. Delft University of Technology (NL); 1999 Jul 1.
[12] Bartels M, Nijenhuis J, Kapteijn F, Van Ommen JR. Detection of agglomeration and gradual particle size changes in circulating fluidized beds. Powder Technology. 2010 Aug 25;202(1-3):24-38.
[13] Abbasi M, Sotudeh‐Gharebagh R, Mostoufi N, Zarghami R, Mahjoob MJ. Nonintrusive characterization of fluidized bed hydrodynamics using vibration signature analysis. AIChE Journal. 2010 Mar;56(3):597-603.
[14] Azizpour H, Sotudeh-Gharebagh R, Zarghami R, Abbasi M, Mostoufi N, Mahjoob MJ. Characterization of gas–solid fluidized bed hydrodynamics by vibration signature analysis. International Journal of Multiphase Flow. 2011 Sep 1;37(7):788-93.
[15] Book G, Albion K, Briens L, Briens C, Berruti F. On-line detection of bed fluidity in gas–solid fluidized beds with liquid injection by passive acoustic and vibrometric methods. Powder technology. 2011 Jan 10;205(1-3):126-36.
[16] Staniforth JN, Quincey SM. Granulation monitoring in a planetary mixer using a probe vibration analysis technique. International journal of pharmaceutics. 1986 Oct 1;32(2-3):177-85.
[17] Diks C, Van Zwet WR, Takens F, DeGoede J. Detecting differences between delay vector distributions. Physical Review E. 1996 Mar 1;53(3):2169.
[18] Shiea M, Sotudeh-Gharebagh R, Azizpour H, Mostoufi N, Zarghami R. Predicting transition velocities from bubbling to turbulent fluidization by S-statistics on vibration signals. Particulate Science and Technology. 2013 Jan 1;31(1):10-5.
[19] Wen CY, Yu YH. A generalized method for predicting the minimum fluidization velocity. AIChE Journal. 1966 May 1;12(3):610-2.
[20] Bi HT, Grace JR. Effect of measurement method on the velocities used to demarcate the onset of turbulent fluidization. The Chemical Engineering Journal and the Biochemical Engineering Journal. 1995 May 1;57(3):261-71.
[21] Ruelle D. The Claude Bernard Lecture, 1989-Deterministic chaos: the science and the fiction. Proceedings of the Royal Society of London. A. Mathematical and Physical Sciences. 1990 Feb 8;427(1873):241-8.
[22] Johnsson F, Zijerveld RC, Schouten JV, Van den Bleek CM, Leckner B. Characterization of fluidization regimes by time-series analysis of pressure fluctuations. International journal of multiphase flow. 2000 Apr 1;26(4):663-715.
[23] Zarghami R, Mostoufi N, Sotudeh-Gharebagh R. Nonlinear characterization of pressure fluctuations in fluidized beds. Industrial & Engineering Chemistry Research. 2008 Nov 5;47(23):9497-507.
[24] Takens F. Detecting strange attractors in turbulence. InDynamical systems and turbulence, Warwick 1980 1981 (pp. 366-381). Springer, Berlin, Heidelberg.
[25] Van der Schaaf J, Schouten JC, Van den Bleek CM. Origin, propagation and attenuation of pressure waves in gas—solid fluidized beds. Powder Technology. 1998 Mar 1;95(3):220-33.
[26] Addison PS. Fractals and chaos: an illustrated course. CRC Press; 1997 Jan 1.
[27] Theiler J. Spurious dimension from correlation algorithms applied to limited time-series data. Physical review A. 1986 Sep 1;34(3):2427.
[28] Kantz H, Schreiber T. Nonlinear time series analysis. Cambridge university press; 2004.
[29] Tamadondar MR, Zarghami R, Azizpour H, Mostoufi N, Chaouki J, Radmanesh R. Using S-statistic for investigating the effect of temperature on hydrodynamics of gas–solid fluidization. Particuology. 2013 Jun 1;11(3):288-93.
[30] Fraser AM, Swinney HL. Independent coordinates for strange attractors from mutual information. Physical review A. 1986 Feb 1;33(2):1134.
[31] Azizpour H, Hadadi-Sisakht B, Norouzi HR, Sotudeh-Gharebagh R, Zarghami R, Mostoufi N. Detecting sudden changes in fluidization by wall vibration. Particulate Science and Technology. 2014 Jul 4;32(4):412-7.
[32] Azizpour H, Sotudeh-Gharebagh R, Mostoufi N, Zarghami R. Characterization of regime transition in fluidized beds at high velocities by analysis of vibration signals. Industrial & Engineering Chemistry Research. 2012 Feb 10;51(7):2855-63