TY - JOUR ID - 7425 TI - Hydrodynamic Characterization of Three-Phase Fluidized-Beds Using Vibration Signature Analysis JO - Nashrieh Shimi va Mohandesi Shimi Iran JA - NSMSI LA - en SN - 1022-7768 AU - Sheikhi, Amir AU - Sotudeh-Gharebagh, Rahmat AU - Mostoufi, Navid AU - Zarghami, Reza AU - Mahjoob Jahromi, Mohammad AD - Multiphase Systems Research Lab., Oil and Gas Processing Centre of Excellence, School of Chemical Engineering, College of Engineering, University of Tehran, P.O. Box 11155-4563 Tehran,, I.R. IRAN AD - Modal Lab. School of Mechanical Engineering, College of Engineering, University of Tehran, Tehran, I.R. IRAN Y1 - 2012 PY - 2012 VL - 30 IS - 4 SP - 43 EP - 53 KW - Three-phase fluidized bed KW - Hydrodynamics KW - Vibration fluctuation KW - Minimum fluidization KW - statistical analysis DO - N2 - Vibration fluctuations of a three-phase gas-liquid-solid fluidized-bed, as a novel method of hydrodynamic characterization of such a complex system, were introduced and investigated. The studied three-phase fluidized-bed consisted of air, water, and sand particles as three operating phases, in which, water was continuous, and air and sand particles were dispersed phases, respectively. Such fluidized-beds, in which, the gas and liquid are upward co-current flows, and solid is present from the beginning of the process, are known as the most common industrial three-phase fluidized-beds. Using reliable, yet non-intrusive methods to study the hydrodynamics of such systems is vital. In this paper, time-series obtained from vibration fluctuations signals at a height of 13.5 cm (L/D = 1.5) above the gas-liquid distributor were analyzed at time domain (statistical methods), as a usual method. Also, average cycle frequency, as a novel method to characterize such systems, was introduced. It was concluded that standard deviation of bed-shell vibration fluctuations is a powerful representative of bed overall regime change, and the change of the slope of kurtosis is occurring near minimum fluidization. Moreover, minimum liquid-fluidization velocity was acquired using average cycle frequency of vibration signals with an acceptable relative error. Operating condition, resulted by vibration analysis, at which the bed-regime change occurred, was in agreement with experimental observations, and the results of minimum fluidization were consistent with the most accurate relations in the literature. Finally, vibration signature analysis, as a fully-non-invasive method which doesn’t interfere with internal hydrodynamics of the bed, is introduced to hydrodynamic characterization of three-phase fluidized beds. Outline of present research can be used in industrial reactors operated at sever conditions of temperature and/or pressure successfully. UR - https://www.nsmsi.ir/article_7425.html L1 - https://www.nsmsi.ir/article_7425_eaa44575173bfa5d6b2f949d9ddad060.pdf ER -