Comparison and Analysis of Pressure Fluctuation in a Fluid Catalytic Cracking and Mixed Particle Fluidized Bed

Transient signals of pressure fluctuation are recorded in a gas-solid fluidized bed dealing with fluid catalytic cracking (FCC) particles and binary mixed SiO₂and FCC particles, respectively. Both statistical analysis method and scale decomposition analysis methods are applied to obtain the hydrodynamic characteristics of the two kinds of particles. The bubble frequency obtained by the wavelet analysis method can accurately respond to the frequency of bubbles in the bed. The proportional coefficient related to the bubble size and differential pressure fluctuation is estimated, which is helpful to estimate the bubble size with the pressure fluctuation signals. Direct measurement data by optical fibers were applied and compared to support the analysis results of pressure fluctuations. The role of fine particles in improving fluidization quality during fluidization is also indicated.