EXPERIMENTAL STUDY ON FLOW CHARACTERISTICS OF CATALYST PARTICLES IN INCLINED PIPE WITH NEGATIVE PRESSURE GRADIENT

Abstract

Abstract: On the Φ150mm×3600mm negative pressure gradient tube-valve experimental device,the characteristicparameters of the axial dynamic pressure in the inclined tube with different catalyst particle mass flow rates (G_s) were measured and analyzed,and the flow characteristics of catalyst particles in inclined tube of FCC unit were studied. The results showed that the pressure storage capacity of the inclined pipe increased with the increase of particle mass flow rate Gs and the lean phase stratified flow and dense phase stratified flow appeared successively in the pipe.The pressure distribution, dominant frequency, amplitude and pressure variance in the inclined tube correspond to the flow pattern, which could be used for quantitative identification of the flow pattern. When G_s＝65.96 kg/(m².s), there were multiple flow patterns in the inclined pipe, including transition packed-bed flow, packed-bed flow and dense phase flow. The aeration gas was injected into the middle of the inclined pipe to effectively improve the particle conveying capacity and the pressure storage capacity of the inclined pipe.

Key words: catalytic cracking, inclined pipe, flow pattern, dynamic pressure, aeration gas

References

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