Jaber Shabanian, Pierre Sauriol, and Jamal Chaouki has recently published a research article in the Chemical Engineering Journal. A novel approach was introduced for the early detection of defluidization conditions in a bubbling gas-solid fluidized bed. The new approach benefits from its simplicity, effectiveness, and robustness with respect to the variation of influential operating parameters, i.e., bed temperature, superficial gas velocity, and bed inventory.
Below you can find the abstract:
This study presents a simple approach for the early detection of agglomeration in a bubbling gas-solid fluidized bed. This monitoring approach is based on the simultaneous measurements of local temperatures and the in-bed differential pressure drop from the well-stabilized section of the bed. Defluidization experiments (800–1000oC) showed that when a bubbling gas-solid fluidized bed approaches complete defluidization the average in-bed differential pressure drop progressively decreases from a reference value obtained under normal conditions while the temperature difference along the axis, particularly between a temperature reading right above the distributor plate and others at higher levels within the dense bed, simultaneously increases. This novel approach was thus proposed for the concurrent occurrence of these drifts to provide an opportune recognition of the onset of agglomeration in a bubbling gas-solid fluidized bed. The results demonstrated that it could effectively detect the defluidization condition minutes to hours before the complete defluidization state depending on the growth rate of agglomeration within the bed. Two pairs of detection thresholds for the timely recognition of agglomeration in bubbling fluidized beds of coarse silica sand particles were introduced according to the observations made in this study. The approach exhibited minimal sensitivity to variations in the superficial gas velocity (±10%), operating temperature (±100oC), and bed inventory (±20%) while both legs of the in-bed differential pressure transducer were well below the splash zone and above the jetting zone formed in the vicinity of the distributor plate.