Pulsating flow effect on the segregation of binary particles in a gas-solid fluidized bed

Air pulsation effect on the segregation efficiency of mixed binary particles in fluidized beds was studied in this research. Experiments were conducted to investigate pulsed fluidizing effect on two dissimilar sizes of silicon dioxide including flotsam and jetsam particles. A cylindrical bed with 11 cm diameter and 50 cm height was employed to examine different effective parameters on the segregation process. A solenoid valve was employed to pulsate the airflow with 1, 2, and 4 Hz frequencies. Inlet air was applied to the initially mixed bed particles at three different configurations including continuous, combined, and pure pulsed configurations. In addition to these three configurations, the effects of air velocity and particle compositions were investigated. With the fixed flow rate, significant increase in the segregation efficiency achieved by changing continuous to pulsed inlet air. The results indicated that in addition to increase in the magnitude, the rate of the segregation increased considerably. Higher peak of the applied velocity and eliminating dead zones and channel-like structures are the reasons of improvement in segregating of binary particles in pulsed fluidized bed. Hence, the air pulsation is as an efficient tool to enhance the segregation process of dissimilar particles. (C) 2014 Elsevier B.V. All rights reserved.