Study of Aerated Fluidized Bed Treatment of Wastewater Containing Cd2+ and Simulation of Flow Field of Internal Circulation System

Abstract

Using the computational fluid dynamic numerical simulation method, the gas, liquid, and solid three-phase hydrodynamic behavior in a self-made aeration fluidized bed reactor was simulated numerically. The influence of gas inlet velocity and solid phase volume on gas holdup, solid holdup, and liquid circulation velocity in the reactor were studied. Treatment of Cd2+ wastewater by the self-made fluidized bed showed that when inlet velocity was 0.3 m/s and adsorbent dosage was 9.5%, the adsorption effect was the best, and the adsorption rate was 63.5%. Simulation results verified the experimental conclusions and clarified the interaction of the three phases of gas, liquid, and solid in the fluidized bed treatment of wastewater. The higher the air inlet speed, the lower was the solid content rate and the greater was the liquid circulation speed; at the same air inlet speed, the larger the solid phase volume, the higher was the solid content rate, the smaller was the solid phase volume, the greater was the liquid circulation speed, the higher was the gas holdup rate, and the higher was the utilization rate.