Hydrodynamics in an Airlift Inner-loop Three-phase Biological Fluidized Bed

In order to meet the demand of developing a wastewater treatment, the hydrodynamics, such as gas holdup, cycle time, uniform mixing time, and volumetric mass transfer coefficient of oxygen, were studied in this article. When gas velocity is 200 L/h and solid holdup is 6%, the gas holdup is 21.8%. When gas velocity is 180 L/h and solid holdup is 5%, the liquid cycle time is 8 sec. When gas velocity is 240 L/h and solid holdup is 3%, the liquid uniform mixing time is 31 sec. When gas velocity is 200 L/h and solid holdup is 5%, the volumetric mass transfer coefficient of oxygen KLa is 23.37 min−1. Meanwhile, oily wastewater was studied to verify the reliability of hydrodynamics’ performance in the reactor, where chemical oxygen demand and total petroleum hydrocarbon removal are up to 96.39 and 96.43%, respectively, when gas velocity is 180 L/h and the solid holdup is 3–5%.