Gas-liquid dispersion characteristics in a stirred tank equipped with porous aeration tube

• • For both HEDT and WH impellers, the critical Froude number (Fr) decreased significantly with increasing gas flow number (FlG), indicating that higher gas flow rates facilitate complete dispersion at lower impeller speeds, which can reduce energy consumption in industrial operations. • • At L/D = 0.75, the optimal impeller installation height, overall gas holdup was maximized while power consumption was minimized, achieving a balance between mass transfer efficiency and energy savings. • • The HEDT impeller exhibited a higher relative power demand (RPD) than the WH impeller under identical conditions, meaning its agitation power was less affected by gas introduction, making it more suitable for high-speed gas-liquid dispersion operations. • • The porous tube sparger improved bubble distribution uniformity and gas-liquid mixing efficiency, leading to enhanced mass transfer rates compared to conventional spargers, as evidenced by higher gas holdup at equivalent power inputs.