In chemical production processes, many operations such as oxidation and hydrogenation rely on the mass transfer efficiency of stirred tanks in terms of gas dispersion. Therefore, optimizing gas dispersion characteristics is a key issue. This study aimed to investigate the effects of impeller type, impeller position, and operating parameters on gas-liquid dispersion in a stirred tank by means of porous tube aeration, where two typical wide hydrofoil (WH) and half-elliptical disk turbine (HEDT) impellers were used to investigate the influence of impeller position and rotational speed on the gas dispersion. The critical rotational speed for complete gas dispersion, agitation power consumption, and overall gas holdup were clarified. It was found that for both HEDT and WH impellers, the critical Froude number (Fr) decreased significantly with increasing gas flow number (FlG). Under the same gassing rate, the critical complete dispersion Froude number of the HEDT impeller was generally higher than that of WH impeller, and also the agitation power required for complete dispersion was greater. Additionally, relative power demand (RPD) decreased as FlG increased, and this decreasing trend accelerated at higher L/D ratios. At different impeller positions, the relative power demand of the HEDT impeller was higher than that of the WH impeller, indicating that the agitation power of the HEDT impeller was less affected by the gas than the WH impeller. Notably, the impeller installation height had an obvious impact on gas holdup and power consumption. When the ratio of the vertical distance between the impeller center and the upper edge of the porous distributor (L) to the impeller diameter (D) was 0.75, a higher gas holdup and lower power comsuption were observed. This work provides crucial theoretical and data support for optimizing the design of gas-liquid stirred tanks with gas sparging. It holds clear engineering application value for enhancing mass transfer efficiency and energy-saving operation in chemical processes.