Mass Transfer and Multiphase Flow of Long‐Arm Pitched Paddle Impeller at High Gas Flow Rates

This study examines gas–liquid stirred tanks using Rushton‐type and long‐armed pitched paddle (LAPP) impellers at 0.35–1.1 VVM. Particle image velocimetry revealed up to 42% reductions in turbulent kinetic energy and radial velocity at high aeration from bubble–liquid interactions. The LAPP achieved up to 41% higher mass transfer coefficients than the Rushton at similar P g / V , showing superior energy efficiency. Aerated power draw and flow regime transitions were correlated with Froude and aeration numbers, and a generalized correlation for mass transfer coefficients was developed from P g / V and aeration number. Results support improved design and scale‐up of gas–liquid reactors, emphasizing the benefits of advanced impeller geometries.