Impact of HSPBT Blade Angle on Gas Phase Hydrodynamics in a Gas–Liquid Stirred Tank

Abstract

High solidity pitched blade turbines (HSPBT) are widely used in gas-liquid stirred tanks for their effective gas dispersion performance. The blade angle of these impellers is a key design parameter that influences gas dispersion, power consumption, and bubble characteristics. This study investigates the effect of blade angle on gas dispersion performance in HSPBT-equipped stirred tanks using optical probe measurements and computational fluid dynamics (CFD) simulations.

Three blade angles (30°, 45°, and 60°) were examined, with measurements of gas holdup, power consumption, and bubble properties (size, frequency, and velocity) taken at various operating conditions. Increasing the blade angle from 30° to 60° increased both overall gas holdup and power consumption. At the 30° blade angle, bubble frequency was approximately three times higher at the impeller trailing edge compared to the tank centre and wall, with 15–20% lower average bubble velocity at the trailing edge. The HSPBT with a 45° blade angle achieved the highest gas holdup with finer bubbles at a reasonably lower power input compared to the 60° configuration, making it the preferred design for efficient gas-liquid mass transfer in stirred tanks.

@article{prakash2018impact,
  title         = {Impact of HSPBT Blade Angle on Gas Phase Hydrodynamics in a Gas--Liquid Stirred
                  Tank},
  author        = {Prakash, Baranivignesh and Shah, Milinkumar T and Pareek, Vishnu K and Utikar,
                  Ranjeet P},
  year          = 2018,
  journal       = {Chemical Engineering Research and Design},
  publisher     = {Elsevier},
  volume        = 130,
  pages         = {219--229}
}