Gas dispersion impellers, such as the Rushton turbine and the more. recent
concave blade turbines, all feature blades that are symmetric with respect
to the plane of the disc. This despite the fact that the gas usually enters
from the bottom, and thus causes a flow pattern that is distinctly asymmet
ric. This article discusses the performance of a gas dispersion impeller wi
th blades that are vertically asymmetric, i.e. the blade: shape above the d
isk is different from the shape below the disk. It is shown that this impel
ler has a gassed power curve that is flatter than that of other impellers.
Furthermore, it can disperse more gas before flooding than the impellers wi
th symmetric blades.