The KSX four-wide-blade helical impeller is an axial flow impeller. Its bent curved blades give it very low shear force and high turbulent diffusion capacity. Compared with traditional PDY impellers, it can improve the mass transfer coefficient by 20% at the same power consumption and save 30% of electricity consumption at the same mixing intensity. It is especially suitable for mass transfer, solid suspension, and shear-sensitive fermentation oxygenation processes.