Effect of Rotational Speed of a Self-Aspirating Mixer on Oxygen Saturation in Water

There are two categories of gas-liquid mixers: conventional and special-purpose. In theory, any conventional mixer can be applied to aerate a liquid, but fast-rotating devices are generally preferred. Special-purpose mixers (tubular, prismatic, cylindrical) have a hollow shaft, and operate by drawing gas from above the surface of the liquid and dispersing it inside the liquid. This process is referred to as aspirated aeration. In contrast, conventional mixers increase the pressure of the aspirated gas. Gas drawn from above the surface of the liquid flows through channels bored inside the shaft and the impeller, and is introduced to the liquid in this way. This article presents the results of an experiment investigating the aeration efficiency of a six-tube self-aspirating mixer at different rotational speeds. The experiment was conducted in a flow tank. The results indicate that self-aspirating mixers are effective devices for water aeration and mixing.