Question

What results in impeller flooding?

(a) Increase impeller speed

(b) Increases gas velocity

(c) Decrease impeller speed

(d) Decrease gas velocity

I have been asked this question in class test.

This intriguing question comes from Aeration and Agitation topic in chapter Aeration and Agitation of Fermentation Technology

Answer 1

Correct option is (b) Increases gas velocity

Explanation: If the gas flow rate is very high, it would not allow oxygen to be dissolved in the medium and the gas may exit without dissolving. Therefore, most of the gas remains unutilized and this results in impeller flooding.