Generation of microbubbles through single loop and double loop fluid oscillator for photobioreactor aeration

Abstract

Microbubbles are known for their many applications. Recently there has been new findings regarding the growth of susceptible microalgae through microbubble aeration. There are three methods used to generate microbubbles for this microalgae strain. Unfortunately, for some methods, the cost of generating microbubbles is still high. However, fluidic oscillators can be used to produce microbubbles at a reasonable cost. There are two types of fluid oscillators: single loop and double loop. This study determined the bubble size produced with these oscillators. Bubble size data was recorded using a high-speed camera at air flow rates of 6 LPM, 9 LPM, 12 LPM, and 15 LPM, and utilized 10 μm microporous shafts as the diffuser. The data were processed using ImageJ software. The results showed that the size of the bubble using a single loop fluid oscillator was smaller than that of the double loop fluid oscillator. The smallest bubble size was obtained in a single loop fluid oscillator with an airflow of 6 LPM.