DOI: 10.36347/sjet.2019.v07i02.001

Pages: 33-40

Oxygen transfer efficacy highly depends on bubbles’ size, bubbles’ release rate, and bubbles’ velocity while traveling toward the surface of the water. This work presents a mathematical modeling that correlates bubble release rate, bubble size, and bubble velocity to volumetric mass transfer coefficient, 1/hr (KLa). Multiple studies show models that correlate KLa to the concentration of oxygen for different flow patterns but this study focuses on a model that connects KLa to geometrical parameters. The model in this study was built on experimental data for a standard rubber membrane (SS2) manufactured by Xylem’s Sanitaire company and tested with a new membrane, Sharp Nub, which was developed by Amano and Alkhalidi. The model was able to predict the experimental KLa20 values with slight variation. The proposed model can predict the KLa20 based on bubble release rate, bubble velocity, and bubble size. That makes it simpler to investigate the effects of changing any of these parameters without experimentation, thereby saving time and effort. By attaining the KLa20 values for a membrane, standard oxygen transfer efficacy (SOTE) can be easily found making it simpler to compare diffuser performances.