Recommended turbulent energy dissipation rate for biomass and lipid production of Scenedesmus obliquus in an aerated photosynthetic culture system

Abstract

Effects of turbulent energy dissipation rate (increased from 1.28 × 10 −6 to 1.67 × 10 −5 m 2 s −3) on Scenedesmus obliquus biomass and lipid accumulation at different aeration rates (0.3, 0.6, 0.9, 1.2, and 1.5 L min −1) were investigated. The turbulent energy dissipation rate was calculated by CFD model simulation. When the turbulent energy dissipation rate increased to 7.30 × 10 −6 m 2 s −3 , the biomass and lipid productivity increased gradually, and finally reached their maximum values of 1.11 × 10 7 cells mL −1 and 16.0 mg L −1 day −1 , respectively. When it exceeded 7.30 × 10 −6 m 2 s −3 , the biomass and lipid productivity showed a decreasing trend. Therefore, the most favorable turbulent energy dissipation rate for S. obliquus growth and lipid accumulation was 7.30 × 10 −6 m 2 s −3 .

Flow Patterns of Multiple Axial‐Radial Impellers for Potential Use in Aerated Stirred Tanks

“…On the other hand, high TI leads to high energy dissipation, which can be linked to high strain rates resulting in fragmentation of and damage to cells. Therefore, the TI is of utmost importance for the mixing of biological media [38][39][40]. The TI is mainly a function of the rotational speed and the impeller geometry.…”