摘要

BACKGROUND: Hydrocarbons are attractive substrates for bioconversion to an expansive range of commodity products. Since these are aerobic bioprocesses, an overall volumetric oxygen transfer coefficient (K(L)a) which facilitates sufficient oxygen transfer is critical to their optimum operation, design and scale-up. RESULTS: The significant parameters influencing K(L)a, the oxygen transfer area and the oxygen transfer coefficient (K-L) were identified in simulated model hydrocarbon-based bioprocesses comprising alkane-aqueous dispersions with suspended yeast using a rigorous statistical approach. K-L a was measured using the dynamic procedure incorporating the probe constant. Transfer area was determined using photography and image analysis. Concurrent determination and correlation of K(L)a, K-L and transfer area, under regimes defined by agitation rate and yeast and alkane concentration, facilitated quantification of the dominant causative factor underpinning K-L a behaviour as the Sauter mean diameter or K-L, depending on the operational regime. Potential mechanisms which corroborate these results have been discussed. CONCLUSION: The systematic identification, quantification and correlation of the parameters and mechanisms impacting on K(L)a in hydrocarbon-based bioprocesses, and the comprehensive and statistically validated empirical data, provide an expedient platform to support future development of a fundamental model for the prediction of K(L)a in these systems.

  • 出版日期2016-10