Experimental investigation of a local recirculation photobioreactor for mass cultures of photosynthetic microorganisms.
The present work deals with the experimental fluid mechanics analysis of a wavy-bottomed cascade photobioreactor, to characterize the extent and period of recirculatory and straight-flowing streams establishing therein as a function of reactor inclination and liquid flow rate. The substream characterization via Feature Tracking (FT) showed that a local recirculation zone establishes in each vane only at inclinations ≤6° and that its location changes from the lower (≤3°) to the upper part of each vane (6°). A straight-flowing stream flows opposite (above or below) the local recirculation stream. The recirculation time ranges from 0.86 s to 0.23 s, corresponding, respectively, to the minimum flow rate at the minimum inclination and to the maximum flow rate at the maximum inclination where recirculation was observed. The increase of photosynthetic activity, resulting from the entailed "flash effect", was estimated to range between 102 and 113% with respect to equivalent tubular and bubble column photobioreactors.
Dipartimento di Ingegneria Civile Edile e Ambientale, Sapienza Università di Roma, via Eudossiana 18, 00184 Roma, Italy. Electronic address: monica.moroni@uniroma1.it.
Monica
M
Moroni
Dipartimento di Ingegneria Chimica Materiali Ambiente, Sapienza Università di Roma, via Eudossiana 18, 00184 Roma, Italy. Electronic address: agnese.cicci@uniroma1.it.
Agnese
A
Cicci
Dipartimento di Ingegneria Chimica Materiali Ambiente, Sapienza Università di Roma, via Eudossiana 18, 00184 Roma, Italy. Electronic address: marco.bravi@uniroma1.it.
Marco
M
Bravi
D001709:Biotechnology / Q000295:instrumentation* / Q000379:methods; D004867:Equipment Design; D007091:Image Processing, Computer-Assisted; D058086:Microalgae / Q000502:physiology*; D058433:Photobioreactors; D010788:Photosynthesis
Fluid mechanics; Microalgae; Particle tracking; Photobioreactor; Recirculation