A novel flat plate algal bioreactor with horizontal baffles: Structural optimization and cultivation performance

A novel flat plate photobioreactor with horizontal baffles was developed. The effects of aeration intensity and aeration site were investigated using computational fluid dynamics. The effects of baffle structural parameters, including the ratio of clearance between the baffle and the bioreactor wall (d) to bioreactor width (D) and the ratio of distance between two adjacent baffles (h) to D on the flow and mixing performance were assessed. A good light/dark cycle and strong, uniform mixing performance were created at d/D = 0.5 and h/D = 1 when the aeration site was located at the bottom center. The cultivation performance was assessed by culturing Chlorella vulgaris 31. The maximum biomass productivity in the optimized bioreactor was 1.88 times than that of a traditional bioreactor without baffles. For a light path length of 80 mm, the optimized baffles offer a large economical advantage in improving algal productivity and reduce growth condition difference.