Enhancement of microalgae production by embedding hollow light guides to a flat-plate photobioreactor. (May 2016) - Sun, Yahui
Graphical abstract: Highlights: Hollow PMMA tubes were embedded into a flat-plate photobioreactor as light guides. Average light intensity of interior regions was enhanced 2–6.5 times. The optimized light distribution induced a photosynthetic efficiency of 12.52%. Hollow PMMA tubes aroused additional mixing of the microalgae suspension. Biomass production in photobioreactor with light guides was increased by 23.42%. Abstract: To offset the adverse effects of light attenuation on microalgae growth, hollow polymethyl methacrylate (PMMA) tubes were embedded into a flat-plate photobioreactor (PBR) as light guides. In this way, a fraction of incident light could be transmitted and emitted to the interior of the PBR, providing a secondary light source for cells in light-deficient regions. The average light intensity of interior regions 3–6 cm from surfaces with 70 μmol m −2 s −1 incident light was enhanced 2–6.5 times after 3.5 days cultivation, resulting in a 23.42% increase in biomass production to that cultivated in PBR without PMMA tubes. The photosynthetic efficiency of microalgae in the proposed PBR was increased to 12.52%. Moreover, the installation of hollow PMMA tubes induced turbulent flow in the microalgae suspension, promoting microalgae suspension mixing. However, the enhanced biomass production was mainly attributed to the optimized light distribution in the PBR.