Using fluorescent material for enhancing microalgae growth rate in photobioreactors

This study investigates the spectral shifting UV-A radiation by fluorescent material as a tool for enhancing Chlorella sp. growth rate in photobioreactors made of UV-stabilized polycarbonate (PC). The fluorescent dye was dissolved in a thermoplastic acrylic resin, and the mixture was applied as a coating on to the substrates. The feasibility of using the fluorescent coating as wavelength shifter layer to shift UV-A radiation of a full spectrum light source to the photosynthetically active region (PAR) was explored. For this purpose, a solution of the fluorescent dye in resin was prepared and used to coat front surface of the reactor. Comparing to the uncoated reactor, the reactor coated with the wavelength shifter layer exhibited about 10 % increase in biomass productivity over the same culture period. It was also found that the elimination of UV-A radiation increases chlorophyll a content in the cells.