A novel photobioreactor with transparent rectangular chambers for cultivation of microalgae

An open tank photobioreactor containing transparent rectangular chambers (TRCs) was developed to improve the photosynthetic efficiency of microalgal cultivation. The TRCs, made of transparent acrylic, conducted light deep into the photobioreactor, especially at high cell concentrations. The average irradiance, Iav, was calculated by Lambert–Beer's law, and was used to determine the light conditions in the cultivation system. The photobioreactor provided large areas of illumination that improved the effective utilization of light energy for microalgae growth and created a good artificial environment for a high rate of cell growth, even at low Iav. The biomass concentration of Chlorella sp. reached 3.745 g L−1 on the 13th day, with biomass productivity of 0.340 g L−1 d−1. The total biomass obtained was 56% more than that of similar culture systems without TRCs.