In this study, the effects of photoperiod on PSB biomass and pigments production in PSB wastewater treatment were examined.
Results showed that the PSB biomass and carotenoid and bacteriochlorophyll were greatly affected by the light/dark cycle and the light/dark cycle frequency. With light/dark cycle of 2h/1h and frequency of 8∼48 times per day, COD removal, the biomass and biomass yield, and light energy efficiency were the highest. On the other hand, the pigments contents were higher at a low light/dark frequency of 2∼4 times per day.