Influence of microalgae retention time on biomass production in membrane photobioreactor using human urine as substrate

Abstract

Human urine is known as the excreta with a high concentration of nitrogen and phosphorus, causing eutrophication in water bodies. In this study, human urine was used to feed microalgae (Chlorella vulgaris) in a membrane photobioreactor (MPBR) at various microalgae retention times (MRTs) and hydraulic retention time (HRT) of 2 days to evaluate its biomass production. The results indicate that MPBR was operated under MRT of 2 to 5 days and HRT of 2 days, which performed the optimum condition with biomass productivity from 146.43±8.52 to 151.93±15.05 mg.l^-1.day. Moreover, the MPBR using the urine as a nutrient source demonstrated the high performance in biomass production and strong growth of microalgae.