A hetero-photoautotrophic two-stage cultivation process to improve wastewater nutrient removal and enhance algal lipid accumulation

► Effective coupling municipal wastewater treatment with algae-based biofuel production. ► Development of a hetero-photoautotrophic two-stage cultivation process. ► The maximal algal biomass concentration reached above 1.1 g/L with lipid content around 30%. ► High wastewater nutrient removal efficiencies for phosphorus, ammonia, total nitrogen and COD. ► The two-stage model developed can be used to treat organic-rich wastewaters.