Graphical abstract Highlights • The PBR-UF was used for algal cultivation, harvest, and ADE purification. • Bacteria-algae symbiosis enhanced removals of organics and nutrients in PBRs. • Immobilized algal beads avoided cells lysis in the UF filtration. • Cake layer in ICV + PAC served a filter layer to alleviate membrane fouling. • The EEM-PARAFAC approach was used for fluorescent organics degradation analysis. Abstract A photobioreactor (PBR) coupled with ultrafiltration (UF) system was developed with goals of microalgae cultivation, harvest, and membrane fouling control in the anaerobic digestion effluent purification. Firstly, three-sequencing batch PBRs were started-up with suspended Chlorella vulgaris (C. vulgaris , SCV), immobilized C. vulgaris (ICV) and immobilized C. vulgaris with powdered activated carbon (ICV + PAC). The results exhibited high DOC degradation (66.61%–84.35%) and completely nutrients (nitrogen and phosphorus) removals were attained in PBRs. This indicated bacterial-microalgal consortiums enhanced biodegradation and PAC adsorption accelerated photodegradation. During the microalgae harvest by UF, immobilized microalgae beads protected cells integrity with less debris and intracellular/extracellular organic matters lysis. Moreover, the cake layer in ICV + PAC could even serve as a dynamic layer to entrap the residual pollutants and control membrane fouling. Hence, membrane fouling mitigation and ADE purification were realized during the microalgae harvest process in the ICV + PAC. [ABSTRACT FROM AUTHOR]