Comparative performance of UASB and anaerobic hybrid reactors for the treatment of complex phenolic wastewater

► Performance of AHR and UASB reactor was compared for the removal of phenolics. ► Fast start-up and granulation of biomass was noted in AHR. ► Lowering HRT led to decline in phenolics removal in AHR(99-77%) and UASB(95-68%). ► AHR could withstand higher shock load compared to UASB reactor. ► 12,159 MJ d−1 more energy can be generated using AHR.