Simultaneous production of 3-biofuels (hydrogen, ethanol and methane) as by-products of the biodegradation of petrochemical wastewater containing MEG via anaerobic packed bed baffled reactor (AnPBBR), was extensively investigated. A four-chambered reactor supported by polyurethane sheets, was operated at a constant hydraulic retention time (HRT) of 36 h and different organic loading rates (OLRs) of 0.67, 1, 2 and 4 gCOD/L/d. The maximum specific H-2 and CH4 production rates of 438.07 +/- 43.02 and 237.80 +/- 21.67 ml/L/d were respectively achieved at OLR of 4 gCOD/L/d. The residual bio-ethanol significantly increased from 57.15 +/- 2.31 to 240.19 +/- 34.69 mg/L at increasing the OLR from 0.67 to 4 gCOD/L/d, respectively. The maximum MEG biodegradability of 98% was attained at the lowest OLR Compartment wise profiles revealed that the maximum H-2 and ethanol production were achieved at HRT of 9 h (1st compartment), while the CH4 production was peaked at HRTs of 27 and 36 h (last two compartments). Kinetic studies using Stover-Kincannon and completely stirred tank reactor (CSTR) in series models were successfully applied to the AnPBBR overall and compartment-to-compartment performance, respectively. The economic evaluation strongly revealed the potentials of using AnPBBR for simultaneous treatment and bio-energy production from petrochemical wastewater as compared to the classical anaerobic baffled reactor (ABR). Microbial analysis using Illumina MiSeq sequencing showed a diversity of bacterial community in AnPBBR. Proteobacteria (36.62%), Firmicutes (20.85%) and Bacteroidetes (3.44%) were the most dominant phyla. (C) 2016 Elsevier Ltd. All rights reserved.