title: Simultaneous Hydrogen and Methane Production Through Multi-Phase Anaerobic Digestion of Paperboard Mill Wastewater Under Different Operating Conditions.
abstract: Multi-phase anaerobic reactor for H2and CH4production from paperboard mill wastewater was studied. The reactor was operated at hydraulic retention times (HRTs) of 12, 18, 24, and 36 h, and organic loading rates (OLRs) of 2.2, 1.5, 1.1, and 0.75 kg chemical oxygen demand (COD)/m3day, respectively. HRT of 12 h and OLR of 2.2 kg COD/m3day provided maximum hydrogen yield of 42.76 ± 14.5 ml/g CODremovedand volumetric substrate uptake rate (-rS) of 16.51 ± 4.43 mg COD/L h. This corresponded to the highest soluble COD/total COD (SCOD/TCOD) ratio of 56.25 ± 3.3 % and the maximum volatile fatty acid (VFA) yield (YVFA) of 0.21 ± 0.03 g VFA/g COD, confirming that H2was mainly produced through SCOD conversion. The highest methane yield (18.78 ± 3.8 ml/g CODremoved) and -rS of 21.74 ± 1.34 mgCOD/L h were achieved at an HRT of 36 h and OLR of 0.75 kg COD/m3day. The maximum hydrogen production rate (HPR) and methane production rate (MPR) were achieved at carbon to nitrogen (C/N) ratio of 47.9 and 14.3, respectively. This implies the important effect of C/N ratio on the distinction between the dominant microorganism bioactivities responsible for H2and CH4production.
authors: Environmental Engineering Department, Egypt-Japan University of Science and Technology (E-JUST), P.O. Box 179, New Borg El Arab City, 21934, Alexandria, Egypt. Ahmed.abdelwahhab@ejust.edu.eg.
authors: Ahmed
authors: http://orcid.org/0000-0002-8014-3006
authors: A
authors: Farghaly
authors: Environmental Engineering Department, Egypt-Japan University of Science and Technology (E-JUST), P.O. Box 179, New Borg El Arab City, 21934, Alexandria, Egypt.
authors: Ahmed
authors: A
authors: Tawfik
mesh_terms: D000693:Anaerobiosis; D001419:Bacteria / Q000737:chemistry / Q000378:metabolism*; D019149:Bioreactors; D006859:Hydrogen / Q000737:chemistry*; D007220:Industrial Waste; D008697:Methane / Q000096:biosynthesis / Q000737:chemistry*; D009584:Nitrogen / Q000737:chemistry; D014865:Waste Disposal, Fluid; D062065:Wastewater / Q000737:chemistry
chemical_list: D006859:Hydrogen; D007220:Industrial Waste; D008697:Methane; D009584:Nitrogen; D062065:Wastewater
keywords: Anaerobic baffled reactor; Heating energy consumption; Hydrogen; Methane; Operating conditions; Paperboard mill wastewater