title: Hydrodynamic cavitation as a novel approach for pretreatment of oily wastewater for anaerobic co-digestion with waste activated sludge.
abstract: Application of hydrodynamic cavitation (HC) was investigated with the objective of biogas production enhancement from co-digestion of oily wastewater (OWW) and waste activated sludge (WAS). Initially, the effect of HC on the OWW was evaluated in terms of energy consumption and turbidity increase. Then, several mixtures of OWW (with and without HC pretreatment) and WAS with the same concentration of total volatile solid were prepared as a substrate for co-digestion. Following, several batch co-digestion trials were conducted. To compare the biogas production, a number of digestion trials were also conducted with a mono substrate (OWW or WAS alone). The best operating condition of HC was achieved in the shortest retention time (7.5 min) with the application of 3mm diameter orifice and maximum pump rotational speed. Biogas production from all co-digestion reactors was higher than the WAS mono substrate reactors. Moreover, biogas production had a direct relationship with OWW ratio and no major inhibition was observed in any of the reactors. The biogas production was also enhanced by HC pretreatment and almost all of the reactors with HC pretreatment had higher reaction rates than the reactors without pretreatment.
authors.affiliation: Faculty of Environment, University of Tehran, No. 25, Ghods St., Enghelab Ave., Tehran, Iran; Faculty of Civil and Environmental Engineering, Ostfalia University of Applied Sciences, Herbert-Meyer-Str. 7, 29556 Suderburg, Germany. Electronic address: nimahabashi@ut.ac.ir.
authors.forename: Nima
authors.initials: N
authors.lastname: Habashi
authors.affiliation: Faculty of Environment, University of Tehran, No. 25, Ghods St., Enghelab Ave., Tehran, Iran.
authors.forename: Nasser
authors.initials: N
authors.lastname: Mehrdadi
authors.affiliation: Faculty of Civil and Environmental Engineering, Ostfalia University of Applied Sciences, Herbert-Meyer-Str. 7, 29556 Suderburg, Germany.
authors.forename: Artur
authors.initials: A
authors.lastname: Mennerich
authors.affiliation: Department of Water and Wastewater Engineering, Faculty of Civil, Water and Environmental Engineering, Shahid Beheshti University, East Vafadar Blvd, Tehranpars, Tehran, Iran.
authors.forename: Abolghasem
authors.initials: A
authors.lastname: Alighardashi
authors.affiliation: Faculty of Environment, University of Tehran, No. 25, Ghods St., Enghelab Ave., Tehran, Iran.
authors.forename: Ali
authors.initials: A
authors.lastname: Torabian
mesh_terms: D000693:Anaerobiosis; D005285:Fermentation; D057446:Hydrodynamics; D007700:Kinetics; D012722:Sewage; D062065:Wastewater / Q000737:chemistry*; D018508:Water Purification / Q000379:methods*
chemical_list: D012722:Sewage; D062065:Wastewater
keywords: Anaerobic; Batch reactors; Biogas; Co-digestion; Hydrodynamic cavitation; Oily wastewater