Ultrasound enhancement of near-neutral photo-Fenton for effective E. coli inactivation in wastewater.
In this study, we attempt for the first time to couple sonication and photo-Fenton for bacterial inactivation of secondary treated effluent. Synthetic wastewater was subjected to sequential high-frequency/low power sonication, followed by mild photo-Fenton treatment, under a solar simulator. It was followed by the assessment of the contribution of each component of the process (Fenton, US, hv) towards the removal rate and the long-term survival; sunlight greatly improved the treatment efficiency, with the coupled process being the only one to yield total inactivation within the 4-h period of treatment. The short-term beneficial disinfecting action of US and its detrimental effect on bacterial survival in long term, as well as the impact of light addition were also revealed. Finally, an investigation on the operational parameters of the process was performed, to investigate possible improvement and/or limitations of the coupled treatment; 3 levels of each parameter involved (hydraulic, environmental, US and Fenton) were tested. Only H2O2 increased improved the process significantly, but the action mode of the joint process indicated potential cost-effective solutions towards the implementation of this method.
Laboratory of Environmental Engineering and Planning, Department of Civil Engineering, Aristotle University of Thessaloniki, 54624 Thessaloniki, Greece; Laboratory of Control of Environmental Contamination, Institute of Textile Research and Industrial Cooperation of Terrassa (INTEXTER), Universitat Politècnica de Catalunya, Colom 15, 08222 Terrassa, Catalonia, Spain; Swiss Federal Institute of Technology, Lausanne, Institute of Chemical Sciences and Engineering, 1015 Lausanne, Switzerland.
Stefanos
S
Giannakis
Swiss Federal Institute of Technology, Lausanne, Institute of Chemical Sciences and Engineering, 1015 Lausanne, Switzerland.
Stefanos
S
Papoutsakis
Laboratory of Environmental Engineering and Planning, Department of Civil Engineering, Aristotle University of Thessaloniki, 54624 Thessaloniki, Greece.
Efthymios
E
Darakas
Laboratory of Control of Environmental Contamination, Institute of Textile Research and Industrial Cooperation of Terrassa (INTEXTER), Universitat Politècnica de Catalunya, Colom 15, 08222 Terrassa, Catalonia, Spain; Department of Chemical Engineering & Terrassa School of Engineering, Universitat Politècnica de Catalunya, Colom 1, 08222 Terrassa, Catalonia, Spain.
Antoni
A
Escalas-Cañellas
Laboratoire Rhéologie et Procédés, Grenoble-INP, UMR CNRS 5520, BP 53, 38041 Grenoble Cedex 9, France; King AbdulAziz University, Jeddah, Saudi Arabia.
Christian
C
Pétrier
Swiss Federal Institute of Technology, Lausanne, Institute of Chemical Sciences and Engineering, 1015 Lausanne, Switzerland. Electronic address: cesar.pulgarin@epfl.ch.
César
C
Pulgarin
D004203:Disinfection; D004926:Escherichia coli / Q000187:drug effects / Q000502:physiology* / Q000528:radiation effects; D006861:Hydrogen Peroxide / Q000494:pharmacology*; D007501:Iron / Q000494:pharmacology*; D008027:Light; D050296:Microbial Viability / Q000187:drug effects* / Q000528:radiation effects*; D013010:Sonication; D013696:Temperature; D013997:Time Factors; D062065:Wastewater / Q000382:microbiology*; D018508:Water Purification
D006861:Hydrogen Peroxide; D007501:Iron; D062065:Wastewater; C045076:Fenton's reagent
E. coli; High-frequency ultrasound; Inactivation mechanism; Photo-Fenton; Wastewater disinfection