:: Volume 15, Issue 2 (summer 2017) ::
jmj 2017, 15(2): 32-46 Back to browse issues page
Investigation of Electrocoagulation/Electroflotation Process Efficiency with Aluminum-Graphite felt Electrodes in Removal of E.coli and S. typhimurium from Drinking Water
Soudabeh Alizadeh , Ahmad Mokhrari , Fariba Jedi , Fatameh Ataei , Tayyebeh Sadeghi , Esrafil Asgari , Sahram Nazari
Abstract:   (1535 Views)
Background: Water disinfection by electrochemical methods has been increasingly carried out recently. The aim of this applied research is to investigate the removal of E. coli and S. typhimurium bacteria from drinking water by using Electrocoagulation (EC) - Electroflotation (EF) with Aluminum- Graphite felt electrodes parallel with the monopole mode.
Methods: An experimental study was conducted in a batch system. In this study, the contaminated water samples were prepared through adding of E. coli and S. typhimurium bacteria with concentrations of 104, 105 and 106 CFU/ml. Independent variables Included: different concentrations of E.coli and S. typhimurium bacteria (104, 105 and 106 CFU/mL), reaction time (5, 10, 15 and 20 min), initial pH (7, 8 and 9), electrode gap (1, 2 and 3 cm), current density (0.83, 1.67 and 2.5 mA/cm2) to determine the optimum conditions were investigated.
Results: The results show that in the optimum conditions with increasing the pH from 7 to 9 removal efficiency of bacterial strains of E.coli and S. typhimurium were decreased significantly from 100 to 83% and 100 to 90%, respectively. In initial concentration of 105 CFU/mL, optimum conditions were obtained for current density, reaction time and electrodes gap; 2.5 mA/cm2, 20 min and 2 cm, respectively. With increasing current density and reaction time in both strains of bacteria, were decreased significantly. The electrodes gap do not have much impact on the efficiency of the process. The amount of electrical energy consumed in optimal conditions was calculated 1/8172 KWh/m3.
Keywords: Electrocoagulation, Electroflotation, E. coli, S. typhimurium, Drinking Water, Disinfection
Full-Text [PDF 383 kb]   (789 Downloads)    
Type of Study: Research | Subject: Microbshensi
Received: 2017/07/28 | Accepted: 2017/11/7 | Published: 2017/11/11

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Volume 15, Issue 2 (summer 2017) Back to browse issues page