عنوان مقاله [English]
Access to safe drinking water is an important means of safeguarding public health. This cross-sectional study was designed to investigate the performance of electrocoagulation in the treatment of surface waters. For this purpose, water samples were taken from the intake to the Soleymanshah-Songhor Dam. Treatment was carried out in a reactor operating in the batch mode. Experiment runs were designed using the Design Expert Software (Stat-Ease Inc., Version 6.0.6) to investigate the effects of voltage (5-25), reaction time (20-60), temperature (10-30Ċ), and rapid mixing (200-400) on the Mn (II), Fe (II), hardness, alkalinity, and turbidity removal efficiencies as a result of treatment with aluminum electrodes. After the treatment process, the study parameters and the dissolved metal content due to the dissolution of the anode electrode were measured. Maximum removal efficiencies for Fe (II), Mn (II), hardness, and alkalinity were 96.2%, 94.6%, 26.6%, and 12.2%, respectively, while turbidity reduced from 0.6 to 0.15 NTU. Moreover, the dissolved Al content in the treated sample was found to be higher than the standard limit allowed for drinking water. Thus, the electrocoagulation process seems to be effective in the removal of the investigated contaminants from surface waters. However, the factor limiting the use of this method under maximum efficiency conditions is the dissolved metal content due to the dissolution of the anode electrode, which is a significant concern for the public health. In contrast, the electrocoagulation process seems to be an efficient and safe pretreatment method using aluminum electrodes if operated for achieving optimum efficiencies.
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