Evaluation of COD and Turbidity Removal Efficiency Using Hybrid Electrocoagulation-Electrooxidation–Based Domestic Wastewater Treatment
摘要
The detection of high chemical oxygen demand (COD), biochemical oxygen demand (BOD), and turbidity in domestic sewage effluent results in considerable ecological harm in terms of the significant organic load and contamination. According to the literature, only a few studies have been conducted on treating sewage water by combining any two electrochemical processes. Thus, this study assesses the effectiveness of a hybrid method combining electrocoagulation and electrooxidation for domestic wastewater treatment. In the electrocoagulation process, the efficacy of iron electrodes was assessed over a wide range of pH (4–10), current intensities (1–2.5 A), and electrolysis times (10–30 min), with optimal conditions (20 min, 2.5 A, pH 10) yielding maximum removal efficiencies of 90% for COD, 98.7% for turbidity, 89.5% for BOD, 85.6% for nitrate (NO3−), and 65.2% for total organic carbon (TOC). In the subsequent phases of the investigation, the effluent resulting from the electrocoagulation process was subjected to electrooxidation, designating the process as hybrid electrocoagulation-electrooxidation. The hybrid electrocoagulation-electrooxidation investigations were conducted utilizing graphite electrodes. Under optimal conditions (electrolysis duration 70 min, current 2.5 A, initial pH 10), the removal efficiencies for COD, turbidity, BOD, and TOC reached 96%, 99.2%, 95.1%, and 74.3%, respectively. This investigation establishes the efficacy of the hybrid electrocoagulation-electrooxidation approach over the electrocoagulation process in isolation for the effective removal of high COD, turbidity, and other pollutants from domestic wastewater. This study also examines the economic evaluations and sludge characterization of EC and hybrid EC-EO processes, in contrast to existing literature that predominantly focuses on performance metrics.