Journal of Water and Wastewater; Ab va Fazilab (in persian)

Journal of Water and Wastewater; Ab va Fazilab (in persian)

Oil Wastewater Treatment by Electrocoagulation Process Using Scrap Aluminum as Electrodes: Optimization and Economic Evaluation

Document Type : Research Paper

Authors
Nima Bolivand 1
Mohammad Delnavaz 2
1 MSc. Student in Civil and Environmental Engineering, Dept. of Civil Engineering, Faculty of Engineering, Kharazmi University,Tehran, Iran
2 Assoc. Prof., Dept. of Civil Engineering, Faculty of Engineering, Kharazmi University, Tehran, Iran
10.22093/wwj.2026.560644.3532
Abstract
The aim of this study is to evaluate the economics and optimize the electrocoagulation process for the treatment of a real wastewater sample from oil refining with an initial COD of 406 mg/L using scrap aluminum as perforated electrodes (anode and cathode) and solar energy received by the solar panel to provide the electricity required for the process. Electrolysis time (0 to 60 min), current density (6.98 to 34.9 A/m2), and electrode spacing (1 to 5 cm) were investigated using the response surface methodology, while central square design was used to determine the optimal experimental conditions. The experimental results indicate the significance of slectrode spacing, in addition to current density, which is directly dependent on the number and size of holes created on the electrode. Economic evaluations indicate the possibility of using scrap aluminum as a replacement for regular aluminum, which led to savings in operating costs. Finally, the optimal conditions for conducting experiments were obtained with an electrolysis time of 48 min, a current density of 92.27 A/m2, and an electrode distance of 2 cm. Under these conditions, the COD and TDS removal percentages were 70 and 15.3%, respectively, which is relatively in line with the predictions of the designed model (68.7 and 15.1 percent, respectively). According to the calculations made in this study, and considering the costs required to provide solar energy with the current energy price in Iran (Tehran), the use of solar energy to provide the energy needed for the electrocoagulation process on a small scale is not recommended. One of the main reasons for the inefficiency of solar energy use on a smaller scale is the low cost of industrial electricity in the country.
Keywords
Electrochemical Treatment
Electrocoagulation
Petroleum Wastewater
Solar Energy
Scrap Metal
Perforated Electrode
Subjects
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Journal of Water and Wastewater; Ab va Fazilab (in persian)
Volume 36, Issue 4 - Serial Number 159
November and December 2025
Pages 1-17