Removal of COD from laundry wastewater by electrocoagulation/electroflotation.
Chih-Ta Wang1, Wei-Lung Chou, Yi-Ming Kuo
1Department of Safety Health and Environmental Engineering, Chung Hwa University of Medical Technology, Tainan County, Hsien 717, Taiwan. ctwwang@mail.hwai.edu.tw
Journal of Hazardous Materials
|September 5, 2008
Summary
Electrocoagulation/electroflotation effectively removes chemical oxygen demand (COD) from laundry wastewater. Ultrasound application and aluminum electrodes significantly enhance COD removal efficiency, achieving up to 62%.
Area of Science:
- Environmental Science
- Water Treatment Technologies
- Electrochemistry
Background:
- Laundry wastewater contains significant chemical oxygen demand (COD) requiring efficient treatment.
- Electrocoagulation/electroflotation (EC/EF) is a promising technology for wastewater remediation.
- Optimizing EC/EF parameters is crucial for effective COD removal.
Purpose of the Study:
- To evaluate the COD removal efficiency of simulated laundry wastewater using EC/EF.
- To investigate the impact of ultrasound, electrode material, voltage, and chloride concentration on COD removal.
- To determine optimal operating conditions for energy-efficient COD removal.
Main Methods:
- Simulated laundry wastewater was treated using electrocoagulation/electroflotation.
- Experiments were conducted with varying parameters: ultrasound application, electrode materials (Al, Fe), electrode connection (monopolar, bipolar), applied voltage, and chloride concentration.
- COD removal efficiency and energy consumption were measured.
Main Results:
- Ultrasound application improved COD removal efficiency to approximately 62%.
- Optimal COD removal was achieved at an applied voltage of 5V, balancing efficiency and energy consumption.
- Aluminum electrodes outperformed iron electrodes, and monopolar connection was more effective than bipolar.
- Chloride concentration below 2500ppm positively influenced removal efficiency.
Conclusions:
- EC/EF, particularly with ultrasound and aluminum electrodes, is highly effective for laundry wastewater COD removal.
- Optimized voltage and monopolar configuration enhance treatment performance and energy efficiency.
- The study provides valuable insights for designing efficient electrocoagulation systems for industrial wastewater treatment.
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