Application of iron and aluminum electrodes for wastewater treatment via electrocoagulation

Abstract

The present study deals with the possibility of using iron and aluminum monopolar electrodes for raw domestic wastewater treatment under different treatment conditions. Wastewater samples were collected from Abu Rawash wastewater treatment plant, Egypt. A mini model was constructed for the treatment process. Experiments were carried out using iron and aluminum electrodes separately and for each type at different distances between electrodes (10 and 15 cm). Different factors were studied to enhance the electrocoagulation treatment process which include sedimentation period (3 and 5 h), different electrocoagulation periods (30 and 60 min), and different electrical voltages (12 and 24 V). Alum was used as a coagulant and the final effluent was disinfected with chlorine. The results showed that iron electrodes were more effective than aluminum electrodes for treatment and the distances between electrodes have played a role in the treatment process since 10 cm was more effective than 15 cm. Iron electrodes with 10 cm distance between electrodes showed the maximum removal percent of physicochemical parameters such as TSS (94.2%), COD (90.1%), TKN (89.3%), BOD (95.1%) and total phosphorus (83.3%). Alum enhanced the treatment efficiency and the final chlorinated effluent was in comparable with the local laws for reuse purposes.