Electrocoagulation Process for Treatment of Detergent and Phosphate

Background & Aims of the Study: Detergent and phosphate are one of the main and vital threats (eutrophication phenomenon and production of synthetic foam) for the source of drinking water, agriculture and industrial uses in the Ahvaz, Iran that threaten human health. The aim of this study is the evaluation of the efficiency of the electrocoagulation (EC) process in the removal of detergent and phosphate from car wash effluent. Materials & Methods: In this experimental study, we used a glass tank with a volume of 2-4 liters (effective volume of 2 liters) containing 4 electrode-plate iron and aluminum (AL-AL, AL-Fe, Fe-Fe). Bipolar method was used to convert alternative electricity to direct; electrodes were connected to a power supply. Daily samples were collected from different car washes sewage. Initial PHs of samples was from 7 to 9. At first, different tests were performed on primary samples. Reaction times were set for 90, 60 and 30 minutes with middle intervals of 2 cm. Results: According to the result of this study, percentage of phosphate removal in the EC with Al-Fe electrode, with an optimum pH = 7, has been from 34 % (in the 10 Volt) to 78% (in the 30 Volt). Percentage of detergent removal in the EC with AL electrode, with an optimum pH = 7, has been from 68 % (in the 10 Volt) to 94% (in the 30 Volt). Conclusions: Altogether, it was found that this method can be used as a confident and convenient method for treating car wash effluent and according to the highest removal efficiency of the process, effluent can be discharged safely into the environment.