Algae Removal by Electro-coagulation Process, Application for Treatment of the Effluent from an Industrial Wastewater Treatment Plant

Abstract

Background: Although stabilization ponds and lagoons are suitable treatment processes due to simplicity of operation and low per capital costs, the effluents of these systems have too high of a total suspended solids concentration to be discharged into receiving waters. This problem is mainly caused by algae. In this study, an electro-coagulation reactor was examined to re­move algae from the final effluent of the wastewater treatment plant belong to Bu-Ali Industrial Estates (Hamadan City).

 Methods: For the continuous flow electro-coagulation reactor used in these experiments three aluminum anodes were util­ized. This type of metal was selected because it could introduce the flocculation agent into the effluent, thereby algae could be removed by both mechanisms of electro-flotation and electro-flocculation.

Results: The results of treatment were remarkably good and the efficiencies of total suspended solids (TSS) and chlorophyll a removal reached to as high as 99.5% and about 100% by applying a power input of about 550 W. In fact, this level of power input was needed for complete removal of algae in a low retention time of 15 minutes. Meanwhile, by applying less power input of about 100Wdm^-3, the required time for a relatively same treatment was reached to 30 minutes.

Conclusion: It is expected that this method which is also known as a multiple contaminants removal process will be consid­ered as a suitable alternative for final polishing of effluents from lagoons and similar treatment systems.