Effect of Magnetic Fields on the Sludge Properties in the Aeration Basin of the Activated Sludge Treatment Process

Purpose: Sludge management is one of the most important problems in wastewater treatment plants (WWTPs) and an activated sludge treatment process. Excessive growth of filamentous bacteria may cause, less dense floc structure, poor sludge compaction, slow settling, and wash-out solids from the final clarifiers. Sludge volume index (SVI) is an unknown method and the most appropriate parameter to express and estimate the settling characteristics of the sludge. The use of chemical materials to increase the volume of sludge is custom, but these methods are expensive and are not a green process. In recent years, the use of integrated treatment methods such as the use of magnetic fields (MFs) with biological methods, to accelerate the growth of microorganisms has become common. Methods: In this case and control study use of MFs (from 0.19 to 3.21mT) to decrease SVI (30 minutes time to settling) or enhancement of sludge, considered. Results: Based on the result of this study by increased the intensity of MFs, a decrease in SVI (0.03 to 53 percent) happened statistically. Conclusion: One of the main, physical, and practical methods to reduce the huge volume of sludge by decrease SVI in WWTPs can be used by applying MFs.