Optimization of Activated Sludge Physical Properties by Magnetic Field via Response Surface Modeling

Abstract:

In this study, activated sludge was exposed by magnetic field exhibited from NdFeB – type of permanent magnets. The exposure was aimed to improve the physical properties of the activated sludge used in treating wastewater. Hence, it was hypothesized that the magnetically-exposed activated sludge is potential in enhancing the efficiency of removal performances of the wastewater treatment processes. The influence of magnetic field, exposure time, biomass concentration and mixing intensity on turbidity reduction, aggregation and settling velocity was thoroughly investigated. Response surface methodology (RSM) was applied for experimental design, analysis and optimization. Based on the results, magnetically-exposed activated sludge displayed certain trends showing that its properties were positively affected by magnetic field. At the optimum conditions of magnetic field of 88.0 mT, exposure time of 38.5 hrs, biomass concentration of 3380 mg/L and mixing intensity of 345 rpm achieved 68.3%, 60.1% and 0.0104 cm/s of turbidity reduction, aggregation and settling velocity, respectively.

• Periodical: Applied Mechanics and Materials (Volume 567)
• Pages: 98-103
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.567.98
• Online since: June 2014
• Authors: Zaidi Nur Syamimi, Khalida Muda, Johan Sohaili, Mika Sillanpää
• Keywords: Activated Sludge, Magnetic Field, Physical Properties, RSM, Wastewater Treatment

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