Investigation of the Effect of Magnetic Fields on the Volume Index of Diluted Municipal Wastewater Sludge

Abstract

One of the most important problems in the process of wastewater treatment by the complete mix activated sludge method is the production of a large volume of sludge, which poses many problems in the management and conditioning of sludge. Since about 60% of the operating costs of wastewater treatment plants are related to sludge management, so any modified process that can produce less sludge can be effective in reducing costs and better sludge management. The use of magnetic fields to treat wastewater has been considered by researchers in recent years due to the lack of application of chemicals in these processes. This study considered the use of MFs strength in the range of 0.19 to 3.21 mT on diluted sludge volume index for 30 minutes. The rate of reduction of this index in the case samples compared to the control samples from 10 to 100 mL/g was different. During this period, the difference between the temperatures of the case samples compared to the control samples was statistically significant and was estimated from 0.4 to 20 °C. The difference between mean pH of the case and control samples was significant but the dissolved oxygen concentration of them, similar to other variables’ factors that affect the process, was not statistically significant (p> 0.05).

Keywords

• magnetic fields
• diluted sludge volume index
• municipal wastewater