Hydrophysics

Hydrophysics

Investigation to determine the effects of magnetic field on the removal efficiency of COD within an Orbal reactor

Document Type : Original Article

Authors
Hooman Ghahremanzadeh 1
Sara Allahyaribeik 2
Amirhossein Javid 1
Amir hessam Hassani 1
1 Department of Environmental Engineering, Faculty of natural Resources and Environment, Science and Research Branch, Islamic Azad University, Tehran, Iran
2 Department of industry and energy, Faculty of natural Resources and Environment, Science and Research Branch, Islamic Azad University, Tehran, Iran
Abstract
Taking into account the evergrowing human demands for refining and recycling water, issues related to it including wastewater, wastewater treatment and wastewater reuse are important points of consideration. Using of an Orbal reactor for COD removal by activated sludge is considered suitable and efficient by numerous studies in the literature. Moreover, to improve removal efficiencies, it is significant to discover the required tools and methods to decrease over sludge creation. This study aims to investigate the performance of COD removal by combining a magnetic field within an oxidation ditch Orbal reactor. First the study was piloted in a laboratory context to test the impact of the application of the magnetic field in ideal conditions. Then, two magnetic fields of different strengths, 0.8mT and 1.5mT, were applied to the reactor including several neodymium magnets. The methodology for gathering and analysis of the data lead to a steady state for the reactor. To confirm validity, results and conclusions from other relatable studies were compared with the results of the present study. The research lasted approximately 100 days and sampling was completed over an 80 day period to observe the effects when implementing a magnetic field compared to that of its absence within an Orbal reactor. This study examined the removal of COD in activated sludge. Results revealed that removal of COD was significantly affected when implementing the magnetic field. Upon application of a 0.8mT magnetic field, removal efficiency of COD increased by 7%, Results also indicated that use of different power magnetic fields had very insignificant differences.
Keywords
Magnetic field
activated sludge
Orbal oxidation reactor
COD removal
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  • Receive Date 29 December 2021
  • Revise Date 08 March 2022
  • Accept Date 13 March 2022