بررسی تاثیر میدان مغناطیسی ثابت بر راندمان حذف COD از منابع آب در سیستم تصفیه اربال

نوع مقاله : مقاله پژوهشی

نویسندگان

1 گروه مهندسی محیط زیست، دانشکده محیط زیست و انرژی، دانشگاه علوم تحقیقات، تهران، ایران

2 گروه علوم دریایی، دانشکده منابع طبیعی و محیط زیست ، دانشگاه آزاد اسلامی واحد علوم تحقیقات، تهران ، ایران

3 گروه مهندسی و محیط زیست، واحد علوم و تحقیقات، دانشگاه آزاد اسلامی

چکیده

با توجه به نیاز روزافزون انسان به تصفیه منابع آب و استفاده مجدد از آن، بهبود عملکرد روش‌های تصفیه آب و افزایش راندمان آن بسیار موردتوجه قرار دارد. استفاده از راکتور اربال برای حذف COD به‌وسیلة لجن فعال در گذشته در تحقیقات متعدد توصیه شده است. علاوه‌براین، پیدا کردن روش‌ها و ابزار جدید به‌منظور افزایش بازده این سیستم بسیار موردتوجه است. در این مقاله تأثیر وجود میدان مغناطیسی در راکتور اربال و تأثیر آن بر راندمان حذف COD بررسی شده است. بدین منظور در گام نخست با راه‌اندازی یک پایلوت در ابعاد آزمایشگاهی و رساندن آن به شرایط پایدار، راندمان سیستم در حذف COD در شرایط ایده‌آل به‌دست آمد. در ادامه دو میدان مغناطیسی با شدت‌های مختلف (mT8/0 وmT 5/1) در پایلوت ایجاد شد. این آزمایش در مدت 100 روز انجام شد و در یک دوره 80 روزه به‌منظور مشاهده تفاوت بین وجود و نبود میدان مغناطیسی در راندمان حذف COD نمونه‌برداری انجام شد. پس از تحلیل نتایج تفاوت معناداری در خروجی راکتور پس از اعمال میدان مشاهده شد و راندمان راکتور حدود 7% بهبود پیدا کرد. البته لازم به بیان است، تفاوت چندانی در خروجی‌های به‌دست‌آمده از دو میدان مغناطیسی با شدت‌های مختلف مشاهده نشد.

کلیدواژه‌ها


عنوان مقاله [English]

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

نویسندگان [English]

  • Hooman Ghahremanzadeh 1
  • Sara Allahyaribeik 2
  • Amirhossein Javid 3
  • 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
3 Department of Environmental Engineering, Faculty of natural Resources and Environment, Science and Research Branch, Islamic Azad University, Tehran, Iran
چکیده [English]

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.

کلیدواژه‌ها [English]

  • Magnetic field
  • activated sludge
  • Orbal oxidation reactor
  • COD removal
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