تأثیر پارامترهای مهم بر فرآیندهای آناموکس و شارون در تصفیه پساب نیتروژنی

نوع مقاله: مقاله مروری

نویسندگان

1 کارشناسی ارشد، گروه مهندسی شیمی، دانشکده مهندسی، دانشگاه فردوسی، مشهد، ایران

2 استاد، گروه مهندسی شیمی، دانشکده مهندسی، دانشگاه فردوسی، مشهد، ایران

3 کارشناسی، گروه مهندسی شیمی، دانشکده مهندسی شیمی- نفت و گاز، دانشگاه شیراز، شیراز، ایران

چکیده

به­دلیل مخاطرات زیست محیط‌، تصفیه پساب‌های نیتروژنی امری ضروری و مهم می‌باشد. طی دهه‌های اخیر، فناوری‌های جدید بیولوژیکی نظیر آناموکس و شارون توسعه یافتند که نسبت به فرآیندهای مرسوم، ارزان‌تر و مؤثرترند. در این تحقیق، تعدادی از پارامترهای زیست‌محیطی تأثیرگذار بر این فرآیندها نظیر دما، pH، اکسیژن محلول، کربن آلی، غلظت نمک، غلظت نیتریت و زمان‌ماند لجن (SRT) مورد بررسی قرار گرفتند. نتایج تحقیقات نشان­داد که فرآیند شارون نیاز به منبع کربنی را کاهش می‌دهد؛ درحالی‌که فرآیند آناموکس بدون نیاز به منبع کربنی، تحت شرایط بی‌هوازی انجام می‌شود. مقدار بهینه pH برای فرآیند آناموکس 3/8-7/6 گزارش ‌شده­بود. غلظت نیتریت و نمک پارامترهای کنترلی مهمی در جلوگیری از فعالیت باکتری‌های آناموکس هستند. دمای مطلوب برای رشد باکتری‌های آناموکس ℃ 40-30 و برای فرآیند شارون بیشتر از ℃ 25 می‌باشد. راندمان فرآیندها به‌صورت خطی با SRT متناسب نبودند. به‌طورکلی، فرآیندهای جدید بیولوژیکی حذف نیتروژن با کاهش نیاز به هوادهی و منابع کربنی امیدبخش توصیف شدند و جایگزین مناسبی برای فرآیندهای مرسوم می‌باشند.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Impact of key factors on ANNAMOX and SHARON processes in nitrogenous effluent treatment

نویسندگان [English]

  • Seyed Mohammad Ali Masoudi 1
  • Javad Sargolzaie 2
  • Seyed Ardavan Hoseini 3
1 M.Sc., Department of Chemical Engineering, Faculty of Engineering, Ferdowsi University of Mashhad, Mashhad, Iran
2 Professor, Department of Chemical Engineering, Faculty of Engineering, Ferdowsi University of Mashhad, Mashhad, Iran
3 B.Sc., Department of Chemical Engineering, School of Chemical- Petroleum & Gas Engineering, Shiraz University, Shiraz, Iran
چکیده [English]

Due to the environmental hazards, nitrogenous wastewater treatment is essential and important. In recent decades, novel biological processes such as Annamox and SHARON have developed which are cheaper and more effective compared to conventional processes. In the present study, several significant biological parameters such as temperature, pH, dissolved oxygen, organic carbon, salt concentration, nitrite concentration and sludge retention time (SRT) were investigated. The results showed that SHARON process lowered the need for carbon source while Annamox process without carbon source requirement, was implemented in anaerobic condition. The optimum pH for Annamox process was reported 6.7-8.3. Nitrite and salt concentrations were important control parameters to prevent Annamox bacterial activity. Desired temperature for the bacterial growth was 30-40℃  for Annamox and higher than 25℃ for SHARON, and process efficiencies were not directly related to SRT. Overall, the new biological processes of nitrogen removal were described promising due to the decrease in need for aeration and carbon source and are suitable alternatives for conventional processes.

کلیدواژه‌ها [English]

  • Wastewater Treatment
  • Anaerobic
  • SHARON
  • ANNAMOX
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