بررسی پتانسیل کرم‌های توبیفکس در کاهش جرم و حجم لجن تصفیه‌خانه‌های فاضلاب در مقیاس آزمایشگاهی

نوع مقاله: مقاله پژوهشی

نویسندگان

1 دانشجوی کارشناسی ارشد مهندسی عمران محیط زیست، دانشگاه تربیت مدرس، تهران

2 دانشیار دانشکده مهندسی عمران و محیط زیست، دانشگاه تربیت مدرس، تهران

3 استاد دانشکده مهندسی عمران و محیط زیست، دانشگاه تربیت مدرس، تهران

چکیده

در تصفیه‌خانه‌های فاضلاب حجم زیادی از لجن مازاد بیولوژیکی تولید می‌شود که هزینه فرایند تصفیه و دفع آن تقریباً نیمی از کل هزینه بهره‌برداری از تصفیه‌خانه است. در این تحقیق سعی بر آن شد تا در مقیاس آزمایشگاهی به‌کمک روشی نسبتاً کم هزینه‌تر و با صرف انرژی کمتر، میزان حجم و جرم لجن کاهش داده شود. لذا با ایجاد شرایط زیستی مطلوب و رشد و تکثیر کرمهای نوع توبیفکس در بستر لجن که نوع متداول کرم در تصفیه‌خانه فاضلاب است، سپس با اندازه‌گیری TSS، VSS و میزان رشد کرمها، مقدار کاهش جرم و حجم تعیین شد. در این روش با حضور کرمها با ضریب رشد 05/0 بر روز، روند کاهش VSS معادل  26 میلی‌گرم در لیتر در روز، کاهش TSS و حجم لجن با مقدار اولیه  2850 میلی‌گرم در لیتر و 2000 لیتر به‌ترتیب معادل 40 و 20 درصد مشاهده شد. همچنین COD محلول با مقدار اولیه 500 میلی‌گرم در لیتر تا 50 درصد در شرایط آزمایش کاهش یافت.

کلیدواژه‌ها


عنوان مقاله [English]

Investigation of Tubifex Worms Potential in Mass and Volume Reduction of Sludge Wastewater Treatment Plants in Laboratory Scale

نویسندگان [English]

  • Samaneh Pasha Zanousi 1
  • Bita Ayati 2
  • Hossein Ganjidoost 3
چکیده [English]

Large amount of excess waste from activated sludge is generated in wastewater treatment plants which its treatment, transportation and disposal costs are estimated to be over 50 percent of total  plant cost operation. In this research it was tried to decrease the amount of sludge volume and its mass by using relative low cost and low energy consumed  process in laboratory scale. By developing suitable environmental conditions and population increase and growth of aquatic Tubifex worms in sludge (conventional kinds of worms in wastewater treatment plants) and with measurement of TSS, VSS and worms growth rate, sludge mass and volume reduction were determined. According to the results, in specific growth rate of 0.05 d-1, VSS reduction of 26 mg/l.d and with initial sludge amount of 2850 mg/l and 2000 mg/l, TSS and sludge volume reduction of 40 and 20 percent were observed, respectively. 50 percent of soluble COD with initial amount of 500 mg/l was also removed in the laboratory conditions.

کلیدواژه‌ها [English]

  • Tubifex
  • Sludge
  • COD
  • TSS
  • VSS
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