مشخصه‌یابی فیزیکی و شیمیایی رسوب چربی و روغن موجود در خطوط فاضلاب شهر مشهد و راه‌های جلوگیری از آن

نوع مقاله : مقاله پژوهشی

نویسندگان

1 مربی مرکز پژوهشی مهندسی فرایند، دانشگاه اصفهان و دانشجوی دکترای مهندسی آب و فاضلاب، دانشکده مهندسی محیط زیست، دانشگاه تهران

2 دانش‌آموخته کارشناسی‌ارشد مهندسی شیمی، گروه مهندسی شیمی، دانشکده فنی مهندسی، دانشگاه اصفهان

3 کارشناس مهندسی آب و فاضلاب، شرکت آب و فاضلاب مشهد

4 استادیار گروه زیست‌فناوری، دانشکده علوم و فناوری‌های نوین، دانشگاه اصفهان

چکیده

رسوب‌های ناشی از روغن، چربی و گریس در خطوط فاضلاب باعث سرریز فاضلاب، آسیب به محیط زیست و خطرات بهداشتی می‌شود. آنالیز دو نمونه رسوب جمع‌آوری شده از شبکه‌ فاضلاب خیابان امام رضا (ع) در شهر مشهد، نشان داد که واکنش‌های شیمیایی روغن‌های خوراکی در خطوط فاضلاب، منجر به تشکیل صابون غیر محلول و ایجاد رسوب در خطوط فاضلاب می‌شود. این رسوب‌ها به‌‌دلیل چسبندگی زیاد به مرور زمان درون لوله جمع و موجب انسداد آن می‌شود. رطوبت این نمونه‌ها 50 و 62 درصد است که نشان می‌دهد آب نقش اساسی در تشکیل آن‌ها ندارد. مقدار اسید چرب اشباع نمونه‌ها 78/61 و 35/84 درصد و اسید چرب اشباع غالب، اسید پالمیتیک است. کلسیم مهم‌ترین فلز حاضر در این نمونه‌ها است که هم از راه سختی آب و هم خوردگی لوله‌های فاضلاب ایجاد می‌شود. با توجه به نتایج به‌دست‌آمده و منشأ ایجاد این رسوب‌ها، راه‌حل‌هایی برای جلوگیری از ایجاد رسوب و انسداد خطوط فاضلاب بر اساس دستورالعمل مدیریت روغن و چربی با در نظرگرفتن شرایط محیطی و فرهنگی منطقه پیشنهاد شده است. این پیشنهادها در حال بررسی و ابلاغ برای اجرا است.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Physical and Chemical Characterization of Fat and Oil Deposits in Mashhad City Sewer Lines and the Solutions Developed

نویسندگان [English]

  • Mahdi kamali 1
  • Majid Pirooz 2
  • Jalil Jalilian 3
  • Mohammadali Asadollahi 4
1 Lecturer, Institute of Process Engineering, University of Isfahan, and PhD Student of Water and Wastewater Engineering, Graduate Faculty of Environment, Department of Environmental Engineering, University of Tehran
2 MSc of Chemical Engineering, Department of Chemical Engineering, Faculty of Engineering, University of Isfahan
3 BS of Water and Wastewater Engineering, Mashhad Water and Wastewater Company, Mashhad
4 Ass. Prof. of Biotechnology, Department of Biotechnology, Faculty of Advanced Sciences and Technologies, University of Isfahan, Isfahan
چکیده [English]

Formation of oil, fat, and grease deposits in sewer pipelines is a major concern as they result in sewage overflow and pose health problems. Analysis of two sample deposits collected from the sewer lines of Imam Reza Street in the city of Mashhad suggested that the chemical reactions promoted by edible oils in the sewer lines lead to the formation of insoluble soap and deposits. Being sticky, the deposits accumulate over time to eventually block the lines. The analysis also showed that the moisture content of the samples ranged between 50‒62%, indicating that water does not play a main role in their formation. The samples were also found to contain 61.78% and 84.35% saturated fatty acids, with palmitic acid being the dominant one. Calcium was the main metal in the samples, which is due to both water hardness and corrosion of the sewer lines. Based on the results obtained, the origin of these deposits, and the relevant protocols for the management of oil and fat wastes, solutions were proposed to prevent deposit formation and sewer line clogging that suit the special cultural and environmental conditions of the city. These proposals are under consideration for implementation in the region.

کلیدواژه‌ها [English]

  • Physical and Chemical Characterization
  • fat
  • Oil and Grease Deposits
  • Sewer Lines Blockage Prevention
  • FOG Managements
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