بررسی کارایی فرایند انعقاد الکتریکی در حذف مجموع کلیفرم‌ها و باکتری‌های هتروتروف از آب سطحی

نوع مقاله: مقاله پژوهشی

نویسندگان

1 استادیار گروه بهداشت محیط، دانشکده بهداشت، دانشگاه علوم پزشکی کرمانشاه

2 دانشیار گروه بهداشت محیط، عضو مرکز تحقیقات سلامت، دانشگاه علوم پزشکی کرمانشاه

3 دانشجوی کارشناسی ارشد، عضو مرکز تحقیقات توسعه اجتماعی و ارتقاء سلامت، دانشگاه علوم پزشکی کرمانشاه

4 استادیار گروه شیمی کاربردی، دانشکده شیمی، دانشگاه رازی، کرمانشاه

چکیده

انعقاد الکتریکی یک روش الکتروشیمیایی برای تصفیه آب و فاضلاب است. هدف از این تحقیق بررسی راندمان حذف مجموع کلیفرم‌ها و باکتری‌های هتروتروف از آب‌های سطحی با استفاده از فرایند انعقاد الکتریکی بود. این تحقیق یک مطالعهتوصیفی- مقطعی بود. نمونه‌های آب از آبگیر آب آشامیدنی سد سلیمانشاه سنقر تهیه شدند. فرایند انعقاد الکتریکی در یک راکتور از جنس پلکسی گلاس به‌صورت بسته و با الکترودهای آلومینیوم و آهن انجام شد. طراحی دوره‌های بارگذاری با استفاده از نرم‌افزارDesign expert انجام شد. بعد از هر دوره، مقادیر فلز محلول ناشی از آزادسازی الکترود آند با دستگاه  ICPاندازه‌گیری شد و نتایج با مدل RSM مورد تحلیل قرار گرفت. نتایج این مطالعه نشان داد که بالاترین راندمان حذف مجموع کلیفرم‌ها و باکتری‌های هتروتروف با استفاده از الکترود آلومینیوم به‌ترتیب 100 و 1/89 درصد است. همچنین با استفاده از الکترود آهن، بالاترین راندمان حذف مجموع کلیفرم‌ها و باکتری‌های هتروتروف به‌ترتیب 100 و 1/76 درصد به‌دست آمد. با این وصف مقادیر آزادسازی فلزات محلول آهن و آلومینیوم فراتر از سطح استانداردهای آب آشامیدنی بود. نتایج نشان داد که فرایند انعقاد الکتریکی روشی مؤثر در حذف عوامل میکربی از آب‌های سطحی است. مقادیر فلز محلول در اثر انحلال الکترود آند، حائز اهمیت بهداشتی است، بنابراین باید شرایط بهینه با توجه به غلظت مجاز فلز مذکور انتخاب شود.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Performance of Electrocoagulation Process in the Removal of Total Coliform and Hetrotrophic Bacteria from Surface Water

نویسندگان [English]

  • Jamshid Derayat 1
  • Meghdad Pirsaheb 2
  • zeinab jafarimotlagh 3
  • Aliakbar Zinatizadeh 4
چکیده [English]

Electrocoagulation is an electrochemical method for the treatment of water and wastewater. The present cross-sectional study was designed to investigate the removal efficiency of total coliform and heterotrophic bacteria from surface water using the process. For this purpose, water samples were taken from the drinking water intake at Suleiman-Shahsonghur Dam. The electrocoagulation process was carried out in a Plexiglas reactor in the batch mode with Al and Fe used electrodes. The experiment design was carried out using the Design Expert Software (Stat-Ease Inc., Ver. 6.0.6). After each run, the values of metals dissolved due to anode electrode dissolution were measured using the Inductively Coupled Plasma (ICP) and the results were analyzed using the RSM model. Results revealed maximum removal efficiencies of 100% and 89.1% for total coliform and heterotrophic bacteria using the Al electrode, respectively. Also, maximum removal efficiencies using the Fe electrode for the same pollutants were 100% and 76.1%. The measurements clearly indicate that the quantities of Al and Fe released in water were higher than the recommended values. While the electrocoagulation process showed to be effective in removing microbial agents from surface waters, the high concentrations of dissolved metals due to the dissolution of the anode electrode seem to remain a health problem that requires optimal conditions to be determined for acheiving standard concentrations of the dissolved metals.

کلیدواژه‌ها [English]

  • Electrocoagulation
  • Surface Waters
  • Coliform
  • Hetrotrophic Bacteria
  • Sonqur

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