کارایی فرایند انعقاد الکتریکی در تصفیه آب سطحی با استفاده از الکترود آلومینیوم

نوع مقاله: مقاله پژوهشی

نویسندگان

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

2 دانش‌آموخته کارشناسی ارشد مهندسی بهداشت محیط، عضو مرکز تحقیقات توسعه اجتماعی و ارتقاء سلامت، دانشگاه علوم پزشکی کرمانشاه، کرمانشاه، ایران

3 دانشیار، گروه مهندسی بهداشت محیط، عضو مرکز تحقیقات عوامل محیطی مؤثر بر سلامت، دانشگاه علوم پزشکی کرمانشاه، کرمانشاه، ایران

4 دانشیار، دانشکده شیمی، دانشگاه رازی، کرمانشاه، ایران

5 دانشیار، گروه مهندسی بهداشت محیط، عضو مرکز تحقیقات ارتقاء سلامت، دانشگاه علوم پزشکی زاهدان، زاهدان، ایران

چکیده

دسترسی به آب آشامیدنی سالم یکی از اهداف مهم برای حفظ بهداشت عمومی است. این پژوهش، یک مطالعه توصیفی- مقطعی بود که با هدف بررسی عملکرد فرایند انعقاد الکتریکی در تصفیه آب سطحی انجام شد. نمونه‌های آب از آبگیر سد سلیمانشاه سنقر تهیه شدند. فرایند تصفیه در یک راکتور به‌صورت ناپیوسته انجام شد. طراحی دوره‌های آزمایش با استفاده از نرم‌افزار دیزاین اکسپرت انجام شد. اثر متغیرهای پتانسیل الکتریکی (5 تا 25 ولت)، زمان واکنش (20 تا 60 دقیقه)، دما ( 10 تا 30 درجه سلسیوس) و دور همزن (200 تا 400 دور دقیقه) بر راندمان حذف آهن، منگنز، سختی، قلیائیت و کدورت از آب سطحی با استفاده از الکترود آلومینیوم بررسی شد. بعد از تصفیه، پارامترهای مورد مطالعه و مقادیر فلز محلول ناشی از آزادسازی الکترود آند اندازه‌گیری شد. در تصفیه با فرایند انعقاد الکتریکی حداکثر راندمان حذف آهن 2/96 درصد، منگنز 6/94 درصد، سختی 6/26 درصد و قلیائیت 2/12 درصد به‌دست آمد و کدورت از 6/0 به NTU15/0 کاهش یافت. در این شرایط مقدار فلز محلول آلومینیوم بیشتر از سطح استاندارد آب آشامیدنی بود. نتایج نشان داد که فرایند انعقاد الکتریکی در حذف پارامترهای مورد بررسی از آب سطحی مؤثر است. مقدار فلز محلول در اثر انحلال الکترود آند حائز اهمیت بهداشتی است و استفاده از این روش را در شرایط حداکثر راندمان حذف محدود می‌کند. در شرایط بهینه، فرایند انعقاد الکتریکی با الکترودهای آلومینیوم، یک روش پیش‌تصفیه مناسب است.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Performanc of Electrocoagulation (Using Al Electrodes) in Surface Water Treatment

نویسندگان [English]

  • jamshid derayat 1
  • zeinab jafarimotlagh 2
  • meghdad pirsaheb 3
  • aliakbar zinatizadeh 4
  • Edris Bazrafshan 5
1 Ass. Prof. of Environmental Health Engineering, Faculty of Public Health, Kermanshah University of Medical Sciences, Kermanshah, Iran
2 Former Graduate Student of Environmental Engineering, Member of Social Development and Health Promotion Research Center, Kermanshah University of Medical Sciences, Kermanshah, Iran
3 Assoc. Prof. of Environmental Health Engineering, Member of Research Center for Environmental Determination of Health (RCEDH), Kermanshah University of Medical Sciences, Kermanshah, Iran
4 Assoc. Prof., Dept. of Chemistry, Razi University, Kermanshah, Iran
5 Assoc. Prof of Environmental Health Engineering, Member of Health Promation Research Center, Zahedan University of Medical Sciences, Zahedan, Iran
چکیده [English]

Access to safe drinking water is an important means of safeguarding public health. This cross-sectional study was designed to investigate the performance of electrocoagulation in the treatment of surface waters. For this purpose, water samples were taken from the intake to the Soleymanshah-Songhor Dam. Treatment was carried out in a reactor operating in the batch mode. Experiment runs were designed using the Design Expert Software (Stat-Ease Inc., Version 6.0.6) to investigate the effects of voltage (5-25), reaction time (20-60), temperature (10-30Ċ), and rapid mixing (200-400) on the Mn (II), Fe (II), hardness, alkalinity, and turbidity removal efficiencies as a result of treatment with aluminum electrodes. After the treatment process, the study parameters and the dissolved metal content due to the dissolution of the anode electrode were measured. Maximum removal efficiencies for Fe (II), Mn (II), hardness, and alkalinity were 96.2%, 94.6%, 26.6%, and 12.2%, respectively, while turbidity reduced from 0.6 to 0.15 NTU. Moreover, the dissolved Al content in the treated sample was found to be higher than the standard limit allowed for drinking water. Thus, the electrocoagulation process seems to be effective in the removal of the investigated contaminants from surface waters. However, the factor limiting the use of this method under maximum efficiency conditions is the dissolved metal content due to the dissolution of the anode electrode, which is a significant concern for the public health. In contrast, the electrocoagulation process seems to be an efficient and safe pretreatment method using aluminum electrodes if operated for achieving optimum efficiencies.

کلیدواژه‌ها [English]

  • Electrocoagulation
  • Surface water
  • Aluminum Electrode
  • Water Treatment

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