کاربرد روش سطح پاسخ برای مدل‌سازی و بهینه‌سازی فرایند انعقاد در حذف یون بروماید

نوع مقاله : مقاله پژوهشی

نویسندگان

1 دانشجوی کارشناسی ارشد مهندسی شیمی، دانشگاه محقق اردبیلی

2 استادیار گروه مهندسی شیمی، دانشگاه محقق اردبیلی

چکیده

در این پژوهش با استفاده از روش سطح پاسخ و طراحی مرکب مرکزی، کارایی فرایند انعقاد در حذف یون بروماید، مدل‌سازی و بهینه‌سازی شد. یون بروماید در آب‌های سطحی به‌طور طبیعی یافت می‌شود و علی‌رغم غیرسمی بودن آن، این یون در برخورد با گندزداهای رایج تصفیه آب، باعث تولید محصولات جانبی گندزدایی با سرطان‌زایی بیشتر نسبت به ‌نوع کلرینه آنها می‌شود. فرایند انعقاد در تصفیه‌خانه‌های آب، به‌عنوان یک قسمت کلیدی تلقی می‌شود. انعقاد پیشرفته که به‌تازگی با کمک منعقد کننده‌های جدیدی با عنوان منعقد کننده‌های پلیمری معدنی، توانایی قابل ‌توجهی در حذف کدورت و انعقاد ذرات کلوئیدی و کاهش پتانسیل زتا دارند، در پژوهش‌ها مورد توجه قرار گرفته‌اند. منعقد کننده استفاده شده در این سری آزمایش‌ها، پلی‌آلومینیوم‌کلراید بود. با استفاده از طراحی آزمایشی که توسط نرم‌افزار دیزاین اکسپرت انجام شد، مدل بسیار خوبی با  ضریب رگرسیونی برابر 9925/0 به اطلاعات حاصل از مشاهدات تجربی در راندمان حذف بروماید فیت شد. پارامترهای غلظت اولیه بروماید و دز منعقد کننده، تأثیر مستقیمی بر راندمان حذف یون بروماید داشت؛ ولی برای pHرفتار متفاوتی مشاهد شد.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Application of Response Surface Methodology (RSM) for Modeling and Optimizing Coagulation Process for the Removal of Bromide Ions

نویسندگان [English]

  • Mohammad Abdollahpour 1
  • keivan shayesteh 2
1 MSc Student in Chemical Engineering, Mohaghegh-e-Ardabili University, Ardabil
2 Ass. Prof. of Chemical Engineering, Mohaghegh-e-Ardabili University, Ardabil
چکیده [English]

In this paper, the response surface methodology and the central composite design are used to model and optimize bromide removal efficiency in the coagulation process. Bromide ions are naturally found in surface waters. Despite its non-toxicity, when exposed to disinfectants commonly used in water treatment, bromide ions produce disinfection byproducts which are more carcinogenic than their chlorinated counterparts. A key process in water treatment is coagulation. Most studies have recently focused on enhanced coagulation achieved by new coagulants known as inorganic polymer coagulants which exhibit a remarkable ability in both removing colloidal particles and reducing turbidity and the zeta potential from water. In the present experiments, poly-aluminum chloride (PAC) is used as a coagulant. Moreover, an experimental design is constructed using the Design-Expert software to develop an efficient model with a regression coefficient of 0.9925 which fitted the observed data on bromide removal efficiency. It is found that coagulant dosage and initial bromide concentration have direct impacts on bromide removal efficiency while a different behavior is observed in the case of pH.

کلیدواژه‌ها [English]

  • Response Surface Methodology
  • Central composite design
  • Enhanced coagulation
  • Bromide Ion
  • Poly-Aluminum Chloride
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