شبیه‌سازی راکتور فتوکاتالیستی به روش حجم محدود و جهت‌های مجزا و مطالعات پارامتریک

نوع مقاله : مقاله پژوهشی

نویسندگان

1 کارشناسی ارشد دانشکده مهندسی شیمی دانشگاه صنعتی امیرکبیر

2 عضو هیات علمی، دانشکده مهندسی شیمی، دانشگاه صنعتی امیرکبیر

3 عضو هیات علمی دانشکده مهندسی شیمی دانشگاه تهران

چکیده

استفاده از روش‌های اکسیداسیون پیشرفته برای تصفیه آب به تازگی بسیار مورد توجه بوده ‌است. تصفیه فتوکاتالیستی آب با استفاده از نانوکاتالیست تیتانیوم دی‌اکسید و نور فرابنفش منجر به تجزیه آلودگی‌های آب می‌شود. با وجود پژوهش‌های تجربی بسیار زیاد، طراحی و مدل‌سازی راکتور‌های فتوکاتالیستی همچنان یک چالش است. یکی از راه‌حل‌های موثر برای دستیابی به این مهم استفاده از دینامیک سیالات محاسباتی است. از عوامل موثر بر بازده راکتور فتوکاتالیستی، نحوه عملکرد کاتالیست است که توسط نور فرابنفش فعال می‌شود. در صورت عدم پخش مناسب نور فرابنفش درون راکتور، بخشی از راکتور به دلیل فعال نشدن کاتالیست کارایی نداشته و بازده کاهش می‌یابد. در این کار راکتور شبیه‌سازی شده با داده‌های آزمایشگاهی اعتبارسنجی و سپس اثر غلظت کاتالیست، توان لامپ و انعکاس دیواره بررسی گردید. طبق نتایج با افزایش انعکاس دیواره به میزان ۹۸ درصد در غلظت 4/0 گرم بر لیتر کاتالیست، نرخ واکنش به میزان 50 درصد افزایش می‌یابد. با افزایش توان لامپ به دو برابر، میزان نرخ واکنش در حالت دیواره با انعکاس 98 درصد در مقایسه با دیواره با انعکاس صفر، به میزان 2/12 درصد، افزایش می‌یابد که در مقایسه با افزایش 11 درصد در حالت معمولی توان لامپ، به معنای افزایش 2/1 درصدی است.
 

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Simulation of a Photocatalytic Reactor Using Finite Volume and Discrete Ordinate Method: A Parametric Study

نویسندگان [English]

  • Majede Nourizade 1
  • Mohammad Rahmani 2
  • Aliyar Javadi 3
1 MSc Chemical Eng Dep Chemical Engineering Department Amirkabir Uni of Technology
2 Faculty member, Chemical Engineering Department, Amirkabir University of Technology
3 faculty member Chemical Engineering Department Tehran University
چکیده [English]

Advanced oxidation processes for wastewater treatment have received recently a great deal of attention. Photocatalytic oxidation processes decompose water pollutants using nano-structured photocatalyst materials, titanium dioxide, and ultraviolet irradiation. Although there is extensive experimental research in this field, designing a photoreactor is still a challenge. An effectual approach to this issue is the application of computational fluid dynamics. The performance of the catalyst, which is activated by ultraviolet irradiation, is one of the important factors affecting photoreactor efficiency. In the case of poor ultraviolet radiation distribution inside the reactor, the performance decreases due to catalyst inactivity. In this study, a computational fluid dynamics model for the simulation of radiation distribution inside a photoreactor was developed and evaluated against experimental data. Simulations were then carried on different catalyst loading, lamp power and wall reflectivity. The result showed that at a low concentration of catalyst (0.4 g/l), the reaction rate increases by up to 50% by increasing the wall reflectivity to 98%. At the lamp power of 2p < /em> and p < /em>, the reaction rate increases by up to 12.2 % and 11% respectively, meaning only a 1% increase in reaction rate while increasing lamp power.

کلیدواژه‌ها [English]

  • Photocatalytic Reactor
  • Wastewater treatment
  • Simulation
  • Computational fluid dynamics
  • Catalyst
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