شبیه‌سازی CFD هیدرودینامیک راکتور حبابی- دوغابی همزن‌دار تولید ترفتالیک اسید پتروشیمی شهید تندگویان

نوع مقاله: مقاله پژوهشی

نویسندگان

دانشکده مهندسی شیمی، دانشگاه علم و صنعت ایران، تهران، ایران

چکیده

در این مقاله اثر جهت همزن بر رفتار هیدرودینامیکی و نحوه هوادهی اسپارجرهای راکتور واحد ترفتالیک اسید پتروشیمی شهید تندگویان شبیه‌سازی گردیده است. شبیه‌سازی‌ها با رویکرد چندفازی اولرین-اولرین، مدل اغتشاش RNG k-ε به صورت ناپایا، سه بعدی و توسط نرم‌افزار Fluent 6.3.26 انجام گرفت. معادلات حاکم به روش حجم محدود برای تمام دامنه محاسباتی سیستم حل گردید و جهت شبیه‌سازی رفتار همزن در راکتور از مدل قاب چرخان استفاده شد. از آنجائی‌که هوای فشرده از پایین راکتور توسط چهار اسپارجر تزریق می‌شود، نتایج شبیه‌سازی نشان داد، همزن توربینی با جریان بالارونده سبب افزایش زمان ماند حباب‌ها و شدت اختلاط در بالای راکتور می‌شود. همچنین بیشتر انرژی این همزن صرف حرکت سیال شده و مقدار کمی از آن صرف اختلاط فازها می‌شود. برای همزن توربینی با جریان پایین رونده، جریان مایع، گاز خروجی از اسپارجرها را در خلاف جهت منحرف کرده و جریان گاز را به مرکز راکتور هدایت می‌کند.
 

کلیدواژه‌ها


عنوان مقاله [English]

A CFD Simulation of Agitated Slurry-bubble CTA Production Reactor of Shahid Tondgooyan Petrochemical Complex (STPC)

نویسندگان [English]

  • Sadegh Pahlevani
  • Seyyed Hasan Hashemabadi
  • Amir Heidari
Computational Fluid Dynamic Laboratory, Chemical Engineering Department, Iran University of Science and Technology, Tehran
چکیده [English]

this work, agitated slurry-bubble reactor was simulated with the aid of computational fluid dynamics techniques. The effects of impeller flow direction on hydrodynamic behavior and the aeration quality of reactor spargers (terephthalic acid CTA, production in Shahid Tondgooyan petrochemical complex) were investigated. To this aim, an Eulerian multiphase approach and RNG k-ε turbulence model were employed for large-scale CFD simulations. The results showed that up-flow impeller caused an increase in bubble residence time and mixing intensity in the higher zones of the reactor. Therefore, the length of the liquid path and the number of direction changes were greater in the case of up-flow impeller compared to down-flow one. As a result, the energy associated with the down-flow impeller (at the bottom of reactor) was much higher than the up-flow one; hence the turbulence intensity for the down-flow impeller was also relatively high. For down flow pattern, the outlet gas of spargers caused a reverse flow by the liquid flow and pushed the gas to the reactor center.
 

کلیدواژه‌ها [English]

  • Agitated Slurry Bubble Reactor
  • Computational Fluid Dynamics (CFD)
  • Pseudo Two-phase Approach
  • RNG k-ε Turbulence Model
 

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