اثر شرایط عملیاتی و خواص خوراک بر محتوای گوگرد محصول مایع حاصل از شکست حرارتی ته‌مانده برج تقطیر خلأ و مدل‌سازی سینتیکی واکنش‌های ترکیبات گوگردی

نوع مقاله: مقاله پژوهشی

نویسندگان

دانشگاه تربیت مدرس، دانشکده مهندسی شیمی

چکیده

در این تحقیق شکست حرارتی ته‌مانده برج تقطیر خلأ پالایشگاه‌های تهران و بندرعباس مورد مطالعه قرار گرفته است. محتوای گوگرد محصول مایع یکی از مهم‌ترین شاخص‌های کیفیت این محصول می‌باشد. اثر عوامل مختلف در غلظت گوگرد محصول اصلی فرایند (برش مایع) مطالعه شده است. برای هر دو خوراک، حداکثر حدود 25% از گوگرد خوراک وارد محصول مایع شده است. با افزایش دمای فرایند، غلظت گوگرد در محصول مایع افزایش یافت. این در حالی است که با افزایش زمان ماند در یک دمای معین، غلظت گوگرد مایع کاهش می‌یابد. در نهایت تأثیر خواص فیزیکی- شیمیایی خوراک (مقدار گوگرد، دانسیته، کربن باقی‌مانده و نسبت هیدروژن به کربن) بر مقدار گوگرد محصول مایع بررسی شده است. مدلی برای واکنش‌های ترکیبات گوگردی ارائه و براساس آن مدل‌سازی سینتیکی این واکنش‌ها انجام شده است. ثوابت سینتیکی برای هر یک از خوراک‌ها تعیین شده است. درجه واکنش‌های تولید گوگرد مایع نزدیک به 2 و درجه ‌واکنش‌های تولید گوگرد گازی نزدیک به 3 محاسبه گردید.

کلیدواژه‌ها


عنوان مقاله [English]

Effect of Operating Conditions and Physical Properties of the Feed on Sulfur Content of the Liquid Product in Thermal Cracking of Vacuum Residue and its Kinetic Modeling

نویسندگان [English]

  • Saeid Abbasi Aliabadi
  • Ramin Karimzadeh
  • Mohammad Ghashghaee
  • Reza Asgharzadeh Shishavan
Chemical Engineering Faculty, Tarbiat Modares University
چکیده [English]

In this study, thermal cracking of two vacuum residues (VRs) from Tehran and Bandar Abbas refineries has been carried out. The products of this process consist of gas, liquid, and quasi-coke residue. Coke formation and the high sulfur content of products are the most difficulties that VR upgrading processes are faced with. The distribution of sulfur among these products has been studied. The investigation of the effect of operating conditions on the sulfur content of the liquid product has proven that sulfur concentration in the liquid fraction increases with temperature, while longer residence time can dilute the sulfur compounds and lessen their concentrations in the liquid product. The product of Bandar Abbas VR has a higher sulfur concentration relative to Tehran VR. It was shown that the liquid products, containing a high sulfur concentration, have higher densities and refractive indexes. On the other hand, higher process temperatures result in a greater production of the more desirable (liquid) product accompanied by lowering its quality. The effect of physicochemical properties of the VRs (sulfur content, density, Conradson Carbon Residue and H/C ratio) on the sulfur content of the liquid product has also been investigated. The kinetic modeling of reactions of sulfur compounds has been implemented for both VRs. Kinetic constants at different temperatures are given on the basis of the experimental results.

کلیدواژه‌ها [English]

  • Thermal Cracking
  • Vacuum Residue
  • Sulfur Concentration
  • Kinetics
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