بررسی اثر فشار بر میزان ماندگی گاز در راکتورهای حبابی و دوغابی

نوع مقاله : مقاله پژوهشی

نویسندگان

واحد تبدیلات گازی، پژوهشکده گاز، پژوهشگاه صنعت نفت

چکیده

در صنعت، معمولاً ستون راکتورهای حبابی و دوغابی در فشارهای بالای اتمسفری در حدود Bar ا7-35 کار می‌کنند. با وجود بررسی‌های زیادی که در مورد ستون‌های حبابی و دوغابی انجام شده، تعداد مطالعات آزمایشگاهی صورت گرفته در فشار بالا بسیار محدود می‌باشد. در این مقاله، اثر فشار و غلظت جامد بر روی ماندگی کلی گاز با استفاده از آزمایش اختلاف فشار بررسی شده است. آزمایش‌های انجام شده در این مطالعه با استفاده از گازهای نیتروژن و هوا، سیال پارافین و سیلیس به عنوان جامد در یک ستون راکتوری به قطر cm 16 و ارتفاع m 8/2 انجام گرفته است. محدوده فشار مطالعه شده در این تحقیق بین Bar ا7-18 است. مشاهده شد که افزایش فشار عملیاتی، موجب افزایش ماندگی کلی افزوده می‌شود. همچنین شدت اثر افزایش فشار بر روی ماندگی کلی گاز با افزایش غلظت جامد کاهش می‌یابد. در نهایت، معادله‌ای جهت برآورد ماندگی کلی گاز برای فشارهای بالا بر حسب چگالی گاز (ρg)، سرعت ظاهری گاز (Ug)، چگالی دوغاب (ρSL)، ویسکوزیته دوغاب (μSL) و کشش سطحی مایع (σL) ارائه شد.

کلیدواژه‌ها

عنوان مقاله [English]

Investigating the Effect of Pressure on Gas Holdup of Bubble and Slurry Bubble Columns

نویسندگان [English]

  • Mohammadreza Alaei
  • Mohammad Irani
  • Ali Nakhaeipour
Gas Research Division, Research Institute of Petroleum Industries
چکیده [English]

Bubble and slurry bubble column reactors usually work under pressures beyond the atmosphere in the industries. Although many studies have been done about bubble and slurry bubble column reactors, experimental studies under elevated pressure are very limited. In this study, the effects of pressure and slurry concentration on the gas holdup have been investigated by using pressure difference tests. The experiments of this study are made under pressures up to 18 bar and paraffin and silica are used as the liquid and solid contents. Increasing the operation pressure leads to an increase in gas holdup. It is also found out that the effect of pressure is vanished by increasing the slurry concentration. The experiments are performed in a column with a diameter of 16 cm and a height of 2.8 m. The gases used are nitrogen and air. Finally, a new experimental correlation is developed as a function of gas density (ρg), superficial velocity of gas (Ug), slurry density (ρSL), slurry viscosity (μSL), and liquid surface tension (σL); the correlation is obtained by using the data extracted from this investigation and is in good agreement with the experimental data.

کلیدواژه‌ها [English]

  • Bubble Column Reactor
  • Slurry Bubble Column Reactor
  • Gas Holdup
  • Elevated Pressure
  • Experimental Correlation

مراجع

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پژوهش نفت
دوره 22، شماره 71 - شماره پیاپی 71
مهر و آبان 1391
صفحه 43-56

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