شناسایی رژیم‌های جریان دو فازی و محاسبه افت فشار در چاه‌های تحت فرازآوری با گاز

نوع مقاله: مقاله پژوهشی

نویسندگان

1 دانشگاه علم و صنعت ایران، دانشکده مهندسی شیمی، آزمایشگاه تحقیقاتی شبیه‌سازی و کنترل فرایندها،

2 دانشگاه صنعتی شریف، دانشکده مهندسی شیمی و نفت

چکیده

در بسیاری از مخازن نفتی که به علت گذشت زمان طولانی از شروع برداشت مخزن قادر به تولید طبیعی نمی‌باشند، از فرایند فرازآوری پیوسته با گاز برای افزایش تولید استفاده می‌گردد. در این تحقیق، محاسبات افت فشار جریان دو فازی در چاه تحت فرازآوری که پیچیده‌ترین و زمان برترین بخش مدل‌سازی این فرایند است، با استفاده از نقشه جریان و روابط مکانیستیک صورت گرفت. استفاده از توصیف دو جزئی نفت- سیاه به‌دلیل منظور نکردن تغییرات ترکیب سیال و ثابت گرفتن فشار حباب در طی عبور سـیال در چاه، خطای قابل توجهی در محاسبات افت فشار ایجاد می‌کند. بنابراین، برای توصیف دقیق و سریع رفتار ترمودینامیکی سیال هیدروکربنی جاری در فرایند، از توصیف چند جزئی با به‌کارگیری روش پارامترهای کاهش یافته استفاده شد. نتایج نشان می‌دهد که استفاده از روابط تجربی در مدل‌سازی چاه تحت فرازآوری با گاز، باعث خطای قابل توجهی در محاسبات می‌شود. زیرا در روش‌های تجربی، روابط مناسبی برای گذر از الگوهای جریان به یکدیگر وجود ندارد و گرادیان فشار در این مرزها دچار گسستگی می‌شود.

کلیدواژه‌ها


عنوان مقاله [English]

Identification of Two-Phase Flow Regimes and Computation of Two Phase Pressure Drop in Gas Lifted Wells

نویسندگان [English]

  • Mehrak Mahmudi 1
  • M.T. Sadeghi 1
  • F.A. Farhadpour 2
1 Process Simulation and Control Research Lab., Department of Chemical Engineering, Iran University of Science and Technology, Tehran, Iran
2 Department of Chemical and Petroleum Engineering, Sharif University of Technology, Azadi Ave., Tehran, Iran
چکیده [English]

Continuous gas lift process is used to boost oil production in many mature reservoirs, which can no longer produce under natural drive. In this article, application of mechanistic flow maps as well as the correlations estimating pressure drop in a gas lifted well, as the most complex and time consuming part of the gas lift modeling is examined. Using the black-oil model to compute the two-phase pressure drop in a gas lifted well leads to a substantial error due to the changes in composition and bubble point pressure along the well. In order to describe the thermodynamic behavior of the hydrocarbon fluid, a multi-component compositional description has been applied using the reduced parameter method. The results show that the empirical maps and correlations lead to severe discontinuities at transition points between the different flow regimes. This causes an unacceptable error when computing the pressure drop.

کلیدواژه‌ها [English]

  • Two-Phase Flow
  • Pressure Drop
  • Flow regime
  • Gas Lift Process
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