تشکیل هیدرات متان در شرایط ملایم‌تر با استفاده از تسهیل‌کننده‌های ترمودینامیکی

نوع مقاله: مقاله پژوهشی

چکیده

فشار بالای تشکیل هیدرات‌های گازی مهمترین عامل منفی در تولید انبوه هیدرات برای ذخیره‌سازی و انتقال گاز می‌باشد. در این مقاله جهت تشکیل هیدرات در فشار پایین‌تر، اثر دو ماده، تتراهیدروفوران و تتراهیدروپیران در غلظت‌های متفاوت بر نمودار تعادلی تشکیل هیدرات متان بررسی شد. چهار محلول آبی با غلظت‌های 1، 5/2 و 6 درصد مولی از تتراهیدروفوران و 6 درصد مولی از تتراهیدروپیران تهیه و نمودار تعادلی تشکیل هیدرات متان در آن رسم شد. نتایج مشخص نمود که با استفاده از این مواد، هیدرات متان در شرایط بسیار مناسب‌تری از دما و فشار تشکیل می‌شود. در حالیکه فشار تعادلی تشکیل هیدرات متان در دمای 293 درجه کلوین حدود MPa 34 است، با افزودن ماده تتراهیدروفوران با غلظت 5/2 درصد مولی این فشار به حدود MPa 49/2 کاهش یافت که 6/92 درصد کاهش را نشان می‌دهد. همچنین در فشار MPa 5 دمای تعادلی هیدرات متان حدود 278 درجه کلوین است درحالی که در همین فشار دمای تعادل فازی محلول 6 درصد مولی تتراهیدروفوران حدود 306 درجه کلوین بود.

کلیدواژه‌ها


عنوان مقاله [English]

Formation of Methane Hydrate under Milder Conditions Using Suitable Thermodynamic Promoters

چکیده [English]

High formation pressure is the most critical problem hindering formation of gas hydrates in industrial scale for storage and transportation of natural gas. The effects of tetrahydrofuran (THF) and tetrahydropyran (THP) on the phase equilibrium of methane hydrate have been studied. The addition of THF at different concentrations of 1, 2.5 and 6 mol % and THP at 6 mol % aqueous solutions caused hydrate equilibrium pressure to drastically reduce at a specified temperature. While the equilibrium pressure of methane hydrate is about 34 MPa at 293K, this equilibrium pressure decreased to about 2.5 MPa using 2.5 mol % of THF. Furthermore, the hydrate equilibrium temperature greatly increased at a specified pressure. The equilibrium temperature of methane hydrate at 5 MPa is about 278K. This equilibrium temperature increased to about 306K using 6 mol % of THF.

کلیدواژه‌ها [English]

  • Gas Hydrate
  • Phase Equilibrium
  • Thermodynamic Promoter
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