مدل‌سازی ترمودینامیکی تشکیل هیدرات هیدروژن سولفید در حضور ممانعت کننده‌ها

نوع مقاله : مقاله پژوهشی

نویسندگان

پژوهشکده چرخه سوخت هسته‌ای، پژوهشگاه علوم و فنون هسته‌ای، تهران، ایران

چکیده

 در این تحقیق تشکیل هیدرات هیدروژن سولفید در حضور ممانعت کننده‌های ترمودینامیکی مدل شده است. مدل ترمودینامیکی پیشنهادی برای پیش‌بینی فشار تعادلی تشکیل هیدرات هیدروژن سولفید در آب خالص و همچنین در حضور سه نمک                                                                                            NaCl، KCl و CaCl2، دو الکل متانول و اتانول و اتیلن گلایکول به کار برده شد. برای به دست آوردن ضریب فعالیت آب در محلول‌های مورد نظر معادلهExtended-UNIQUACا(E-UNIQUAC)مورد استفاده قرار گرفت. پارامترهای ساختاری معادله مورد نظر از مقالات استخراج شد، ولی پارامترهای برهم‌کنش بین مولکولی در مدل E-UNIQUAC از طریق برازش داده‌های تجربی با مدل پیشنهادی به دست آمد. پس از محاسبه این پارامترها، از آنها برای پیش‌بینی فشار تعادلی تشکیل هیدرات هیدروژن سولفید در حضور الکترولیت‌ها (NaClا،،KClو CaCl2)، الکل‌ها (متانول و اتانول) و اتیلن گلایکول استفاده شد. نتایج حاصل از این مدل توافق بسیار خوبی با داده‌های تجربی دارد و میزان انحراف میانگین مدل و داده‌های تجربی 82/3 % است.
 

کلیدواژه‌ها


عنوان مقاله [English]

Thermodynamic Modeling of Hydrogen Sulfide Hydrate Formation in the Presence of Inhibitors

نویسندگان [English]

  • Alireza Keshtkar
  • Abolfazl Mohammadi
Atomic Energy Organization of Iran, Tehran, Iran
چکیده [English]

The hydrate formation of hydrogen sulfide in the presence of thermodynamic inhibitors has been modeled in this study. A thermodynamic model has been employed for predicting the hydrate formation of the following systems: H2S + Water + Salts (NaCl, KCl, and CaCl2), H2S + Water + Alcohols (methanol and ethanol), and H2S + Water + ethylene glycol. The extended-UNIQUAC (E- UNIQUAC) model has been used for predicting the activity coefficient of water in the liquid phase. The structural parameters of E-UNIQUAC model have been extracted from literature but the interaction parameters of this model have been obtained by fitting the model with the experimental data. The results of the developed model show good agreement with the experimental data and the absolute average deviation of the model from experimental data is 3.82%.

کلیدواژه‌ها [English]

  • Gas Hydrate
  • Hydrogen Sulfide
  • Thermodynamic Inhibitors
  • Thermodynamic Modeling
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