Abstract    Gas hydrates attracted worldwide attention due to their potential as huge energy resource in the recent decades. Effective parameters which influence the formation of hydrates are high pressure, low temperature and water presence. HYSYS software is one of the major simulators which are widely used in the chemical and thermodynamic processes. This research was conducted to simulate gas hydrate formation of Lavan-3 gas well and Salman gas field using the HYSYS software. The steady state simulation of hydrate formation was performed by the Peng-Robinson equation of state. The data were compared with the experimental ones. It was concluded that the HYSYS is able to predict hydrate formation, properly (Average Absolute Error<1). Two novel correlations were also developed to estimate hydrate formation conditions of natural gas.

Keywords    Gas hydrates, HYSYS, Peng-Robinson, Simulation

چکیده    در دهه های گذشته هیدرات های گازی به خاطر پتانسیل بالا در تامین منابع عظیم انرژی توجه جهانی را به خود منعطف کرده اند. عوامل تاثیرگذار بر روی تشکیل هیدرات گازی عبارت اند از: فشار بالا، دمای پایین و حضور آب. نرم افزار هایسیس یکی از بهترین شبیه ساز هایی است که در فرآیند های شیمیایی و ترمودینامیکی مورد استفاده قرار می گیرد. در این تحقیق سعی شده است با استفاده از نرم افزار هایسیس شرایط تشکیل هیدرات گازی در چاه گازی لاوان-3 و همچنین میدان گازی سلمان در شرایط پایا و با استفاده از معادله حالت پنگ رابینسون بررسی گردد. داده های بدست آمده از شبیه سازی با نتایج آزمایشگاهی مورد مقایسه قرار گرفت و خطای بدست آمده کمتر از 1درصد مشاهده شد که نشان از دقت بالای نرم افزار مورد اشاره در بررسی شرایط تشکیل داشت. در پایان دو معادله ی جدید برای پیش بینی شرایط تشکیل هیدرات گازی در گاز طبیعی پیشنهاد شد

References      1.     Sloan Jr, E.D. and Koh, C., "Clathrate hydrates of natural gases, CRC press,  (2007). 2.     Zele, S., Lee, S.-Y. and Holder, G., "A theory of lattice distortion in gas hydrates", The Journal of Physical Chemistry B,  Vol. 103, No. 46, (1999), 10250-10257. 3.     Carroll, J., "Natural gas hydrates: A guide for engineers, Gulf Professional Publishing,  (2009). 4.     Mao, W.L., Mao, H.-k., Goncharov, A.F., Struzhkin, V.V., Guo, Q., Hu, J., Shu, J., Hemley, R.J., Somayazulu, M. and Zhao, Y., "Hydrogen clusters in clathrate hydrate", Science,  Vol. 297, No. 5590, (2002), 2247-2249. 5.     Klauda, J.B. and Sandler, S.I., "Global distribution of methane hydrate in ocean sediment", Energy & Fuels,  Vol. 19, No. 2, (2005), 459-470. 6.     Pooladi-Darvish, M., "Gas production from hydrate reservoirs and its modeling", Journal of Petroleum Technology,  Vol. 56, No. 06, (2004), 65-71. 7.     Moridis, G.J., "Toward production from gas hydrates: Current status, assessment of resources, and simulation-based evaluation of technology and potential", SPE Reservoir Evaluation & Engineering, Vol. 12, (2009), 745–771.. 8.     Ghiasi, M.M., "Initial estimation of hydrate formation temperature of sweet natural gases based on new empirical correlation", Journal of Natural Gas Chemistry,  Vol. 21, No. 5, (2012), 508-512. 9.     Moshfeghian, M., "The pfgc equation of state at the age of fourteen", Pure and Applied Chemistry,  Vol. 61, No. 8, (1989), 1405-1411. 10.   Carson, D.B. and Katz, D.L., "Natural gas hydrates", Transactions of the AIME,  Vol. 146, No. 01, (1942), 150-158. 11.   Van der Waals, J. and Platteeuw, J., "Clathrate solutions", Advances in Chemical Physics, Vol. 2,  (1959), 1-57. 12.   Katz, D.L., "Prediction of conditions for hydrate formation in natural gases", Transactions of the AIME,  Vol. 160, No. 01, (1945), 140-149. 13.   Katz, D., Look ahead in gas storage technology., Univ. of Michigan, Ann Arbor. (1981) 14.   Din, M.M. and Sadeg Zadeh Ahari, J., "Determination of suitable concentrations of H2O and CO2 in the feed of syngas production", International Journal of Engineering,  Vol.16 (2003), 21-28. 15.   Carlson, E.C., "Don't gamble with physical properties for simulations", Chemical Engineering Progress,  Vol. 92, No. 10, (1996), 35-46. 16.   Plus, A., "Aspen plus user guide", Aspen Technology Limited, Cambridge, Massachusetts, United States,  (2003). 17.   Peng, D.-Y. and Robinson, D.B., "A new two-constant equation of state", Industrial & Engineering Chemistry Fundamentals,  Vol. 15, No. 1, (1976), 59-64. 18.   Hill, A.E. and Malisoff, W.M., "The mutual solubility of liquids. Iii. The mutual solubility of phenol and water. Iv. The mutual solubility of normal butyl alcohol and water", Journal of the American Chemical Society,  Vol. 48, No. 4, (1926), 918-927. 19.   Panish, M. and Ilegems, M., "Phase equilibria in ternary iii–v systems", Progress in Solid State Chemistry,  Vol. 7, No., (1972), 39-83.