The Effect of Linear and Branched Inhibitors on Asphaltene Precipitation in Crude Oil Using the Viscometric Method

Document Type : Research Paper

Authors

Faculty Of Chemical Engineering, Tarbiat Modares University, Tehran, Iran

Abstract

One of the main problems in production of oil reservoirs is the formation of asphaltene precipitation. Blockage in porous medium, wells, and facilities has a detrimental effect on the production of asphaltenic oil. Generally, asphaltenes are heaviest and most polar fractions that can be found in crude oil. These compositions have a complex molecular structure which are series of non-hydrocarbon molecules and soluble in benzene and insoluble in normal alkanes and solvents with low molecular mass. Based on recent experiments have been supposed that these compositions can be partially solved in oils at colloidal state. The nature and behavior of asphaltene in crude oils is complex so changes in temperature, pressure and composition of crude oils during production can result in precipitation of asphaltene components. These parameters affect the chemical equilibrium in reservoirs and result precipitation. A possible way to prevent of asphaltene precipitation is by adding an asphaltene stabilizer, i.e. inhibitor. Asphaltene inhibitors act in a way similar to resins, peptizing the asphaltenes and keeping them in solution. The inhibitor efficiency depends on its chemical and structural characteristics, largely. However, the inhibitor ability to stabilize asphaltenes depends also on the solvent or dispersion medium. The main objective of this research is to investigate the effect of three different inhibitors on asphaltenes deposition using viscometric method.The results show decrease in length of hydrocarbonic chains because of branches and steric hindrance between methyl groups will decrease inhibition strength of branched DBSA compare to linear DBSA.
 

Keywords

References

pp. 249–298, 1994.
T.F., Chilingarian,G.V. (Eds.), Asphaltene and Asphalts, 1. Elsevier Science B.V.,Amsterdam, The Netherlands,
[3]. Kokal S. L. & Sayegh S. G., “Asphaltenes: The Cholesterol Of Petroleum”. SPE 29787, Middle East Oil Show, 11-14 March, Bahrain, 1995.
[4]. Leontaritis K. J. & Mansoori G. A., “Asphaltene Flocculation During Oil Production and Processing: A Thermodynamic Collodial Model”, SPE International Symposium on Oilfield Chemistry, 4-6 February 1987, San Antonio, Texas.
[5]. Yadollah M., Martin G. C, Zhang X. and Shaw J. M., “Asphaltene phase behavior: prediction at a crossroads”, Fluid Phase Equilibria,Vol. 228-229 , pp. 21–26, 2005.
[6]. Mullins O. C, Sheu E. Y, Hammami A. and Marshall A. G., Asphaltenes, Heavy Oils, and Petroleomics, NY: Springer ,New York, 2007.
[7]. Ramos A. C. S., Asfaltenos em petroleos brasileiros : agregação em solventes aromaticos, desenvolvimento de aditivos e estabilização de emulsões, Campinas, 275p. Tese (Doutorado) -Faculdade de Engenharia Quı´mica. Universidade Estadual de Campinas, 2001.
[8]. Al Sahhaf T. A., Fahim M. A., & Elkilani, A. S., “Retardation of Asphaltene Precipitation by Addition of Toluene, Resins, deasphalted oil and surfactant”, Fluid Phase Equilibria, pp. 194-197, 1045-1057, 2002.
[9]. Gonzalez G. and Middea A., “Peptization of asphaltene by various oil soluble amphiphiles”, Colloids and Surfaces ,Vol. 52, pp. 207-217, 1991.
[10]. Chang C. L. and Fogler H. S., “Stabilization of Asphaltenes in Aliphatic Solvents Using Alkylbezene-Derived Amphiphiles: 1. Effect of the Chemical Structure of Amphiphiles on Asphaltene Stabilization”, Langmuir, Vol. 10, pp. 1749-1757, 1994a.
[11]. Chang C. L. and Fogler H. S., “Stabilization of Asphaltenes in Aliphatic Solvents Using Alkylbenzene-Derived Amphiphiles. 2. Study of theAsphaltene-Amphiphile Interactions and Structures Using Fourier Transform Infrared Spectroscopy and Small-Angle X-ray Scattering Techniques”, Langmuir, Vol. 10, pp. 1749-1757, 1994b.
[12]. Rocha Junior L. C., Ferreira M. S. and da Silva Ramos A. C., “Inhibition of asphaltene precipitation in Brazilian crude oils using new oil soluble amphiphiles”, J. Pet. Sci.Eng, Vol. 51, pp. 26-36, 2006.
[13]. Boukherissa M., Mutelet F., Modarressi A, Dicko A., Dafri D. and Rogalski M., “Ionic Liquids as Dispersants of Petroleum Asphaltenes”, Energy & Fuels, Vol. 23, pp. 2557–2564, 2009.
[14]. Ghloum E. F., Al-Qahtani M. and Al-Rashid A., “Effect of inhibitors on asphaltene precipitation for Marrat Kuwaiti reservoirs”, J. Pet. Sci.Eng, Vol. 70, pp.99-106, 2010.
[15]. Mohammadi M., Akbari M., Fakhroueian Z., Bahramian A., Azin R. and Arya SH., “Inhibition of Asphaltene Precipitation by, Tio2, Sio2 and ZrO2 Nanofluids”, Energy & Fuels, Vol. 25, pp. 3150–3156, 2011.
[16]. Escobedo J. and Mansoori G. A., “Theory of viscosity as a criterion for determination of onset of asphaltene flocculation”, SPE 28729, Texas, 20–26 Aug. 1996.
[17]. Mousavi-Dehghani S. A., Riazi M. R., Vafaie-Sefti M. and Mansoori G. A., “An analysis of methods for determination of onsets of asphaltene phase separations”, J. Petrol. Sci. Eng., Vol. 42, pp. 145–156, 2004.
[18] Wu J., Prausnitz J. M. and Firoozabadi A., “Molecular thermodynamics of asphaltene precipitation in reservoir fluids”, AIChEJ, Vol. 44(1), pp. 197-209, 2000.
Journal of Petroleum Research
Volume 23, Issue 75 - Serial Number 75
November and December 2013
Pages 30-39

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