Rheological Behavior of Waxy Crude Oils under Oscillatory Shear and Effect of Plant Seed Oil
|International Journal of Engineering Trends and Technology (IJETT)||
|© 2018 by IJETT Journal|
|Year of Publication : 2018|
|Authors : Adam M Giri, Ali A. Rabah
|DOI : 10.14445/22315381/IJETT-V58P231|
Adam M Giri, Ali A. Rabah"Rheological Behavior of Waxy Crude Oils under Oscillatory Shear and Effect of Plant Seed Oil", International Journal of Engineering Trends and Technology (IJETT), V58(4),165-176 April 2018. ISSN:2231-5381. www.ijettjournal.org. published by seventh sense research group
Different samples of waxy crude oils were taken before pipeline inlet to field processing facility in the Hadida and Heglig crude pipelines which carrying crude oil from producing oil fields located in the west part of the west Kordofan state, to the costal terminal at Port Sudan. Samples were tested for their flow behavior under superimposed small amplitude oscillatory by dynamic rheometer. The oscillation behavior of the crude oils is measured under dynamic rheological tests for the following parameters: strain sweep, frequency sweep and temperature sweep tests. However, strain sweep was first performed at frequency 10 rad/sec and temperature of 50oC (below wax appearance temperature) to determine linear viscoelastic region. Further, the linear viscoelastic region was calculated as (0.05%) which is used to carry out frequency sweep and temperature sweep tests. . Moreover, untreated and additive treated crudes with flow improvers (Jatropha Curcas seed oil and Xylene) were used to identify the impact of additives on pour point, wax appearance temperature and flow properties of the crudes. GC-FID was introduced to perform a composition analysis for untreated and additive treated crudes and average carbon number distribution was identified as C26. In addition, untreated and additive treated crudes were thermal fractionated and their wax appearance temperatures were measured by DSC and the results compared with those obtained from viscometry method. Further, the two crudes show high pour point (33 oC and 33 oC) and high wax appearance temperature (59.88 oC and 59 oC) for Hadida and Heglig crudes respectively, which is essentially required treatment for their storage, production and transportation via pipeline. Moreover, it was observed that concentration of 5%v/v Jatropha seed oil and xylene capable to reduce Heglig crude pour point from (33 oC to 15 and 18 oC) respectively, on the other hand all pour point depressant used in this study were failed to affect the pour point of Hadida crude, but they affect its viscosity and show improvement in the flow behavior. However, Hadida and Heglig crudes exhibit a negligible amount of asphaltenes content (0.05) and there may be no problems for the crudes rheology with asphaltenes precipitation. Furthermore, measured rheological parameters such as storage modulus (G`) and loss modulus (G") reveals that, the two crudes exhibit viscoelastic behavior where at low frequencies storage modulus dominate loss modulus indicating solid-like behavior and at high frequencies loss modulus dominate storage modulus indicating liquid-like behavior, also gelling behavior of the crudes was determined by crossover point at which the G` value overlap the G" value and this behavior was confirmed by low tan ? values (i.e. less than one as indicated in Table 4). Furthermore, vegetable seed oil obtained from plant sources such as Jatropha Curcas seed oil could be used as flow improvers for pour point depressant and enhances flow properties of Sudanese waxy crude oils.
 C. Chang, Nguyen, Q.D. and Ronningsen, H.P. "Isothermal start-up of pipeline transporting waxy crude oil", Journal of Non-Newtonian Fluid Mechanics, 87: 127-154, 1999.
 J.A. Ajienka, and C.U. Ikoku, "the effect of temperature on the Rheology of waxy crude oils", Society of Petroleum Engineers SPE, P.23605, 1991.
 L. Dong, H. Xie and F.Zhang, "Chemical control techniques for the paraffin and Asphaltene deposition", SPE 65380, Presented at the 2001 SPE International Symposium on Oilfield Chemistry (Houston, Feb., 13-16).
 J. P. Buzen and G. Potter "selection and operation of production facilities for handling high pour point crude oil", Paper SPE 17627, presented at SPE International Meeting on Petroleum Engineering, held in Tianjin, China, November 1-4, 1988.
 D. C. Thomas "selection of paraffin control products and applications", Paper SPE 17627, presented at SPE International Meeting on Petroleum Engineering, held in Tianjin, China, November 1-4, 1988.
 G. McClaflim and D. J. Whitfill "control of paraffin deposition in production operations", J Petrol. Tech. (November, 1984), SPE 12204, 1965.
 A. Hunt, "Uncertainties remain in predicting paraffin deposition", Oil & Gas J. 7(29):96-103, 1996.
 M. G. Bemadiner, "Advanced asphaltenes and paraffin control technology", SPE paper No.25192 presented at the Int. Symp. On Oilfield Chem. New Orleans, LA; March, 2-5, 1993.
 K.A. Ferworn, A. Hummami, H. Ellis "Control of wax deposition: an experimental investigation of crystal morphology and an evaluation of various chemical solvents", SPE paper No. 37240 presented at the Int. Symp. On Oilfield chemical. Houston, TX, February, 18-21, 1997.
 M. D. C. Garcia, L. Carbognani, M. Orea and A. Urbina "The influence of alkane class-type on crude oil wax crystallization and inhibitor efficiency" , Journal of Petroleum Science and Engineering, vol.25 (9 & 10):99, 2000.
 C. E. Jr. Reistle "paraffin and congealing oil problems", Bull, USBM, No.348, vol. 125, 1932. K.M. Barker and M. E. Newberry" oil field paraffin control manual", Petrolite Corporation, 1988.
 G. E. Addison "Paraffin control more cost effective", Society of Petroleum Engineering Paper, 13391, p. 203-210, 1984.
 G. W. Gilby in "Chemicals in the oil Industry" Royal Society of Chemistry, London, p.108,1983.
 B. Smith in "Encyclopedia of Chemical Processing and Design" (Ed. J.J. Mcketta) Marcel Dekker Inc. New York, USA. Vol. 22, p. 261, 1985.
 E.D Burger; Perkins, T.K. and Striegler, J.H. "Studies of wax deposition in the Trans-Alaska Pipeline". Journal of Petroleum Technology, 3: 1075-1086, 1981.
 B.J. Musser, and Kilpatric, P.K., " Molecular characterization of was isolated from a variety of crude oils". Energy and Fuels; 12: 715-725, 1997.
 H.M.,Nermen, and Magdy, T.Z. "Separation of microcrystalline waes from local crude petrolatums using solvent-antisolvent mixtures". Petrol Sci Technol., 11-12:15553-15569, 2004.
 A.M.Elsharkawy; Al-Sahhaf, T.A.; Fanhim, M.A. "Wax depositionfrom Middle East Crudes". Fuel, , 79: 1047-1055, 1999.
 J.Hanoo; Gupta, A.K., and Agrawal, K.M. "Characterization of total waes derived from some Indian crude oils by fractionation", Petrol Sci Technol, 15: 237-356, 1997.
 Rai et al. " Multiphase transpiration of high waxy crudes". SPE Advance Technology Services 4(1), 178, 1995.
 E. F. Lucus, C. X. Silva, and D. R. S. Alvares "New additives for the pour point reduction of petroleum middle distillates". Energy and Fuels, Vol. 18(3), p. 599-604, 2004.
 M. Kane`; Djabourov, M.; Volle,J.; Lechairec, J. and Frebourg, G. "Morphology of paraffin crystals in waxy crude oils cooled in quiescent conditions and under flow", Fuel, 82: 127-135, 2003.
 A. Aiyeijani, D. P. Chakrabarti, A. Pilgrim and M. Sastry "Wax formation in oil pipelines: A critical review" . International Journal of Multiphase Flow, 37 (7), 671-694, 2011.
 Monger-McClure et. al. "Comparison of cloud point measurement and paraffin prediction method", SPE Prod. & Facilities, 14(1), 4, 1999.
 H.P. Ronningsen, B.Bjorndal, A.B.Hansen and W.B.Pedersen "Wax precipitation from North Sea crude oils.1. "Crystallization and dissolution temperature, and Newtonian and non-Newtonian flow properties". Energy Fuels; 5:895-908, 1991.
 K. M Agarwal, R. C. Purohit, and M. Surianarayanan, G. C. Joshi and R. Krishna, "Influence of waxes on flow properties of Bomby high crude", Fuel & Gas 68, 937-939, 1989.
 K. M Agarwal, R. C. Purohit, and G. C. Joshi"Rheological properties of Bomby high crude oil in relation to its n-alkane components", Fuel Sci. Technol. Intl. 12, 1245-1256, 1994.
 T. S. Brown, V.G. Nielsen and D.D. Erickson " the effects of light ends and high pressure on paraffin formation", SPE Paper 28505, 1994nAnnual Tech. conf. Society of Petroleum Engineers, New Orleans, L.A. September 25-28.
 A.A. Abdelwaly, "New correlation estimates viscosity of paraffinic stocks", Oil & Gas J. 95(26), 61-65, 1997.
 D.S Lakshmi, R.C. Purohit, S.P. Srivastava, S.P. Hautiyal, G.B. Tiwari, M. Krishna, M.V. Rao and M.B. Rao "Low temperature flow characteristics of some waxy crude oils in relation to their composition part-2", Effect of wax composition of the dewaxed crude oils with/and without additives", Petrol. Sci. Technol. 15, 685-697, 1997.
 P.A. Olusegun, D.U. Joseph, E.E. Vincet, and A.A. Ayodeji "A study on the use of plant seed oils, triethanolamine and xylene as flow improvers of Nigerian waxy crude oil", Journal of Applied Research and Technology, vol. 14, Issue 3, p. 195-205, June 2016.
 R.Venkatessan, Ostlund, J,A.;Chawla,H.;Wattana,P. Nyden, and Fogler, H.S, "The effect of asphaltenes on the gelation of waxy oils" , Energy and Fuels, 17, 1630-1640, 2003.
 K.S. Wang, Wu, C.H.; Creek, J.I; Shuler, P.J. and Tang, Y. "Evaluation of effects of selected wax inhibitors on paraffin deposition", Petrolam Science and Technology. 21, 369-379, 2003.
 J.Wang, Brower, K. and Buckley, J. "Advances in observation of asphaltenes destabilization", Proceeding of SPE on Oil Field Chemistry, Houston, Texas. February 16-19,SPE paper 50745. 1999.
 P.S. Hemant, Kiranabala, A. and Bharambe, D. P. "Performance based designing of wax crystal growth inhibitor". Energy and Fuels, 22(6), 3930-3938. , 2008.
 A. A. Hafiz, and T.T. Khider, "Hexa-Triethanolamine oleate esters as pour point depressants for waxy crude oils", Journal of Petroleum Science and Engineering, 56, 296-302, 2007.
 M.C.K. De Olivera, Teixeira, A.; Vieira, L.C., de Carvalho, R. M.; de Carvalho, A.B.M. and do Couto, B.C."Flow assurance study for waxy crude oils", Energy and Fuels, 26(5), 2688-2695, 2011.
 C.I. Oseghale, Akpabio, E. J.; and Edebor,O."Mitigating potential risk of paraffin wax deposition on oil pipelines in Niger Delta", Journal of Engineering and Applied science, 7(4), 348-352, 2012.
 D.S.Giordani,"Estudo do equilibrio de fases solidos-liquido em sistemas modelo de hidro carbonelos de Alto Peso molecular", Master disert. Engenharia Quimica, FEQ, Unicamp, campinas, pp. 134, 1993.
 D.D.Erickson, , Nielsen V.G., Brown T.T." Measurement and prediction of the kinetics of paraffin deposition", SPE 68th Annual Tech. Conference and Exhibition, SPE 26548 Houston, TX, 1993.
 R.Venkatesan; Singh P.; and Fogler, H.S, "Delineating the pour point and Gelation temperature of waxy crude oils", SPE J. 7(4):349, 2002.
Waxy crude oils, Chemical additive, Jatropha seed oils, Rheology, DSC, Thermal and Oscillatory Behavior