The Effect Of Asphaltic Materials On The Viscosity And Non-Newtonian Behavior Of Crude Oil

Publication Rights Reserved This paper is to be presented at the 32nd Annual California Regional Meeting of the Society of Petroleum Engineers of the American Institute of Mining, Metallurgical and Petroleum Engineers in Bakersfield, November 2–3, 1961, and is considered the property of the Society of Petroleum Engineers Permission to publish is hereby restricted to an abstract of not more than 300 words, with no illustrations, unless the paper is specifically released to the press by the Editor of the Journal of Petroleum Technology or the Executive Secretary. Such an abstract should contain conspicuous acknowledgment of where and by whom the paper is presented. Publication elsewhere after publication in Journal of Petroleum Technology is granted on request, provided proper credit is given that publication and original presentation of the paper. Discussion of this paper is invited. Three copies of any discussion should be sent to the Society of Petroleum Engineers office, and no Discussion should exceed ten percent of the manuscript which it discusses. Such discussions may be presented at the above meeting and be considered for publication in Journal of Petroleum Technology with the paper. Asphaltic materials play a very important role in controlling the viscous behavior of crude oil. This has been revealed by a series of rheological studies on five California crude oils ranging in gravity from 150 to 250 API. The asphaltene contents of these oils range from 4% to 21% by weight. Detailed measurements of viscosity have been carried out at atmospheric pressure at temperatures ranging from 250 to 60 deg. C (77 deg. to 140 deg. F) using a Ferranti cone-plate viscometer. Oil viscosities have been studied at shear rates to 2000 sec. Although crude oils are generally considered to be Newtonian fluids, the asphaltic oils of this investigation exhibit pronounced pseudoplastic, non-Newtonian behavior.