1070-4272/05/7803-0500+2005 Pleiades Publishing, Inc.
Russian Journal of Applied Chemistry, Vol. 78, No. 3, 2005, pp. 500!505. Translated from Zhurnal Prikladnoi Khimii, Vol. 78, No. 3,
2005, pp. 506!511.
Original Russian Text Copyright + 2005 by Myagchenkov, Chichkanov, Yakovenko.
OF FOSSIL FUEL
Toms Effect in Direct Crude Oil Emulsions as Influenced
by the Stream Velocity and Concentration of Anionic
Copolymers of Acrylamide
V. A. Myagchenkov, S. V. Chichkanov, and D. F. Yakovenko
Kazan State Technological University, Kazan, Tatarstan, Russia
Received June 2, 2004; in final form, December 2004
Abstract-The major relationships in the Toms effect in direct crude oil emulsions differing in the dispersed
phase concentration were studied on a modified turbulent rheometer with anionic copolymer of acrylamide as
the polymer additive. The Toms effect was studied as influenced by the polymeric additive concentration
and shear stress.
One of the most important and urgent problems
currently faced by the oil extraction industry is devel-
opment of efficient, scientifically sound power-saving
technologies accelerating high-speed pipeline trans-
portation of hydrocarbon raw materials [1, 2]. Unlike
laboratory experiments, real processes yield a water-
rich end product, which creates additional problems.
In view of the fact that the water enrichment of the
extracted crude oil tends to increase with increasing
time of exploitation of wells , this necessitates a
search for new methods of intensifying the transporta-
tion of hydrocarbon raw materials. This concerns not
only dehydrated but also water-enriched oil-containing
dispersed systems with a complex composition, above
all, direct (oil-in-water) and reverse (water-in-oil)
emulsions [4, 5].
In this situation, much promise is offered by poly-
meric additives (PAs) introduced into the dispersion
medium in minor amounts in order to reduce the
hydraulic resistance in turbulent streams of disperse
systems (Toms effect). The Toms effect was most
successfully applied to dehydrated oil [6, 7]. Good
performance of PAs can be illustrated by the results of
the tests on the 125-km long Tikhoretsk3Novorossiisk
main crude oil pipeline with the internal diameter of
the pipe of 0.8 m . With nonpolar high-molecular-
weight polyhexene in the concentration of 8 g cm
additive, the oil transportation was considerably ac-
celerated owing to a 20% decrease in the friction loss.
Good performance of polyolefin-based nonpolar
polymeric additives as turbulence [quenchers] in oil
streams was also confirmed by experiments on pump-
ing dehydrated oil through the Aleksandrovskoe3
Anzhero3Sudzhensk main pipeline (oil density
850 kg m
; kinematic viscosity 5010
Reynolds number Re = 3.5010
at shear stress of
3 Pa) .
The promise of ionic and nonionic water-soluble
(co)polymers for decreasing the hydrodynamic resist-
ance in oil-containing disperse systems is understood
to a much lesser extent. There are only fragmentary
data confirming the suitability for this purpose of
water-soluble polymer additives  whose essential
properties need to be characterized more precisely
. At the same time, development of technologies
of high-speed transportation of oil streams using
water-soluble PAs is well justified: They showed the
best performance in development and application of
industrial technologies intensifying high-speed trans-
portation of water streams [12, 13].
Here, we continue our previous studies  by
quantitatively analyzing the Toms effect as influenced
by the concentration of water-soluble PAs (anionic
copolymers of acrylamide) and by the velocity of the
turbulent streams of direct oil emulsions.
Crude oil from Novosheshminsk site (Tatarstan)
served as the main component of the dispersed phase
of the emulsions. At 20oC, the oil had the kinematic
viscosity n = 210010
and density r
910 kg m
. The viscosity of oil was decreased by
preliminary dilution with kerosene [Volgograd Refin-