Download - Petroleum 2012.pdf
7/21/2019 Petroleum 2012.pdf
http://slidepdf.com/reader/full/petroleum-2012pdf 1/7
See discussions, stats, and author profiles for this publication at: http://www.researchgate.net/publication/230775665
Pipeline transportation of viscous crudes asconcentrated oil-in-water emulsions
ARTICLE in JOURNAL OF PETROLEUM SCIENCE AND ENGINEERING · APRIL 2012
Impact Factor: 1.42 · DOI: 10.1016/j.petrol.2012.04.025
CITATIONS
17
READS
647
4 AUTHORS, INCLUDING:
Abdurahman Nour
Universiti Malaysia Pahang
135 PUBLICATIONS 212 CITATIONS
SEE PROFILE
Azhari Hamid Nour
Universiti Malaysia Pahang
132 PUBLICATIONS 108 CITATIONS
SEE PROFILE
HAYDER A. ABDULBARI
Universiti Malaysia Pahang
82 PUBLICATIONS 57 CITATIONS
SEE PROFILE
All in-text references underlined in blue are linked to publications on ResearchGate,
letting you access and read them immediately.
Available from: Abdurahman Nour
Retrieved on: 14 November 2015
7/21/2019 Petroleum 2012.pdf
http://slidepdf.com/reader/full/petroleum-2012pdf 2/7
Pipeline transportation of viscous crudes as concentrated
oil-in-water emulsions
N.H. Abdurahman a,n, Y.M. Rosli a, N.H. Azhari b, B.A. Hayder a
a Faculty of Chemical and Natural Resources Engineering, University Malaysia Pahang (UMP), Malaysiab Faculty of Industrial Sciences and Technology, University Malaysia Pahang (UMP), Malaysia
a r t i c l e i n f o
Article history:
Received 24 February 2011Accepted 30 April 2012Available online 15 May 2012
Keywords:
pipeline
viscosity
stability
oil-in-water emulsions
heavy crude oil
a b s t r a c t
Stable concentrated oil-in-water (O/W) emulsions were prepared and their application for heavy oil
pipeline transportation was investigated using very viscous Malaysian heavy crude oil. Two Malaysianheavy crude oil samples, Tapis and a blend of Tapis and Masilla, were used to produce heavy crude oil-
in-water emulsions. The diverse factors affecting the properties and stability of emulsions were
investigated. There was a restricted limit of 68 vol% and 72 vol% for crude oil content in the emulsions,
and beyond that limit, the emulsion underwent phase inversion. The study revealed that the stability of
the oil-in-water emulsion stabilized by Triton X-100 increases as the surfactant concentration
increases, with a subsequent decrease in the crude oil–water interfacial tension (IFT). Increasing the
oil content, the speed and duration of mixing, the salt concentration and the pH of the aqueous phase of
the emulsion resulted in increased emulsion stability, while increases in the temperature of the
homogenization process substantially reduced the viscosity of the prepared emulsions. Fresh water and
synthetic formation water were used to study the effect of aqueous phase salinity on the stability and
viscosity of the emulsion. The results showed that it was possible to form stable emulsions with
synthetic formation water characterized by a low dynamic shear viscosity.
& 2012 Elsevier B.V. All rights reserved.
1. Introduction
With the combination of an increase in world energy demand
and the decline of conventional oils, heavy crude oils have been
presented as a relevant hydrocarbons resource for use in the
future (Lanier, 1998). Hydrocarbon resources are very important
given that they account for approximately 65% of the world’s
overall energy resources (Langevin et al., 2004). Currently, crude
oil is the most important hydrocarbon resource in the world, and
heavy crudes account for a large fraction of the world’s potentially
recoverable oil reserves (Chilingar and Yen, 1980; Langevin et al.,
2004). However, heavy crude oils only account for a small portion
of the world’s oil production because of their high viscosities,which cause problems in the transportation of these oils via
pipelines (Plegue et al., 1989). Historically, demand for heavy and
extra-heavy oil has been marginal because of their high viscosity
and composition complexity that make them difficult and expen-
sive to produce, transport and refine. Nowadays, Alberta in
Canada and Orinoco Belt in Venezuela are good examples of
regions producing extra heavy oil. However, an increase in
production of heavy and extra crude oil will take place in several
regions like the Gulf of Mexico and Northeastern China, as it will
be needed over the next two decades to replace the declining
production of conventional middle and light oil. The production of
heavy crudes is expected to increase significantly in the near
future as low viscosity crudes are depleted (Plegue et al., 1989).
Currently, there are three general approaches for transportation
of heavy and extra heavy oil: viscosity reduction, drag minimiza-
tion and in-situ oil upgrading (Rafael et al., 2011). Several special
nonconventional methods for the transport of heavy oil have been
proposed, and they include preheating of the crude oil with
subsequent pipeline heating (Layrisse, 1998; Saniere et al.,
2004), dilution with lighter crude oils (Iona, 1978), partial
upgrading (MacWilliams and Eadie, 1993) and injection of awater sheath around the viscous crude. Each of these methods
has logistic, technical or economic drawbacks.
Although it is often mentioned that the field of hydroproces-
sing catalysis is mature and there are not much compasses for
researcher, the increasing demand of heavy oil has made hydro-
processing a challenging task for refiners as well as for research-
ers (Rana et al., 2007). Paraffin wax deposition costs the oil
industry billions of dollars worldwide for prevention and reme-
diation. Paraffin precipitation and deposition in crude oil trans-
port flow-lines and pipelines is an increasing challenge for the
development of deepwater subsea hydrocarbon reservoirs. There
are several paraffin wax treatment methods. The most common
Contents lists available at SciVerse ScienceDirect
journal homepage: w ww.elsevier.com/locate/petrol
Journal of Petroleum Science and Engineering
0920-4105/$ - see front matter & 2012 Elsevier B.V. All rights reserved.
http://dx.doi.org/10.1016/j.petrol.2012.04.025
n Corresponding author. Fax: þ 60 95492889.
E-mail address: [email protected] (N.H. Abdurahman).
Journal of Petroleum Science and Engineering 90–91 (2012) 139–144
7/21/2019 Petroleum 2012.pdf
http://slidepdf.com/reader/full/petroleum-2012pdf 3/7
removal methods are mechanical heat application using hot oil or
electrical heating, application of chemicals (e.g., solvents, pour-
point dispersants) and the use of microbial products.
Crude oil contains n-paraffin waxes that tend to be separated
from oil when the temperature of crude oil falls below the wax
appearance temperature. With decreasing temperature, the
waxes generally crystallize as an interlocking network of the
sheets, thereby entrapping the remaining liquid fuel in cage-like
structures. When the temperature approaches the pour point,the oil may gel completely causing the cold flow problems such
as blockage of flow pipes or production lines. The pour point is
the lowest temperature at which oil will flow freely under its
own weight under specific test conditions. Several methods
(Bernadiner, 1993; Hunt, 1996) have been available to improve
the low-temperature properties of crude oil. Pretreatment with
pour point depressants (PDD) is an attractive solution for trans-
portation of waxy crude oils via pipelines.
Another promising pipeline technique is the transport of
viscous crudes as concentrated oil-in-water (O/W) emulsions
(Gregoli et al., 2006; Lappin and Saur, 1989). The technical
viability of this method was demonstrated in an Indonesia pipe-
line (Lamb and Simpson, 1963) and in a 20 km-long, 0.203-m-
diameter pipeline in California. In this method, with the aid of
suitable surfactants, the oil phase becomes dispersed in the water
phase and stable oil-in-water emulsions are formed. The forma-
tion of an emulsion causes a significant reduction in the emulsion
viscosity; even O/W emulsion might reduce corrosion with a
crude oil with high sulfur content; corrosion may also appear
with use of an aqueous phase, even with the use of formation
water, rich in salts. The produced emulsions have viscosities in
the range of approximately 0.05–0.2 Pa s. Because of this reduc-
tion in viscosity, the transportation costs and transport-assisted
problems are reduced. This method can be very effective in the
transportation of crude oils with viscosities higher than 1 Pa s
especially in cold regions. In addition, because water is the
continuous phase, crude oil has no contact with the pipe wall,
which reduces pipe corrosion for crudes with high sulfur contents
and prevents the deposition of sediments in pipes, as is common
for crudes with high asphaltene contents (Poynter and Tigrina,
1970). The possibility of injecting aqueous surfactant solution
into a well bore to affect emulsification in the pump or tubing for
the production of less viscous O/W emulsions will increase the
productivity of a reservoir (Simon and Poynter, 1968; Steinborn
and Flock, 1982).
The objective of the current research was to investigate the
various factors affecting the preparation of a stable crude O/W
emulsion for two Malaysian oil samples, Tapis crude oil and a
blend of Tapis and Masilla. The study investigated the influence of
the oil content of the emulsion, the salinity of the water, the
speed and duration of mixing, the pH of the aqueous phase, and
the type and concentration of surfactant.
2. Materials and methods
2.1. Materials
The crude oil samples used in this study were obtained from
Petronas Refinery at Melaka, Malaysia. A detailed procedure for
the preparation of the crude oil-in-water (O/W) emulsions is
given in a previous report by Abdurahman et al. (2006). Here we
merely describe the main experimental steps. Two crude oils
were used; crude A was Tapis, and crude B is a blend of Tapis and
Masilla. Their compositions and fractions are shown in Tables 1,
2 and 3 respectively. For the preparation of crude oil-in-water
emulsions, the agent in water method was implemented; that is
the emulsifying agent was dissolved in the continuous phase
(water), and oil was added gradually to the mixture (waterþ
emulsifying agent). Emulsions were agitated vigorously using a
standard three blade propeller at room temperature (25–30 1C).
The volume of water that settled to the bottom over time was
measured using scale on the beaker. The prepared emulsions
were used to check for W/O or O/W emulsions. All emulsions
investigated were oil-in-water emulsions (water as the contin-
uous phase). The surfactant used in this study was Triton X-100
(polyethylene glycol octylphenyl ether), which has a chemical
formula of C33H60O10. This surfactant is a nonionic hydrophilic
surfactant that is suitable for use in the production of O/W
emulsions.
2.2. Experimental procedure
2.2.1. Sample preparation and procedures
The crude oil samples were obtained from Petronas Refinery at
Malaka city, two types of crude oils were collected. Different
samples of oil-in-water emulsions were prepared using the two
crude oils and tab water. Emulsions were prepared in 500 mL
graduated beakers with ranges by volume of water and oil phase.
The water phase is tab water. The emulsions were agitated
vigorously using a standard three blade propeller. The prepared
emulsion was used to check for W/O or O/W emulsions. All
emulsions investigated were O/W emulsion (water-continuous
phase).
Two series of experiments were performed using two different
samples of crude oils. In both series, the influence of the
surfactant concentration (0.3–2.5 wt%), the speed of mixing
Table 1
Physical properties of crude oils: A and B.
Crude oil Crude A Crude B
Density (gm cm3) 0.874 0.788
Viscosity (Pa s) 0.028 0.010
API gravity 18.0 20.00
Surface tension (mN m1) at 30 1C 30.30 22.50
Interfacial tension (mN m1) at 30 1C 28.80 20.35
Table 2
Chemical properties of the crude oils used in this study.
Crude oil Crude A Crude B
Asphaltenes (wt%) 1.50 0.87
Resins (wt%) 13.50 9.40
Aromatics (wt%) 25.00 23.00
Saturates (wt%) 60.00 66.73
Table 3
Viscosity of crude A and obtained blends B, interfacial tension with oil contents.
Salini ty Oil content Viscosity Interfacial tension
Nacl conc. Crude A Crude B Crude oil A Crude oil B
(%) (vol%) (Pa s) (Pa s) (mN/m) (mN/m)
0 30 1.200 0.900 28.80 20.35
1.5 40 1.620 1.100 28.20 20.26
2.5 50 1.670 1.200 27.77 18.78
3.5 60 1.700 1.270 26.32 15.83
4.5 68 1.780 1.285 24.00 14.44
5.5 70 1.820 1.200 23.66 14.00
5.5 72 1.750 1.190 22.70 13.81
5.5 80 1.890 1.281 21.90 13.56
5.5 85 – 1.290 21.90 12.80
N.H. Abdurahman et al. / Journal of Petroleum Science and Engineering 90–91 (2012) 139–144140
7/21/2019 Petroleum 2012.pdf
http://slidepdf.com/reader/full/petroleum-2012pdf 4/7
(1000–2000 rpm), the duration of mixing (5–15 min), the pH of
the aqueous phase (6–7.8), the salt concentration and the tem-
perature of homogenization (25–90 1C) on the stability and
viscosity of the emulsion was investigated. In each series of
experiments, oil-in-water (O/W) emulsions were prepared using
various amounts of the oil samples while other parameters were
kept constant at desirable values. Therefore, the maximum limit
of oil content for each sample was determined. Beyond that limit,
phase inversion occurred. The phase inversion of crude oil A
(Tapis) occurred at oil content of 72 vol% while crude B (blends
Tapis and masilla) occurred at oil content of 68 vol%.
The emulsion stability was investigated using the following
equation and the results have been tabulated in Table 4:
Emulsion stability ¼ 1water separated ð%Þ
water content ð%Þ ð100Þ
For example: oil content 72%, amount of water separated 7%,
by applying the above equation, the O/W emulsion stability will
be 75%, Table 4.
2.3. Pour point measurement
The pour point of the crude oil samples was measured using
Cloud and Pour Point apparatus Model Stanhope-Seta with Auto
Frigistat. The procedure followed the Standard Test Method
(ASTM Designation D97-93). After preliminary heating, the sam-
ples were cooled at a specified rate and were examined at an
interval of 3 1C. The lowest temperature was recorded as the pour
point at which the movement of the specimen was observed.
3. Results and discussion
3.1. Effect of oil content
The effects of the oil content of the emulsion on its stability,
pour point and dynamic shear viscosity were investigated. Theconcentration of Triton X-100 in water was kept constant, at
3 wt% at a temperature of 50 1C and a pH of 7. The speed and
duration of mixing were 1700 rpm and 15 min, respectively. For
each particular type of crude oil, the oil content of the emulsion
was varied from 30 to 80 vol% with respect to the total volume of
the emulsion.
Table 4 shows the data for the influence of oil content on both
the stability and pour point of the O/W emulsion. It can be seen
from these results that the stability of the emulsion remained
unchanged after six days for the emulsion containing 72 vol%
crude oil A. However, for emulsion containing 70, 60, 50, 40, and
30 vol% crude oil, some water separation occurred; the amounts
of separated water were 30%, 45%, 50%, 65% and 70%. These
results were expected because, as the volume fraction of the
dispersed phase increases, the rate of coalescence increases owing
to the increased entropy for effective collisions between the
dispersed droplets (Menon and Wasan, 1985). The influence of
the oil content of the emulsion on its pour point is a very
important parameter to study; to be sure that the pour point of
the prepared O/W emulsion does not increase and cause trans-
portation problems in pipelines at low temperatures. Therefore,
the pour points of the emulsions with different oil contents were
obtained together with the pour point of Tapis crude oil ( þ20 o
C),and the results are listed in Table 4. For all of the oil contents
studied, the measured pour points were found to be lower than
those of the Tapis crude oil indicating that the formation of an
O/W emulsion for a particular crude oil decreases its pour
point value.
For the different oil contents of the emulsion, the surfactant
concentration was kept constant, with respect to the total emul-
sion volume (0.3 wt%). The surfactant concentration in the aqu-
eous continuous phase (water) increased as the oil content
increased and consequently the water content decreased. The
actual surfactant concentration in the aqueous phase for each oil
content is given in Table 4.
Fig. 1 is a plot of the dynamic viscosity of the emulsion versus
the oil content of the emulsion expressed in vol% at different
temperatures. It is clear from these results that decreasing the oil
content or conversely increasing the water content of the emul-
sion is accompanied by a decrease in the emulsions apparent
viscosity. Fig. 2 again is a plot of the dynamic viscosity of the
emulsion versus the oil content of the emulsion expressed in vol%.
By increasing the oil content up to 72 vol% (Crude Oil A) and
68 vol% (Crude Oil B), the viscosity reached its maximum, beyond
these values, the emulsions slightly decreases. However, beyond
this limit the viscosity increases significantly due to the occur-
rence of phase inversion.
The effective dynamic viscosity of Tapis crude oil decreased
from 2 Pa s to 0.1 Pa s at 30 1C for the 50% oil emulsion. From the
economic point of view, it is more profitable and cost-effective to
reduce the viscosity of the crude oil using the minimum amount
of water.
3.2. Effect of mixing speed on the stability and viscosity of the
emulsion
The effect of the dynamic viscosity of the Tapis crude oil-in-
water emulsion was investigated for five different mixing speeds,
700, 900, 1200, 1500, and 1700 rpm at 50 1C for 15 min at a fixed
Table 4
Stability and pour point of the emulsions containing different oil contents.
Oil
content
% Water separation
after six days at 30 1C
% Emulsion stability
after six days at 30 1C
Surfactant
conc.
Pour
point
(vol%) (wt%) (1C)
100 – – – þ20
80 0 100 2.5 þ12
72 7 75 2.5 þ8
70 12 60 2.5 þ860 18 55 2.0 þ8
50 27 46 1.5 þ6
40 42 30 1.0 þ5
30 48 31.43 0.3 þ5
20 30 40 50 60 70 80 90
Oil Content (Vol.%)
-0.05
0.00
0.05
0.10
0.15
0.20
0.25
0.30
0.35
0.40
0.45
V i s c o s i t y ( P a . s
)
30 oC
50 oC
70 oC
Fig. 1. Dynamic shear viscosity of emulsions as a function of the oil content at
different temperatures.
N.H. Abdurahman et al. / Journal of Petroleum Science and Engineering 90–91 (2012) 139–144 141
7/21/2019 Petroleum 2012.pdf
http://slidepdf.com/reader/full/petroleum-2012pdf 5/7
surfactant concentration (2.5%), using synthetic formation water
as the continuous phase, and with a 72 vol% oil content. From
these observations, it can be deduced that the phase inversion
point is in the range of 68–72% oil. Fig. 3 demonstrates the effect
of mixing speed on the viscosity and stability of the emulsions.
Increasing either the speed or duration of mixing has a similar
effect on the emulsion’s quality. The increase in speed or duration
of mixing has a slight increasing effect on the viscosity of the
emulsions and increases the stability of the emulsions up to a
desirable level. On the other hand, using a mixing speed of less
than 900 rpm and a mixing duration of less than 7 min would
significantly reduce the quality of the emulsions. For a crude oil-
in-water emulsion with a specified volume fraction of crude oiland a specified surfactant concentration, increasing the speed and
duration of mixing increases the production of droplets with
smaller sizes, which causes an increase in the interfacial area and
particle-to-particle interactions, which thus increases the stability
of the emulsion. At the same time, decreasing the size of the oil
droplets, i.e. the dispersed phase, results in a slight increase in the
viscosity of the emulsions (Stachurski and Michalek, 1996; Zaki,
1997). The obtained observations for the increase in the emulsion
viscosity due to the increase in the agitation speed, which
produces droplets of smaller size, are in agreement with the
findings of Pal et al. (1992), as well as with those of Briceno et al.
(1997). As the volume of the dispersed phase increases, the
continuous phase must spread out further to cover all the
droplets. This spreading out of the continuous phase increases
the likelihood of impacts between droplets, thus decreasing the
stability of the emulsion.
3.3. Effect of the surfactant concentration on the stability and
viscosity of the emulsion
The surfactant concentration required for stabilizing the emul-
sion and forming an emulsion with acceptable viscosity was
investigated. To prepare the O/W emulsions, the oil content of the emulsion was kept constant at its optimum value, i.e. 72 vol%,
the other conditions were a temperature of 30 1C, pH of 7, a
mixing speed of 1700 rpm and a mixing duration of 15 min. The
concentration of Triton X-100 surfactant in water was varied from
0.125 to 1.5 wt%. Fig. 4 illustrates the effect of the surfactant
concentration on the viscosity and stability of the emulsions.
Increasing the concentration of the surfactant resulted in a
slight increase in the viscosity of the emulsion, and the stability
significantly increased. Increasing the surfactant concentration
results an increase in the number of barriers between the two
phases and provides a better distribution of dispersed droplets in
the continuous phase. It is notable that Triton X-100 is a viscous
liquid. Thus increasing its concentration in the emulsion increases
the viscosity of the emulsion (Eirong and Lempe, 2006). At thesame time, increasing the surfactant concentration reduces the
interfacial tension, which facilitates the splitting of droplets into
smaller ones. The latter would result in a more stable emulsion
with a higher viscosity (Sakka, 2002). It is clear from the above
mentioned results that, increasing the surfactant concentration
increases the emulsion stability; this increase in stability could be
correlated to the oil/water IFT. Fig. 5 depicts a plot of the
surfactant concentration in the synthetic formation water versus
the crude oil/water IFT measured at 30 1C. As clearly demon-
strated by this figure, the increase in the surfactant concentration
results in an increase in the number of surfactant molecules
adsorbed at the oil–water interface. The adsorbed surfactant
molecules provide a steric barrier to the coalescence of the
dispersed oil droplets as a result of the nonionic nature of the
surfactant Singh and Pandey (1991). The appropriate surfactant
concentration should be chosen based on the surfactant cost and
the economy of the process.
3.4. Effect of temperature on the stability and viscosity of the
emulsion
One of the important methods that can be used to lower the
viscosity of heavy crude oil and therefore to enhance the flow-
ability is to change the temperature. Temperature has a strong
20 30 40 50 60 70 80 900.8
1
1.2
1.4
1.6
1.8
2
Oil content (vol.%)
V i
s c o s i t y ( P a . s
)
Crude oil A
Crude oil B
Fig. 2. Dynamic viscosity versus the oil content of the emulsion.
600 800 1000 1200 1400 1600 1800
Mixing Speed (rpm)
-0.2
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
2.2
V i s c o s i t y ( P a . s
)
30 oC
40 oC
60 oC
Fig. 3. Dynamic viscosity of the emulsions as a function of mixing speed.
Fig. 4. Emulsions stability as a function of mixing speeds at constant temperature
and surfactant concentration.
N.H. Abdurahman et al. / Journal of Petroleum Science and Engineering 90–91 (2012) 139–144142
7/21/2019 Petroleum 2012.pdf
http://slidepdf.com/reader/full/petroleum-2012pdf 6/7
effect on viscosity and viscous behavior. This effect determines
the flow behavior of the crude oil in terms of the viscosity–shear
rate relationships. Fig. 6 shows the effect of temperature on the
viscosity–shear rate for heavy crude oil over the range of 30–80 1C
in 101 increments. The crude oil shows non-Newtonian shear
thinning behavior over the range of shear rates from 75 to
700 s1 in which the apparent viscosity decreases considerably
with temperature and is reduced by one half when it is heated
from 30 to 80 1C. The viscosity differences were larger at low
shear rates than at high shear rates.
3.5. Effect of pH on emulsion stability
Water phase pH has a strong influence on emulsion stability.
The stabilizing, rigid-emulsion film contains organic acids and
bases, asphaltenes with ionizable groups, and solids. Adding
inorganic acids and bases strongly influences their ionization in
the interfacial films and radically changes the physical properties
of the film by the charges at the interface, along with the
electrostatic double layer repulsion effect. The pH of the water
affects the rigidity of the interfacial films. Brine composition has an
important effect (in relation to pH) on emulsion stability. Fig. 7
shows the effect of a bicarbonate brine and fresh water on
emulsion stability as a function of pH. Optimum pH (for water
separation) changes from approximately 10 for fresh water to 7 for
brine solution. This is because of the ionization effect (i.e., associa-
tion/interaction of ions present in the brine with the asphaltenes).
4. Conclusions
The oil-in-water (O/W) emulsions were successfully prepared
using two crude oil samples, the Tapis and a blend of Tapis and
Masilla. The effective viscosity of the two crude oils decreased
when it was emulsified with water in the presence of Triton
X-100. The viscosity of the emulsion was found to decrease as the
oil content of the emulsion decreased, the speed of mixing
decreased, and the salinity of the aqueous phase decreased.
The stability of O/W emulsions of both samples was found to
decrease as the oil content of the emulsion increased up to the
phase inversion point. After this point the emulsion converts to a
W/O emulsion, and the stability of the emulsion begins to
increase with increasing oil content. The phase inversion of crude
oil A (Tapis) occurred at oil content of 72 vol% while crude B
(blend Tapis and masilla) occurred at oil content of 68 vol%.
The stability of O/W emulsions of both samples was found to
increase with increases in the surfactant and salt concentrations,
the speed and duration of mixing, the pH of the aqueous-phase
and the temperature of homogenization.
References
Abdurahman, H.Nour, Rosli, M.Y, Zulkifly, J, 2006. Study on demulsification of water-in-crude oil emulsions via microwave heating technology. J. Appl. Sci. 6,2060–2066.
Briceno, M., Isabel, R.M., Bullon, J., Salager, J.I, 1997. Customizing drop sizedistribution to change emulsion viscosity. In: Proceedings of the 2nd WorldCongress on Emulsion-2eme Congres Mondial de I’Emulsion CME2, Paper 2-1-094, Bordeaux, France.
Bernadiner, M.G., 1993. Advanced asphaltene and paraffin control technology.Presented at the International Symposium on Oilfield Chemistry, SPE paper no.25192, New Orleans, LA, pp. 2–5.
Chilingar, G.V., Yen, T.F., 1980. Enhanced Recovery of Residual and Heavy Oils. In:Schumacher, M.M. (Ed.), 2nd ed. Noyes Data Corporation, Part Ridge, NJ,
pp. 403–418.Eirong, J.I., Lempe, D.A., 2006. Calculation of viscosities of liquid mixtures usingEyring’s theory in combination with cubic equations of state. Chin. J. Chem.Eng. 14 (6), 770–779.
Gregoli, A.A., Hamshar, J.A., Olah, A.M., Riley, C.J., Rimmer, D.P., 2006. Preparationof Stable Crude Oil Transport Emulsions. US Patent no. 4,725,287.
Hunt, A., 1996. Uncertainties remain in predicting paraffin deposition. Oil Gas J.5, 96–103.
Iona, M., 1978. Process for Producing Low-Density Low Sulfur Crude Oil. US Patentno. 4,092,238.
Lanier, D., 1998. Heavy oil—a major energy source for the 21st century. In:Proceedings of the 7th Unitar International Conference on Heavy Crude & TarSands, Paper no. 1998.039, Beijing, China.
Langevin, D., Poteau, S., Henaut, I., Argillier, J.F., 2004. Crude oil emulsion proper-ties and their application to heavy oil transportation. Oil Gas Sci. Technol. —Rev. IFP 59 (5), 511–521.
Layrisse, R., 1998. Viscous Hydrocarbon-in-water Emulsions. US Patent no.4,795,478.
Lappin, G.R., Saur, J.D., 1989. Alpha Olefins Applications Handbook. CRC Press,
New York.
Fig. 5. Interfacial tension as a function of water salinity at different surfactant
concentrations.
0 100 200 300 400 500 600 700 800
Shear Rate (s-1)
5
6
7
8
9
10
11
V i s c o s i t y ( P a . s
)
30 oC
40 oC
50 oC
60 oC
70 oC 80 oC
Fig. 6. Effects of temperature on the viscosity of heavy crude oil.
0 2 4 6 8 10 12
0
10
20
30
40
50
60
70
80
90
% W
a t e r S e p a r a t i o n
pH
Brine solution
Fresh water
Fig. 7. Effect of brine and pH on emulsion stability.
N.H. Abdurahman et al. / Journal of Petroleum Science and Engineering 90–91 (2012) 139–144 143
7/21/2019 Petroleum 2012.pdf
http://slidepdf.com/reader/full/petroleum-2012pdf 7/7
Lamb, M.S., Simpson, W.C., 1963. Proceedings of the Sixth World PetroleumCongress, Section VII, p. 50.
MacWilliams, M.A., Eadie, W., 1993. Process and Apparatus for Partial Upgrading.Canadian Patent no. 1313639.
Menon, VB., Wasan, DT., 1985. Encycl. Emulsion Technol. 2, 1.Pal, R., Yan, Y., Masliyah, J.H., 1992. In: Schramm, L.L. (Ed.), Emulsions Funda-
mentals and Applications in the Petroleum Industry. American ChemicalSociety, Washington DC, pp. 141–145.
Plegue, T.H., Frank, S.G., Zakin, J.L., 1989. Studies of water-continuous emulsions of heavy crude oils prepared by alkali treatment. SPE Prod. Eng. 4 (2), 181–183.
Poynter, G., Tigrina, S., 1970. Pipelining O/W Mixtures. US Patent no. 3,519,006.
Rana, S.Mohan, Vicente, S., Jorge, A., Diaz, J.A.I., 2007. A review of recent advanceson process technologies for upgrading of heavy oils and residua. Fuel 86(2007), 1216–1231.
Rafael, Martinez-Palou, Maria de Lourdes, M., Beatriz, Z.R., Elizabeth, M.J., Cesar,B.H., Juan De La Cruz, C.L., Jorge, A., 2011. Transportation of heavy and extra-heavy crude oil by pipeline: a review. J. Pet. Sci. Eng. 75 (2011), 274–282.
Saniere, A., Henaut, I., Argillier, J.F., 2004. Pipeline transportation of heavy oils, a
strategic, economic and technological challenge. Oil Gas Sci. Technol.—Rev. IFP
59 (5), 455–466.Singh, BP., Pandey, BP., 1991. Surfactants and interfacial phenomena. Indian J.
Technol. 29, 443.Simon, R., Poynter, WC, 1968. J. Pet. Technol. 1968 (20), 1349.Stachurski, J., Michalek, M., 1996. The effect of the z potential on the stability of a
non-polar oil-in-water emulsion. J. Colloid Interface Sci. 184 (2), 433–436.Steinborn, R., Flock, D.L., 1982. Presented at 33rd Annual Meeting of the Petroleum
Society of CIM, Alberta, Canada, 1982.
Sakka, S., 2002. Sol–Gel Science and Technology Topics in Fundamental Researchand Applications. Sol–gel Prepared Ferroelectrics and Related Materials, 1.
Kluwer Academic Publisher, New York 33–35 pp.Zaki, N., 1997. Surfactant stabilized crude oil-in-water emulsions for pipeline
transportation of viscous crude oils. Colloids Surf. A: Physicochem. Eng.
Aspects 125 (1), 19–25.
N.H. Abdurahman et al. / Journal of Petroleum Science and Engineering 90–91 (2012) 139–144144