International Journal of Petroleum Science and Technology
ISSN 0973-6328 Volume 14, Number 1 (2020), pp. 1-12
© Research India Publications
http://www.ripublication.com
Evaluation of the Impacts of using Single and Combined
Low Cost Surfactants on Enhanced Oil Recovery
Obeta Perpetual Oby, Odey Michael Ekpali, Azuokwu Augustine Azubike*,
Randolph Deh Opute, Azike Rowland Ugochukwu.
Chemical & Petroleum Engineering Department, Igbinedion University,
Okada. Edo State, Nigeria.
E-mail: [email protected]
*Corresponding author
ABSTRACT
Due to the high cost of most surfactants used in the oilfield enhanced oil
recovery, this study was conducted to evaluate the impacts of using single and
combined low cost surfactants (Teepol and Tween 80). In the study oil and
water wet porous media were subjected to water flooding followed by
surfactants.
Water flooding operations yielded an average recovery factor of 46.42 % and
52.59 % and an average displacement efficiency of 49.3% and 55.2 % for oil
wet and water wet systems respectively.
After water flooding operations and subsequent surfactant flooding with
Teepol (anionic surfactant), a recovery factor of 64.69% and 73.52 % and a
displacement efficiency of 69.33% and 72.82% were obtained for oil wet and
water wet systems respectively. The water flooding and the subsequent
surfactant flooding operations with Tween 80 (nonionic surfactant) resulted to
the displacement efficiencies and recovery factors of 73.27% and 76.89% and
67.60% and 77.33% for the oil wet and water wet systems respectively. The
results further showed that both surfactants are good enhanced oil recovery
agents however Tween 80 was better than Teepol for light oil recovery.
The displacement efficiencies and recovery factors obtained due to water
flooding and the synergy of the two surfactants for the oil wet and water wet
systems were 71.89% and 75.19% and 66.15% and 75.08% respectively,
which showed positive synergies between anionic and nonionic surfactants.
Results further showed that both the water flooding and surfactants flooding
operations were more favourable in water wet systems than in oil wet systems.
Keywords: Single and Combined Low Cost Surfactants, Water Flooding,
Surfactant Flooding, Recovery Factor, Displacement Efficiency
2 Obeta Perpetual Oby et al
1. INTRODUCTION
The field of enhanced oil recovery (EOR) has received more attention in recent years
due to constant rise in the demand for crude oil and the corresponding depletion in
conventional reserves coupled with the desire to improve oil recovery beyond primary
and secondary recovery. Studies have shown that the overall recovery factors for
combined primary and secondary recovery range between 35 and 45% [1-4]. The
remaining oil left after primary and secondary recovery operations over long-time
periods is usually distributed in pores in the reservoir, where the oil is trapped, mainly
due to capillary forces and viscous forces [5-7]. EOR is oil recovery by injection of
gases or chemicals and/or thermal energy into the reservoir [8]. The basic
mechanisms of EOR include increasing volumetric sweep efficiency and enhancing
displacement efficiency through IFT reduction and decrease in mobility ratio [9, 10].
Among the various EOR methods, Chemical Enhanced Oil Recovery (CEOR) has
been used worldwide for many decades and the fundamental CEOR is the Surfactant
Flooding [11]. According to [12], surfactants are chemical substances that adsorb on
or concentrate at a surface or fluid/fluid interface when present at low concentrations
in a system. They consist of a lipophilic portion (hydrocarbon group) and hydrophilic
portion (polar group) which are the non-polar (tail) and polar (head) portions
respectively [13].
Wettability and interfacial tension are significant issues in oil recovery [14-16].
Surfactant flooding enhances oil recovery through the mechanism of interfacial
tension reduction, or wettability alteration, or a combination of both mechanisms
[11, 17].
Several surfactants are available for enhanced oil recovery. They are majorly
classified into anionic surfactants, non-ionic surfactants, cationic surfactants and
zwitterionic surfactants. [18]. Surfactants can be used single or combined form
during flooding operations [19-22].
Surfactant flooding has been rated as one of the effective and widely applied
enhanced oil recovery process [23]. However, due cost of most surfactants, efforts
have been focused on the search for alternatives, and improvement on the existing
low cost oilfield surfactants [23-24, 17].This study was therefore conducted to
evaluate the impacts of using single and combined low cost surfactants on oil
recovery.
2. MATERIALS AND METHODS
2.1 Materials
(a) Low Surfactants [(i) Teepol (ii) Tween 80]
Teepol is an anionic surfactant by shell and has a density of 1.03g/ml at 20oC.
The teepol comprises Myristyl trimethyl ammonium bromide and hydrogen
peroxide (H2O2)
Evaluation of the Impacts of using Single and Combined Low Cost Surfactants… 3
Tween 80 also called Polysorbate 80 is a nonionic surfactant and emulsifier.
This synthetic compound is a viscous, water-soluble yellow liquid. It has a
molar mass 1310g/mol, a Chemical formula C64H124O26, a density of 1.06-1.09
g/mol and oily liquid.
(b) Crude oil (light), 32˚API
(c) Glass Beads (Soda Lime Glass Spheres) - Class IV Soda Lime Glass Spheres
from MO-SCI Speciality Products, L.L.C, A subsidiary of MO-SCI
Corporation 4040 Hypoint North Rolia, MO 65401 USA were used as porous
media in all flooding experiments. The Glass beads have a particle size
distribution of -60 +80 mesh.
(d) Others materials include Brine- NaCl, H2SO4, kerosene.
(e) Apparatus- Core holder (bulk volume of 112.9 cc), peristaltic pump, beakers,
stop watch, measuring Cylinders, Fann Viscometer, Magnetic Stirrer, UPS,
Weighing Balance and Oven
2.2 Methods
The processes involved in this work include glass beads preparation, slug preparation,
Porous media preparation and flooding experiments.
Glass Bead Preparation
Glass bead of 80 microns was used all through this experiment. Water wet and oil wet
beads samples were prepared and used.
100% Water Wet Glass Bead
About 1400g of dry glass bead was washed and treated with 5% of H2SO4 solution to
etch it for the removal of any organic substances attached to it. The etched glass bead
was properly rinsed to remove H2SO4 with sufficient water. Water was sieved out and
dried in an oven for about 48 hours. The dry glass bead was labeled 100% water wet.
100% Oil Wet Glass Bead
About 700g of the dried water wet glass bead was measured, properly soaked and
mixed in kerosene. The kerosene coats the surface of the glass beads particles
increasing its affinity for oil (oil wet). Kerosene was sieved out from the glass bead.
Kerosene- treated glass bead was oven dried as shown below for about 72 hours to
attain a completely oil wet beads.
Reagents Preparation
(a) Brine Preparation
2% by weight of NaCl was measured and added to 98% pure water in a beaker to
form the brine solution. The solution was stirred with a magnetic stirrer to form a
uniform solution for about 10 minutes.
4 Obeta Perpetual Oby et al
(b) Surfactant Preparation
The surface active substance used in this experiment was Teepol and Tween 80.
Teepol slug and Tween 80 slug were used at a concentration of 0.9% prepared with
magnetic stirrer. Thus, 0.9% by weight of surfactants, Teepol and Tween were
measured into a 99.1% brine solution (2% NaCl) and stirred with a magnetic stirrer to
attain a uniform surfactant solution to obtain two slugs. Also 0.45% of Teepol and
0.45% of Tween were missed together in 99.1% brine to constitute a mixture of the
two surfactants.
Flooding Experimental
Six different flooding experiments were performed as shown in Table 1. Water
flooding was followed by surfactants flooding. The experimental set is shown in
Figure 1.
The experimental procedures are in tandem to those stated by Oluwaseun et al. [25],
with some modification and are outlined below:
i. The core holder was loaded with glass bead (soda lime glass spheres) and
vibrated as incremental loading takes place to remove air bubbles and ensure
uniform distribution of grains in the porous media.
ii. The weight of the core holder with the glass bead is measured.
iii. Core holder was held vertically in a retort stand and completely flooded with
the 2% brine solution at a flow rate of 0.8cc/min to avoid fingering. The core
holder is then weighed and the pore volume calculated.
iv. Oil saturation was carried out by flooding the porous media horizontally with
light dead oil at a flow rate of 2.0cc/min and the water displaced from the core
holder is collected in test tubes. Drainage continues for about one hour until
water cut is less than one percent. This was done to determine the initial oil
saturation and residual water saturation. The effluent fluid was collected in
100ml measuring cylinders. The volume of displaced water is equivalent to the
volume of oil injected (steady state).
The displacement efficiency 𝑬𝑫 was calculated as:
v. 2% brine solution was used to perform water flooding at a flow rate of
2.0cc/min. The breakthrough time was recorded. Water flooding continues
until a water cut of approximately 96%. This is done to determine residual oil
saturation estimated based on the volume of oil collected in the measuring
cylinders.
vi. 0.7 PV of the 0.9% concentration of Teepol surfactant, Tween 80, and the
mixture of the two surfactants were injected into the porous media at a flow
rate of 2.0cc/min at different time. This help to reduce the interfacial tension
holding back the residual oil in the porous media after water flooding and
release the trapped oil.
Evaluation of the Impacts of using Single and Combined Low Cost Surfactants… 5
These procedures were followed for the six different experiments with different
wettability and surfactant slugs.
The following calculations were made.
𝑃𝑉 = (𝑊𝐶𝐻+ 𝑏𝑟𝑖𝑛𝑒 𝑠𝑎𝑡𝑢𝑟𝑎𝑡𝑒𝑑 𝑔𝑙𝑎𝑠𝑠 𝑏𝑒𝑎𝑑𝑠 − 𝑊𝐶𝐻+𝑑𝑟𝑦 𝑔𝑙𝑎𝑠𝑠 𝑏𝑒𝑎𝑑𝑠
𝑆𝑝𝑒𝑐𝑖𝑓𝑖𝑐 𝐺𝑟𝑎𝑣𝑖𝑡𝑦 𝑜𝑓 𝐵𝑟𝑖𝑛𝑒)
− (𝑑𝑒𝑎𝑑 𝑣𝑜𝑙𝑢𝑚𝑒) … … … . (1)
Where:
Specific gravity of brine = 0.01197 and Dead Volume = 2.4cc.
W= Wight, CH= Core Holder.
The Porosity is calculated as:
𝑃𝑜𝑟𝑜𝑠𝑖𝑡𝑦 =𝑃𝑜𝑟𝑒 𝑉𝑜𝑙𝑢𝑚𝑒
𝐵𝑢𝑙𝑘 𝑉𝑜𝑙𝑢𝑚𝑒… … … (2)
The displacement efficiency 𝐸𝐷 was also calculated as:
𝐸𝐷 =𝑆𝑜𝑖 − 𝑆𝑜𝑟
𝑆𝑜𝑖 = 1 −
𝑆𝑜𝑟
𝑆𝑜𝑖 … … (3)
ℎ𝑜𝑙𝑑𝑒𝑟 𝑤𝑖𝑡ℎ 𝑑𝑟𝑦 𝑔𝑙𝑎𝑠𝑠 𝑏𝑒𝑎𝑑𝑠
Figure 1. Experimental Set-Up
6 Obeta Perpetual Oby et al
Table 1. Experimental Nomenclature
SN Expt. Wettability Initial Flooding Subsequent
Surfactant Flooding
1 X1 Oil Wet (oil wet porous media.) Brine Solution Teepol
2 X2 Water wet (water wet porous media) Brine Solution Teepol
3 Y1 Oil Wet (oil wet porous media.) Brine Solution Tween 80
4 Y2 Water Wet (water wet porous media) Brine Solution Tween 80
5 Z1 OILWET (oil wet porous media.) Brine Solution Teepol + Tween 80
6 Z2 Water Wet (water wet porous media) Brine Solution Teepol + Tween 80
3. RESULTS AND DISCUSSION
The results the studies are presented in Figure 2 to Figure 5.
Figure 2. Result of Flooding Experiments
Figure 3. Result of Displacement Efficiency (Water Flooding)
0.0
5.0
10.0
15.0
20.0
25.0
30.0
35.0
Expt. X1(Teepol +
Oil WetPorousMedia)
Expt. X2(Teepol +
Water WetPorousMedia)
Expt.Y1(Tween 80+ Oil Wet
PorousMedia)
Expt.Y2(Tween 80
+ WaterWet
PorousMedia)
Exp. Z1(Teepol+Tween 80+ Oil Wet
PorousMedia)
Exp. Z2(Teepol+Tween 80++ Water
WetPorousMedia)
Qu
an
tity
of
Oil (c
c)
Flooding Experiments
Initial Oil in Place (cc)
Oil Recovery due to WaterFlooding (cc)
Additional Oil Recovery dueSurfactant Flooding (cc)
Total Oil Recovery (cc)
0
10
20
30
40
50
60
Porous MediaDis
pla
cem
ent
Eff
icie
ncy
(%
)
Water Flooding Experiments
Average Displacement Efficiency dueto Water Flooding (Oil Wet PorousMedia)
Average Displacement Efficiency dueto Water Flooding (Water WetPorous Media)
Evaluation of the Impacts of using Single and Combined Low Cost Surfactants… 7
Figure 4: Result of Displacement Efficiency due to water flooding and Surfactant
Flooding
Figure 5. Recovery Factors due Water Flooding and Surfactants Flooding
3.1. Water Flooding
For the Oil Wet porous media, the volume oil recovered after water flooding
operations, were 14.8cc for Expt.X1, 15.0 cc for Expt.Y1 and 14.9cc for Expt.Z1
(Figure 2). For the Water Wet porous media, the volume oil recovered after water
flooding operations, were 16.8cc for Expt.X2, 17.0cc for Expt.Y2 and 16.9cc for
Expt.Z2 (Figure 2).
64
66
68
70
72
74
76
78
Displacement Efficiency due to Water flooding & SurfactantFlooding
Dis
pla
cem
ent
Eff
icie
ncy
(%
)
Flooding Experiments
Expt. X1 (Teepol + Oil Wet Porous Media)
Expt. X2 (Teepol + Water Wet PorousMedia)
Expt.Y1 (Tween 80 + Oil Wet PorousMedia)
Expt.Y2 (Tween 80 + Water Wet PorousMedia)
Exp. Z1 (Teepol+ Tween 80 + Oil WetPorous Media)
Exp. Z2 (Teepol+ Tween 80 +Water WetPorous Media)
0
10
20
30
40
50
60
70
80
90
Expt. X1(Teepol +
Oil WetPorousMedia)
Expt. X2(Teepol +
Water WetPorousMedia)
Expt.Y1(Tween 80+ Oil Wet
PorousMedia)
Expt.Y2(Tween 80
+ WaterWet
PorousMedia)
Expt. Z1(Teepol+Tween 80+ Oil Wet
PorousMedia)
Expt. Z2(Teepol+Tween 80++ Water
WetPorousMedia)
Re
cove
ry F
acto
r (%
)
Flooding Experiments
AdditionalRecovery Factordue SurfactantFlooding (%)
Recovery Factordue to WaterFlooding (%)
8 Obeta Perpetual Oby et al
For the Oil Wet porous media, the Recovery Factor after water flooding operations,
were 46.25 %for Expt.X1, 46.73 % for Expt.Y1 and 46.27 %for Expt.Z1. For the
Water Wet porous media, the Recovery Factor after water flooding operations, were
52.34 %for Expt.X2, 52.80 % for Expt.Y2 and 52.65 % for Expt.Z2. Thus the average
recovery factor for the oil wet porous media obtained from water flooding operations
was 46.42 % as compared to 52.59 % obtained in water wet porous media. This
showed that water-wet system exhibited greater oil recovery under water flooding
than oil-wet system.
For the Oil Wet porous media, the average displacement efficiency after water
flooding operations was 49.3% while for the Water Wet porous media, the average
displacement efficiency after water flooding operations was 55.2 %. This further
showed that water flooding favoured of water wet beads pack than oil wet bead.
3.2. Surfactant Flooding
The injection of Teepol into the beads pack after water flooding in the oil wet beads
resulted to additional oil recovery of 5.90cc (18.44% of the Initial Oil in place). The
total displacement efficiency and recovery factor due to water flooding and surfactant
flooding with Teepol in oil wet beads were 69.33% and 64.69% respectively. In water
wet beads pack, a further 6.80cc (21.18% of the Initial Oil in Place) was recovered
with Teepol. The total displacement efficiency and recovery factor due to water
flooding and surfactant flooding with Teepol in oil wet beads were 72.82% and 73.52
% respectively. These results showed that flooding with the anionic surfactant was in
favour of water wet systems (Figure 4 and 5).
Tween 80 recovered about 6.70cc (20.87% of the Initial Oil in place) in oil wet and
7.90cc (24.53% of the Initial Oil in place) in water wet packs after water flooding
operations. The displacement efficiencies recorded due to water flooding and
surfactant flooding with Tween 80 for the oil wet and water wet systems were 73.27%
and 76.89% respectively. The recovery factors obtained due to water flooding and
surfactant flooding with Tween 80 for the oil wet and water wet systems were 67.60%
and 77.33% respectively. These results showed that flooding with the nonionic
surfactant was more favourable to water wet systems (Figure 4 and 5).
Flooding with the mixture of the two surfactants resulted to a further recovery of
6.40cc (about 19.88%) for oil wet condition and 7.20cc (about 22.43%) for the water
wet condition. The displacement efficiencies recorded due to water flooding and the
synergy of the two surfactants for the oil wet and water wet systems were 71.89% and
75.19% respectively. The recovery factors obtained due to water flooding and the
synergy of the two surfactants for the oil wet and water wet systems were 66.15% and
75.08% respectively.
The study further showed that both surfactants are good enhanced oil recovery agents
however Tween 80 was better than Teepol for light oil recovery at a concentration of
0.9% (Figure 5). Tween 80 has been noted for its IFT reduction and wettability
alteration abilities [26-29]. The results of the injection of mixtures of 0.45% of Tween
Evaluation of the Impacts of using Single and Combined Low Cost Surfactants… 9
80 (a nonionic surfactant and emulsifier) and 0.45% of Teepol (an anionic surfactant)
into the beads pack after water flooding showed a positive synergy between anionic
and nonionic surfactants. The results of the synergisms between the two surfactants
were more favourable to water wet systems than oil wet systems (Figure 4 and 5).
3.3. Visual Observation
Figure A1 showed the effluent from the Injection of Tween 80, while Figure A2
showed that from Teepol injection. It can be observed that the effluent of Tween 80
has a cloudy phase below the oil. This is a region of low interfacial tension and micro-
emulsion, while for that of Teepol, the phase below the oil level is clearer which
shows that the interfacial tension between the oil and water is higher that of the
previous.
4. CONCLUSIONS
In this study, the impacts of using single and combined low Cost Surfactants in
enhanced oil recovery were determined. Teepol, an anionic surfactant and Tween 80 a
nonionic surfactant were used in the study. The processes involved in this work
include glass beads preparation, slug preparation, Porous media preparation and
flooding experiments (water flooding followed by surfactants flooding).
Water flooding operations yielded an average recovery factor of 46.42 % and 52.59 %
and an average displacement efficiency of 49.3% and 55.2 % for oil wet and water
wet systems respectively. These showed that water flooding is more favourable with
of water wet systems.
After water flooding operations and subsequent surfactant flooding with Teepol, a
recovery factor of 64.69% and 73.52 % and a displacement efficiency of 69.33% and
72.82% were obtained for oil wet and water wet systems respectively. Thus water
flooding operations and the subsequent surfactant flooding with Teepol was more
favourable with water wet systems.
The water flooding operations and subsequent surfactant flooding with Tween 80
resulted to the displacement efficiencies and recovery factors of 73.27% and 76.89%
and 67.60% and 77.33% for the oil wet and water wet systems respectively. These
showed that water flooding operations and the subsequent surfactant flooding with
Tween 80 is more favourable with water wet systems.
The study further showed that both surfactants are good enhanced oil recovery agents
however Tween 80 was better than Teepol for light oil recovery.
The displacement efficiencies and recovery factors obtained due to water flooding and
the synergy of the two surfactants for the oil wet and water wet systems were 71.89%
and 75.19% and 66.15% and 75.08% for the oil wet and water wet systems
respectively. These results showed positive synergies between anionic and nonionic
surfactants. The synergisms between the two surfactants were more favourable to
10 Obeta Perpetual Oby et al
water wet systems than oil wet systems.
REFERENCES
[1] Alain Labastie. “Increasing Recovery Factors: A Necessity”. JPT August 2011
[2] Zitha, P., Felder, R., Zornes, D., Brown, K. and Mohanty, K. (2011).
“Increasing Hydrocarbon Recovery Factors” Society of Petroleum Engineers
(SPE) International Journal of Applied Science and Technology Vol 1 No 5 pp
2-9
[3] Zeinolabedini Hezave, A., Dorostkar, S., Ayatollahi, Sh., Nabipour, M., and
Hemmateenejad, B.(2013): “Investigating The Effect of Ionic Liquid (1-
Dodecyl-3 Methylimidazolium Chloride on the Water/Oil Interfacial Tension as
a Novel Surfactant, Colloids and Surfaces A: Physicochemical and Engineering
Aspects, Vol. 421, p. 63-71, 2013.
[4] Carlos Alvarez (2017): “Oil Reserves Associated with IOR Projects:
Recommendations for the Design of Pilot Tests” Gaffney, Cline and Associate.
[5] Lake, L. W.( 1989): Enhanced Oil Recovery, Prentice-Hall, Englewood Cliffs,
NJ,
[6] Don W. Green, G. Paul Willhite (1998): “Enhanced Oil Recovery”. Henry L.
Doherty Memorial Fund of AIME, Society of Petroleum Engineers, 1998.
[7] Larry W. Lake, Russell Johns, Bill Rossen and Gary Pope (2014):
“Fundamentals of Enhanced Oil Recovery”. Society of Petroleum Engineers,
ISBN: 978-1-61399-328-6.
[8] James J. Sheng (2011): “Modern Chemical Enhanced Oil Recovery Theory and
Practice”. Gulf Professional Publishing, © Elsevier Inc.
https://doi.org/10.1016/C2009-0-20241-8,
[9] Morrow, R. N. (1991):“Interfacial Phenomena in Petroleum Recovery”, Vol. 36,
Pp 325-326.
[10] Sandersen, S. B. (2012). Enhanced Oil Recovery with Surfactant Flooding. Kgs.
Lyngby: Technical University of Denmark (DTU).
[11] Vishal Kumar Makwana, Nayan Medhi, Sabyasaachi Karmakar, Sumedha
Bhattacharya, Niket Agarwal, (2017): “Role of Surfactant and Salinity on
Crude Oil-Water Interfacial Tension in a part of an Oilfield of Upper Assam
Basin”. IJREAS).
[12] Rosen, Milton J. (2004). “Surfactants and Interfacial Phenomena”, TB. 3rd Ed.
[13] Porte M.R, (1994): “Handbook of Surfactants”, 2nd ed. Blackie Academic &
Professional Press, London, 1994, 99-102.
[14] Dake L.P. (1998): “fundamentals of reservoir engineering”. Seventeenth
impression Edition Elsevier, pp 337-339.
[15] Tarek Ahmed (2010): “Reservoir engineering handbook”, Gulf Professional
Evaluation of the Impacts of using Single and Combined Low Cost Surfactants… 11
Publishing © 2010 ELSEVIER Inc. pp 199.
[16] Crain, E. R.(2015): “Wettability Of Porous Rocks”, Crain’s Petrophysical Hand
book.
[17] Afeez O. Gbadamosi, Radzuan Junin, Muhammad A. Manan, Augustine Agi,
Adeyinka S. Yusuff (2019): “An overview of chemical enhanced oil recovery:
recent advances and prospects”.
https://link.springer.com/article/10.1007/s40089-019-0272-8
[18] Susanna Laurén (2019): “Why is wettability important in enhanced oil
recovery”? Biolin Scientific,
[19] El-Batanoney M., Abdel-Moghny Th., Ramzi M. (1999): “The effect of mixed
surfactants on enhancing oil recovery” Journal of Surfactants and Detergents.
Volume 2,Issue 2, pp 201–205
[20] Yincheng Li, Weldong Zhang, Bailing Kong, Maura Puerto, Xinning Boa, Ou
Sha,SZhiqin Shen, Yiqing Yang, Yanhua Liu, Songyuan Gu, Clarence Miller
and George J. Hirasaki (2016) “Mixtures of Anionic/Cationic Surfactants: A
New Approach for Enhanced Oil Recovery in Low-Salinity, High-Temperature
Sandstone Reservoir”. Copyright SPE 2016.
[21] Rashimi Kumar, Abhijit Kakati, Nagarajan R., and Jitendra Sangwai S (2019):
“Synergistic effect of mixed anionic and cationic surfactant systems on the
interfacial tension of crude oil-water and enhanced oil recover”.Journal of
Dispersion Science and Technology,V olume 40, 2019 - Issue 7
doi.org/10.1080/01932691.2018.1489280.
[22] Nilanjan Pal, Mudit Vajpayee, Ajay Mandal (2019) Cationic/Nonionic Mixed
Surfactants as Enhanced Oil Recovery Fluids: Influence of Mixed Micellization
and Polymer Association on Interfacial& Rheological Rock-Wetting
Characteristics Copyright © 2019 American Chemical Society,
doi.org/10.1021/acs.energyfuels.9b00671
[23] Adeniyi A.T., Onyekonwu M.A.,Olafuyi O.A., Sonibare L.O. (2015);
Development of Cost Effective Surfactants from Local Materials for Enhanced
Oil Recovery” SPE- 178403
[24] Ojo T.I. and Fadairo A. S. (2017): “Effect of Jatropha Bio-Surfactant on
Residual Oil during Enhanced Oil Recovery Process”. International Journal of
Applied Engineering Research ISSN 0973-4562 Volume 12, Number 20 (2017)
pp. 10036-10042.
[25] Oluwaseun Ayodele Taiwo, Orivri Uzezi, Abbas Mamudu, Sean Onuoha,
Ogienagbon Adijat, Olalekan Olafuyi (2016): Fractional Wettability Effects on
Surfactant Flooding for Recovering Light Oil Using Teepol”. SPE-184298-MS
https://doi.org/10.2118/184298-MS
[26] Jinhui Feng, Yiyong Zeng, Cuiqing Ma, Xiaofeng Cai, Quan Zhang, Mingyou
Tong, Bo Yu, and Ping Xu (2006): “The Surfactant Tween 80 Enhances
Biodesulfurization”. Applied Environmental Microbiology, 7390–7393 Vol. 72,
No. 11. doi:10.1128/AEM.01474-06
12 Obeta Perpetual Oby et al
[27] Ahmadi, M.A., Zendehboudi, S., Shafiei, A., James, L.: Nonionic surfactant for
enhanced oil recovery from carbonates: adsorption kinetics and equilibrium.
Ind. Eng. Chem. Res. 51, 9894–9905 (2012. https://doi.org/10.1021/ie300269c
[28] Mallick M., Belakshe R. and Salla R. (2017): “Study of Effectiveness of
Different Surfactants for Wettability Alterations on Reservoir Rocks for
Improved Oil Recovery”. IOR NORWAY 2017 – 19th European Symposium on
Improved Oil Recovery 24-27 April 2017, Stavanger,
[29] Sunil Kumar, Tausif Ahmad, Siddharth Shankhwar, and Ajay Mandal (2019):
“Evaluation of Interfacial Properties of Aqueous Solutions of Anionic, Cationic
and Non-ionic Surfactants for Application in Enhanced Oil Recovery”. Tenside
Surfactants Detergents: Vol. 56, No. 2, pp. 138-149.
APPENDIX
Figure A1. The Effluent of Tween 80 Injection
Figure A2. The Effluent of Teepol Injection
