Nano technology has applications in enhanced oil recovery by improving characterization of reservoirs, completing other EOR methods, and changing reservoir properties with nanofluids. Nano-sensors and analysis can better characterize rocks and fluids at micro-scales. Nanoparticles can flow into small pore throats and increase interface areas to more easily alter wettability and fluid properties. Several case studies showed nanofluids improved oil recovery over waterflooding, including one that recovered 67% of oil compared to 36% for waterflooding. Fine migration can also be addressed using nanoparticles to coat surfaces and stabilize fines.

1. Applications of Nano technology in
enhanced oil recovery
Professor: Dr. sedaee
Mahdi shahbazi,hossein mokhlesi
winter 2017
IN THE NAME OF GOD

2. Nano technology
Nanotechnology ("nanotech") is manipulation of matter on an
atomic, molecular, and super molecular scale. The earliest, widespread
description of nanotechnology referred to the particular technological goal of
precisely manipulating atoms and molecules for fabrication of macro scale
products, also now referred to as molecular nanotechnology.
Nanotechnology as defined by size is naturally very broad, including fields of
science as diverse as surface science, organic chemistry, molecular biology,
semiconductor physics, micro fabrication, molecular engineering, etc.

3. Nano technology a new solutions to
old challenges
Enhanced Oil Recovery techniques are gaining more attention
worldwide as the proved oil reserves are declining and the oil price is
hiking. Although many giant oil reservoirs in the world were already
screened for EOR processes, the main challenges such as low sweep
efficiency, costly techniques, possible formation damages,
transportation of huge amounts of EOR agents to the fields especially
for offshore cases, analyzing micro-scale multi-phase flow in the rock
to the large scale tests and the lack of analyzing tools in traditional
experimental works, hinder the proposed EOR processes.

4. Nano in EOR
Nano can be named one of the new science in oil industry. One of the
major characteristics of Nano-technology is the ability to combine it
with other methods of EOR. Generally it can be said Nano technology
refers to the ability to complete and fix the weakness of the old ways
and discover the new mechanisms for EOR to continue the way.

5. Applications of Nano
As mentioned previously Nano can use to develop new techniques and
completed the old method.so we can divide the applications of Nano-
technology to there principal group:
• Using from Nano to characterizing reservoir
• Using Nano to complete other methods
• Using from Nanofluid to change reservoir characterizes

6. Nano to characterizing reservoir
Nano-sensors: Very complicated types of fluids and rock structure
persuaded the scientists to provide reservoir engineers with sensors
installed in the wells monitoring flow regimes, fluid composition and
reservoir properties. Besides, there are several types of tools to be used
in the reservoir for scanning, logging and testing the rock, fluid as well
as reservoir condition to find the optimized production scenario for
higher production rate and better recovery efficiency. All the well bore
sensors and monitoring tools are large enough that need preparing
extra space for them in the well opening, therefore they can hardly
monitor far beyond the well location which is very tiny compared to the
reservoir volume.

7. Nano to characterizing reservoir
Using Nano-scale sensors will give the engineers the chance to:
• Trace the trapped oil, its saturation, location with respect to the pore
spaces and associated forces need to recover it for EOR.
• Monitor the rock openings in micro-scale to have digital maps of the pore-
throat network for modeling the injecting/producing fluids.
• Assessing in depth heterogeneities especially for vuggy and fractured
reservoirs.
• Checking the boundaries, fluids contacts, connectivity with neighboring
reservoirs to make an accurate 3D/4D seismic view of the formation which
enhance the understanding for any EOR activities.
• Checking the success of remediation technique if any. The remedies have
been used during many EOR processes such as selective plugging and
water shutoff. Nanotechnology through Nano scale sensors could be
utilized to check if it has been successfully employed or not.

8. Nano to characterizing reservoir
Nano-Analysis: The analytical equipment's available in the field of
nanotechnology to analyze the surface changes such as Atomic Force
Microscopy (AFM) and X-Ray Photo Spectroscopy (XRP), Raman
Spectroscopy, Zeta Potential meter; scanning tools such as Scanning
Electron Microscopy (SEM), Micro and Nano CT scanners are very
useful tools in assessing the structure of porous media, wettability
alteration and many other investigations in this field that needs very
accurate measurement in Nano-scale changes inside the porous media
and at the fluid-fluid/fluids-solid interfaces. Professional expertise's are
needed first to use these equipment's then to mimic the reservoir
condition in the lab to be analyzed through these techniques.

9. Nano to complete other methods

10. Nano to complete other methods
Nano-scale movement in micro size porous media: The most
important challenges to traditional EOR processes are the transfer of injected
components into porous media as the pore throats could be plugged causing
permeability reduction and increasing the cost of injection. Since the Nano-
scale components are usually in the order of 100-50nm, can easily flow into
the rock pore structure which is usually greater than 10 micron. Dust injection
is the well known form of nanoparticles injected into the oil saturated
formation to perform a variety of changes from fluid properties to interfacial
changes both for fluid-fluid and fluids-solid interfaces.

11. Nano to complete other methods
Very high specific surface area of nanoparticles: This is the most
notable property for enhanced mass transfer between the phases and
changing fluid properties more easily and at lower costs, homogenously
distributed in porous media, adsorbed on the rock surface to change the
wettability and changing the thermal conductivity of the fluids and the rock.

12. Nano to complete other methods
Chemicals disadvantage: Surfactants can also reduce the IFT to
an ultra low value. However, surfactants are not stable under
harsh reservoir conditions, and the loss rate of surfactant during
waterflooding is quite high. Large quantities are required for
effective recovery and the transportation of the chemicals to the
oil fields is expensive so Nano particles can be a good candidate
to Bested the chemical methods.

13. Nano in WAG
nanoparticles were added to the water phase of water alternating gas (WAG)
and injected into water flood residual oil in two dimensional glass micro
models to study the effect of the nanoparticles qualitatively at low pressures.
Silicon oxide (SiO2) and aluminum oxide (Al2O3) nanoparticles, at different
concentrations.

14. Nano in WAG

15. Nano in WAG

16. Nano in WAG

17. Nanofluid to change reservoir
characterizes
The main reason for choosing Nano its presence in areas where other
methods have no ability to do it. At the next slide we see a table that show
the EOR method against property that need to change.
The table show that Nano technology is the best choose were the other
method can’t use or have not good oil recovery such as low permeability,
high salinity or hardness,….

18. Nanofluid to change reservoir
characterizes

19. Nanofluid to change reservoir
characterizes
Nanofluid can use to change property’s of reservoir such as:
• Fluid-fluid properties: interfacial tension, viscosity
• fluid-rock properties: contact angle, relative permeability
• Thermal conductivity of injection fluid

20. Case I(Egypt)
El-Diasty and Salem, 2013 investigated using Nanosilica particles on real
Egyptian formation to compare between using waterflooding and Nanofluid
flooding as EOR methods. As shown in next slide, it is obvious that using
water flooding to displace the oil in place recovered 36% of IOIP at the
breakthrough point while the Nanofluid flooding recovered 67% of IOIP at
the breakthrough point. This is an evidence for the ability of the Nanofluid to
displace the oil better than the water.

21. Case I

22. Case II(Nigeria)
Some selected types of nanoparticles that are likely to be used include oxides
of Aluminum, Zinc, Magnesium, Iron, Zirconium, Nickel, Tin and Silicon. These
nanoparticles were used to conduct EOR experiments under surface
conditions. The first involved displacing the injected oil with the Nanofluids. In
the second case, the sands were soaked in Nanofluids for 60 days before oil
was injected into the system and displaced with low salinity brine

23. Case II

24. Case II

25. Case II
Conclusions
The conclusions made after this study are:
1.Aluminium oxide nanoparticles dispersed in brine and distilled water have the tendency to improve
oil recovery through reduction of oil viscosity.
2.Silane treated Silicon oxide and hydrophobic Silicon oxide dispersed in ethanol have the tendency
to improve oil recovery through change of rock wettability. Ethanol when used alone (without
nanoparticles) also enhances oil recovery by reduction of interfacial tension between oil and water.
3.The type of fluid used for nanoparticle dispersion in sands to improve oil recovery is important
because it plays a significant role in the process.
4.Magnesium oxide and Zinc oxide in distilled water and in brine result in permeability problems.
Recovery from the use of Magnesium oxide for EOR is very poor.
5.Comparing the efficiency of different fluids(without nanoparticles in them) in displacing oil from
sands generally, It can be seen that distilled water gives low recovery, brine gives good recovery,
ethanol gives good recovery while the effect of diesel appears good.
6. Caution should be used when using nanoparticles dispersed in brine and ethanol for EOR or for
solving other problems in the formation because most of these nanoparticles can impact negatively
on oil recovery.

26. Case III(Berea sandstone)
In this study Low-permeability water-wet Berea sandstones core-plugs with
porosity ranged 13-15% and permeability ranged 5-20 mD were tested.
A hydrophilic silica nanoparticles with primary particle size 7 nm was
employed without surface treatment. Nanofluids with various concentration
ranged 0.01 - 0.1 wt.% were synthesized with synthetic saline water for
optimizing study. The wettability alteration due to Nanofluids was observed;
coreflood experiment was conducted and compared its displacement
efficiency.

27. Case III

28. Case III

29. Case III

30. Case III
The results observed a range of Nanofluids concentration that could
maximize oil recovery in low-permeability water-wet Berea sandstone.
Although contact angle of aqueous phase decreases as Nanofluids
concentration increase which means easier of oil to be released but we
observed that higher concentration (e.g. 0.1 wt.%) has a tendency to block
pore network and will decrease or even without additional oil recovery

31. Fine migration a new idea
Formation damage due to fine migration is one of destructive side-effects of some EOR
techniques which may also find solutions from Nanotechnological viewpoints. Fines loosely
attached to the pore surface are in the equilibrium with the pore fluids. These particles start to
flow when the equilibrium state is disturbed by the EOR agent which, may end up in permeability
reduction in porous media. Different solutions have been suggested to prevent detachment of
fines from surface such as ionic clay stabilizer, polymers and resins. Nanofluids containing metal
oxide nanoparticles show specific properties.
Nanofluids that contain nanoparticles (MgO, Sio2, and Al2O3) show specific properties such as
high tendency for adsorption and good candidate for the injection into the near wellbore regions
because of their very small sizes. Hence the study of interactions between fines and pore surfaces
and investigating the governing forces are important issues to describe the mechanism of this
process. The main types of these forces are electric double layer repulsion and London-van der
Waals attraction. It is possible to change these forces by the use of nanoparticles as surface
coatings. Nanoparticles increase the effect of attraction forces in comparison with repulsion
forces. Based on extensive experimental works, the magnitude of the electric double layer
repulsion in comparison with the London-van der Waals attraction between fines and media grain
particles was considerably diminished when MgO nanoparticle was used to coat the porous
media resulting in fine fixation.

32. Sources:
 Luky Hendraningrat, Shidong Li and Ole Torsæter “Enhancing Oil Recovery of Low-
Permeability Berea Sandstone through Optimized Nanofluids Concentration “ July
2013
 Abdelrahman Ibrahim El-Diasty” Applications of Nanotechnology in the Oil & Gas
Industry: Latest Trends Worldwide & Future Challenges in Egypt “April 2013
 A. Khezrnejad, L.A. James, and T.E. Johansen” Water Enhancement Using
Nanoparticles in Water Alternating Gas (WAG) Micromodel Experiments” 2014
 N.A. Ogolo, O.A. Olafuyi, and M.O. Onyekonwu” Enhanced Oil Recovery Using
Nanoparticles”April 2014
 Shahab Ayatollahi, Mohammad M. Zerafat” Nanotechnology-Assisted EOR
Techniques: New Solutions to Old Challenges “June 2012
 A.J.P. Fletcher, Parr Systems Pty. Ltd., and J.P. Davis” How EOR Can be Transformed
by Nanotechnology “April 2010
 Mohamed Haroun, Saeed Al Hassan, Arsalan Ansari, Nabeela Al Kindy, Nada Abou
Sayed, Basma Ali, Hemanta Sarma” Smart Nano-EOR Process for Abu Dhabi
Carbonate Reservoirs “November 2012