Application of In-House Prepared Nanoparticles as Filtration Control ...

SPE 168116 Application of In-House Prepared Nanoparticles as Filtration Control Additive to Reduce Formation Damage Oscar Contreras, SPE, University of Calgary, Geir Hareland, SPE, Oklahoma State University, Maen Husein, SPE, University of Calgary; Runar Nygaard, and Mortadha Alsaba, SPE, Missouri University of Science and Technology

Copyright 2014, Society of Petroleum Engineers This paper was prepared for presentation at the SPE International Symposium and Exhibition on Formation Damage Control held in Lafayette, Louisiana, USA, 26–28 February 2014. This paper was selected for presentation by an SPE program committee following review of information contained in an abstract submitted by the author(s). Contents of the paper have not been reviewed by the Society of Petroleum Engineers and are subject to correction by the author(s). The material does not necessarily reflect any position of the Society of Petroleum Engineers, its officers, or members. Electronic reproduction, distribution, or storage of any part of this paper without the written consent of the Society of Petroleum Engineers is prohibited. Permission to reproduce in print is restricted to an abstract of not more than 300 words; illustrations may not be copied. The abstract must contain conspicuous acknowledgment of SPE copyright.

Abstract Nanoparticles (NPs) are currently being studied as a drilling fluid additives especially for application in very lowpermeability formations such as shales. Application for conventional permeable rocks is still a subject of discussion. In this work, successful application of in-house prepared iron-based nanoparticles (NP1) and calcium-based nanoparticles (NP2) to reduce filtration loss in conventional permeable media has been experimentally quantified for oil-based mud (OBM) utilizing the high-pressure high-temperature (HPHT) filter press at 500 psi and 250°F. Ceramic discs were used as the filtration medium in this application to test the performance of the NPs and glide graphite as a conventional lost circulation material (LCM) for porous media. These experiments were carried out in the presence of graphite at low and high concentrations. Filtration reduction trends were observed and a reduction up to 76% was achieved. API filter press was also used to investigate the behavior of NPs and graphite under low pressure and temperature conditions (LPLT). NP1 and NP2 at the two graphite concentrations showed a reduction up to 100%. NP1 gave higher reduction especially at low concentrations under HPHT conditions, while NP2 yielded significant reduction at high concentration under HPHT. These trends were reversed under LPLT, giving a new insight on NPs performance under different pressure and temperature conditions. At HPHT and LPLT, the effect of graphite as a filtrate reduction agent is less significant as the NPs concentration increases. High graphite level had a positive effect on filtration reduction in combination with NP1 at HPHT and LPLT. This was not the case for the blends containing NP2 at HPHT. The effect of NPs and graphite was tested individually showing a different performance compared to the combination of them. Impact of NPs and graphite on rheology was also quantified allowing identification of the more sensitive parameters in the blends. It is concluded from this study that blends containing NPs and graphite can be successfully implemented in OBM to minimize formation damage in porous media. Introduction Formation damage is an aspect considered during drilling to ensure an effective well completion (Ghalambor and Economides, 2002). It impacts on well productivity and injectivity (Bryne and Rojas, 2013) and needs to be mitigated for the conduction of a successful exploitation project. This phenomenon can occur due to either particle invasion, fines migration to the porous media, chemical precipitation, organic deposition, or pore collapse (Liu and Civan, 1994). Classic laboratory studies on formation damage (Mungan, 1965; Gray and Rex, 1966, and Muecke, 1979) concluded that particle transport, formation fines relocation and inorganic and organic precipitation are the most influential aspects in permeability reduction in consolidated formations. A later study (Liu and Civan, 1994) proposed a computer tool to study the process of formation damage focusing on macroscopic and network models. However, this work assumes an idealized wellbore, linear filtration and analysis of formation damage in laboratory which was difficult and led to limitations in the results analysis. Nowadays, industry is focused on new technologies for formation damage mitigation by preventing fluid invasion towards the porous media. For example, NPs have been recently used for such purpose (Cai et al., 2012; Zakaria et al., 2012; Srivatsa et al., 2011; Javeri et al., 2011; Sensoy et al., 2009). These very small particles can have access to the smallest pores and pore throats acting as a sealing agent in all lithology types including unconsolidated formations. Moreover, these particles can effectively interact with clays participating in the initial stage of the filter cake buildup leading to effective sealing and very

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thin filter cakes. Due to its ability of forming a thin, non-erodible and impermeable filter cake, NPs have demonstrated to be a powerful tool in reducing mud filtrate. The area to volume ratio is believed to be another reason for the effectiveness of these particles as it may provide better fluid properties at low concentrations of additives (Amanullah and Al-Abdullatif, 2010), and the rise of sponge-like clustering behavior which finds applications in completion fluids (Amanullah and Al-Tahini, 2009). Other virtues of NPs correspond to hydrodynamic properties, interaction potential with the formation (Abdo and Haneef, 2010; Amanullah et al., 2011; Srivatsa, 2010), and improved thermal conductivity generating low environmental impact, since typically the amounts implemented are lower than the commonly applied mud additives. Application of NPs in OBM was conducted by Zakaria et al. (2012) using the standard API filter press. Significant filtration reduction was reported after 30 min at LPLT. However, OBM are typically used at HPHT and therefore, results at LPLT would yield to unrealistic scenarios to be extrapolated to field conditions. This paper presents a comprehensive experimental analysis on the implementation of NPs and LCM's in OBM to reduce filtration, which started by setting up NP and LCM concentration limits. Then, NPs performance at LPLT and HPHT filtration conditions was tested and quantified. Hoelscher et al. (2012) and Friedheim et al. (2012) applied NPs to reduce fluid invasion in shales to stabilize them. This paper simulates conventional permeable formations by using 775 md ceramic discs. Drilling Fluid Characterization OBM was selected as the drilling fluid in this work. This type of mud is used broadly due to its inhibitive characteristics while drilling shale formations, low density values for applications in subpressured basins, good rheological properties at high temperatures and superior lubrication characteristics in comparison with water-based mud (WBM). The composition and rheology of the OBM used in this study is presented in Table 1. Table 1. OBM composition and rheology Oil/Water Ratio

90/10

CaCl2 Brine (30 wt% solution)

10%

Emulsifier (tall oil fatty acid)

8.0L/m3

Hydrated Lime

15-20 kg/m3

Gilsonite

5.0 kg/m3

Organophilic clay

5 kg/m3 Mud Rheology 2

PV=15 cP, YP=4 lb/100ft , Gel 10s=1.8 lb/100ft2, Gel10min=2 lb/100ft2

Nanoparticles and LCM Characterization Two different types of in-house prepared nanoparticles were investigated in this work for reduction of mud filtration. Ironbased (NP1) and calcium-based (NP2) nanoparticles were prepared in-situ at different concentrations and were then mixed with glide graphite at two concentrations. Graphite concentrations of 0.5 wt% and 2.0 wt% were selected as base concentrations following screening tests which suggested that graphite concentrations >2.0wt% yields significant precipitation while mixing. Figure 1 displays a photograph for the graphite used in this study. Table 2 presents the graphite chemical composition and Table 3 gives the graphite particle size distribution.

Figure 1. Graphite used in blends

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Table 2. Graphite chemical properties (courtesy of Bri-Chem) Carbon (LOI)

99%

Ash

1.0% max

Moisture

0.5% max

Table 3. Graphite particle size distribution (courtesy of Bri-Chem) Particle Distribution (Ro-Tap screen analysis) International ISO 565 (tbl 2): 1983 Nominal Opening mm/Microns

American ASTME (11-87) Alt. US Standard Inch/Sieve

Batch Typical % Retained on

850 micron

20

0.1

425

40

4.3

212

70

33.62

150

100

34.35

75

200

27.37

0

Pan

0.24

Rheology Analysis The rheological properties of the blends were measured at standard test temperature of 120°F. These included plastic viscosity (PV), yield point (YP), gel strength at 10 sec (10s GS) and 10 min (10min GS). Measurements were performed at two graphite levels: low and high. Most of these parameters fill within acceptable ranges, whereas the yield point deviated a little at some combination of concentrations. Table 4 presents the test matrices, which illustrates the nomenclature used to report the rheology results. Rheology results are presented in Table 5. The nomenclature “DF” is used to indicate that the blend is composed by OBM with presence of iron-based NPs. The expression “DC” stands for a blend composed of OBM and calcium-based NPs. The numbering is performed to differentiate between different concentrations; including that of graphite. Table 4. Tests matrices for rheology testing of NP1 and NP2 NP1

Graphite

0.5%

1.0%

2.5%

0.5%

DF1

DF2

DF3

2.0%

DF4

DF5

DF6

NP2

Graphite

0.5%

1.0%

2.5%

0.5%

DC1

DC2

DC3

2.0%

DC4

DC5

DC6

NP2 blends give an average increase in gel strength of around two units in comparison to the control sample at 10s and 10min. Increase of about 2 units in average on the value of plastic viscosity was experienced by NP2 blends. NP1 causes reduction in the yield point of the blends especially at high graphite concentration. Addition of graphite did not significantly impact the plastic viscosity and gel strength of the blends containing NP1. However, this is not the case for blends containing NP2, where the addition of graphite led to an increase of PV on around 4 units in comparison to the blends with low graphite content. High level of graphite was also observed to have an effect on gel strength in NP2 blends. A polymeric fatty acid having concentrations of 0.5-3.0 lb/bbl (1.4-9.0 kg/m3) or organophilic clay at concentrations of 1-6 lb/bbl (3-17 kg/m3) can be used in NP1 to improve the rheological and suspension properties. Note that the organophilic clay requires a polar additive (like water) to develop a higher yield point which may impact the NPs performance.

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Table 5. Rheology results for all blends Rheology @ 120°F Composition

PV (cP)

YP (lb/ft2)

Gel 10s (lb/100ft2)

Gel 10min (lb/100ft2)

DF1

13

3

2

23

DF2

13

0

2

22

DF3

13

1

2

23

DF4

12

0

1.8

24

DF5

13

0

2

22

DF6

13

0

1.8

22

DC1

15

3

3.5

4

DC2

14

5

3

3.5

DC3

14.5

2

3.8

4

DC4

18

5

4.2

4.6

DC5

19

6

4.5

5.2

DC6

21

5

4.8

5.9

LPLT Filtration Results Percentage of filtrate reduction under LPLT API standard test at 30 min for different concentrations of NP1 and graphite as LCM are presented in Figure 2a. The percentages were calculated based on a fluid loss of 7.0 ml at 30 min for the control sample. Three replicates were conducted per experiment and the standard deviation is shown in the figure for each point. Also, the effect of the NPs on the filtration was quantified by testing blends only containing graphite, i.e., 0 wt% of NPs. At higher concentrations of NP1, a higher filtrate reduction is obtained for the two levels of graphite. At 0 wt% NP1, the graphite level gives a filtrate reduction difference >10%. However, at concentrations larger than 1 wt% of NP1 the graphite level did not play a crucial role. It can be inferred that NP1 concentration of 1 wt% is the optimum since further addition of NPs will not have a strong impact on the performance. Results obtained at LPLT conditions for NP2 are presented in Figure 2b.

(a) (b) Figure 2. (a) Percentage of reduction in mud filtration at 30 min under LPLT for NP1. (b) Percentage of reduction in mud filtration at 30 min under LPLT for NP2 It is clear that at higher concentration of NP2, less reduction in the filtrate is obtained. Nonetheless, the positive effect of the NPs is evident when comparing the results to the case where 0 wt% NPs existed. From Figure 2 it can be concluded that as NPs concentration increases, the effect of graphite level becomes less important. In general it was observed that NP1 is superior in performance in comparison with NP2. NP2 concentration of 0.5 wt% is the optimum since further addition of NPs did not very much impact the performance. The effect of adding graphite to the blends was evaluated at the optimum concentrations (1.0 wt% for NP1 and 0.5 wt% for NP2) in an earlier research stage. Only NP1 at 1.0 wt% gives 90% of filtration reduction. NP2 at 0.5 wt% gives 31.3% of

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filtrate reduction. By looking at Figure 2 at these mentioned concentrations, it is concluded that graphite addition yields a slight improvement in filtration reduction at LPLT in combination with NPs. The filter cake after 30 min was analyzed and Figure 3 presents photographs of filter cakes collecting following LPLT measurements. Cake thickness is quoted as one important characteristic of the filter cakes. Data in Figure 3 show that just slight increase in thickness was experienced by the addition of the graphite. Figure 4 presents photos of filter cakes collected following LPLT tests in the presence and absence of NP1 and NP2. For NP1, note that in comparison to the control sample, blends containing low graphite level (DF1, DF2, and DF3) just give an average 25.3% of thickness increase. Blends containing high graphite concentration (DF4, DF5, and DF6) yield 4.7% of thickness increase in comparison to the blends containing low graphite and 31.3% with respect to the control sample. Sample Description and Thickness

Filter Cake after 30min

Control Sample (CS) 0.5±0.1mm

Graphite 0.5wt% 0.6±0.2mm


Figure 3. Filter cake characterization for control sample and blends containing graphite at low and high concentrations at LPLT NP2 blends containing low graphite level yield 33% of thickness increase in comparison to the control sample. Likewise, blends containing high graphite concentration gave 35% of thickness increase. Just a 1.5% of thickness increase was the result of going from low to high graphite concentration. Filter cake characterization allows concluding that both types of NPs are effective additives for filtration reduction in OBM only creating a slight increase in filter cake thickness which will prevent occurrence of stuck pipe. Figure 5 shows a plot of % of filter cake thickness increase with respect to the control sample vs. NPs concentration at LPLT conditions. The points are based on average filter cake thicknesses. For NP1, at both graphite levels there is an increase in thickness as concentration increases. High level of graphite yields thicker cakes. For NP2, similar to NP1 blends, the mud cake thickness increased at higher NP2 concentration. High graphite level gives a cake thickness increase, however, for NP2 blends, there is no a significant effect on cake thickness between the two graphite levels. This difference was more pronounced for NP1 blends. HPHT Filtration Results Ceramic discs, which are widely used to simulate porous media of 775 md, were utilized under HPHT conditions to evaluate the effect of NPs in reducing filtrate. A back pressure of 100 psi was used and a pressure of 600 psi was applied at the top of the pressure cell. Figure 6a summarizes the percentage of filtrate reduction when NP1 was used relative to fluid loss of 6.0 ml at 30 min obtained for the control sample. Contrary to what happened at LPLT conditions, the best filtrate reduction was obtained at the lowest NP1 concentration. This is due to the stability of NP1 at HPHT conditions. For field application purposes it is an interesting finding since it is always advisable to work under low additives concentration for economic and environmental reasons. The increase of filtrate reduction with respect to the blend containing 0 wt% of NPs was significant and this corroborates the success of the NP1 in reducing filtration. The graphite addition up to a high level of 2.0 wt% resulted beneficial for filtrate reduction especially at NP1 concentrations less than 2.5 wt%. The graphite effect is not that significant at high NP1 concentrations. NP2 results are presented in Figure 6b.

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Sample Description and Thickness



DF1

DC1

0.62±0.3mm

0.66±0.1mm

DF2

DC2

0.63±0.1mm

0.67±0.1mm

DF3

DC3

0.63±0.2mm

0.67±0.1mm

DF4

DC4

0.65±0.1mm

0.67±0.2mm

DF5

DC5

0.66±0.1mm

0.68±0.2mm

DF6

DC6

0.66±0.2mm

0.68±0.2mm


(a) (b) Figure 4. (a) Filter cake characterization for control blends containing NP1 at LPLT. (b) Filter cake characterization for control blends containing NP2 at LPLT

(a) (b) Figure 5. (a) % Filter Cake thickness increase vs. NP1 concentration at LPLT. (b) % Filter Cake thickness increase vs. NP2 concentration at LPLT

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(a) (b) Figure 6. (a) Percentage of reduction in mud filtration at 30min under HPHT for NP1. The green dot represents the blend only containing NP1 at 0.5 wt%. (b) Percentage of reduction in mud filtration at 30min under HPHT for NP2. The green dot represents the blend only containing NP2 at 2.5 wt% At HPHT conditions, NP2 work better at high concentration in contrast to what was observed at LPLT, where higher filtrate reductions were obtained at low concentrations. NP2 proved to have an effect on filtrate reduction in comparison to the case in which 0 wt% of NPs was tested. The HPHT and LPLT testing on NP1 and NP2 involved three replicates per concentration combination. For NP2, increasing the graphite concentration to 2.0 wt% resulted in a negative effect in filtration reduction. This is due to the interaction of between NP2 and graphite at HPHT, which is evident from the significant increase in the filter cake thickness as will be shown in a later discussion. Similar to the LPLT testing, as the NPs concentration is increased, the effect of the graphite concentration becomes less pronounced. NP2 at 2.5 wt% was observed to be the optimum since it gives higher filtration reduction. Overall, the performance of NP1 blends is better compared to NP2 blends at HPHT. Investigation of the individual effect of the NPs and graphite on filtration reduction was carried out at the optimum concentration for each NPs type. A blend containing NP1 at 0.5 wt%, with no graphite was tested at HPHT and the result is plotted as a green dot in Figure 6a, which shows 50% filtrate reduction. Likewise, a blend containing 2.5 wt% of NP2 was tested at HPHT resulting in the green dot on Figure 6b with a 30.9% of filtrate reduction. Figure 6a shows that 0.5 wt% of NP1 gives a higher filtrate reduction than pure graphite at both 0.5 wt% and 2.0 wt%. This confirms the superior performance of the NP1 in comparison to a conventional LCM. The blend consisting of 0.5 wt% of NP1 and 0.5 wt% of graphite is slightly improving the performance in comparison to the use of just NP1. However, the situation in which 0.5 wt% of NP1 is combined with 2.0 wt% of graphite, gives a significant improvement in filtrate reduction. It can be observed from Figure 6b that NP2 at 2.5 wt% gives a higher filtrate reduction than just graphite at both 0.5 wt% and 2.0wt%. Similarly to the situation with NP1, NP2 perform better than just conventional LCM. By combining 2.5 wt% of NP2 and 2.0 wt% of graphite, just a slightly increase in filtrate reduction is observed. When a combination of 2.0 wt% of NP2 and 0.5 wt% of graph is conducted, a significant filtrate reduction is obtained in comparison to the system containing just NP2 at 2.5 wt%. The filter cake thickness after 30 min for each experiment was characterized. Figure 7 presents the filter cake characterization for the control sample, blends containing only graphite at low and high concentrations and blends containing only NPs at the optimum concentration mentioned previously. Just a slight increase in thickness was observed by the addition of graphite while no thickness increase was experience in the blends just containing NPs. Figure 8a presents the filter cake at HPHT for the blends containing NP1. Note that in comparison to the control sample, blends containing low graphite level gave an average 6.6% of thickness increase. Blends containing high graphite concentration yield to a 9.4% of thickness increase in comparison to the blends containing low graphite and 16.6% with respect to the control sample.

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Control Sample (CS) 1.5±0.1mm



Only 0.5 wt% NP1 1.5±0.3mm

Only 2.5 wt% NP2 1.5±0.5mm

Figure 7. Filter cake characterization for control sample and blends containing graphite at low and high concentrations and blends containing just NP1 and NP2 respectively at HPHT

NP2 NPs filter cake characterization is presented in Figure 8b. Blends containing low graphite level yield to a 6.6% of thickness increase in comparison to the control sample similarly to NP1 blends. However, blends containing high graphite concentration gave a 36.6% of thickness increase. 28.1% of thickness increase is obtained by increasing graphite concentration from low to high. Compared to what happened in NP1 blends at high graphite concentration, NP2 blends at high graphite concentration give a significantly thick filter cake. This high thickness indicates the poor agglomeration of the NPs and graphite during the filtration process and therefore the performance at low graphite concentration is better when using this type of NPs. Figure 9a is a plot of % of filter cake thickness increase with respect to the control sample vs. NP1 composition at HPHT. This plot was constructed based on average filter cake thicknesses. At low graphite concentration there is no effect of NP1 concentration. At high graphite level, there is an increase on the cake thickness at higher NP1 concentration. Figure 9b shows the case for NP2. Similar to NP1 blends, at low graphite level there is no effect of NP2 concentration on filter cake thickness. However, at high graphite concentration there is a more pronounced increase in filter cake thickness. At this graphite level the cake becomes thicker as NP2 concentration increases. This significant increase in cake thickness is the reason why the filtrate is not as effective as at low graphite level at HPHT. Thicker cakes imply a less efficient filtration reduction process.

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DF1

DC1

1.6±0.3mm

1.6±0.3mm

DF2

DC2

1.6±0.3mm

1.6±0.3mm

DF3

DC3

1.6±0.4mm

1.6±0.4mm

DF4

DC4

1.7±0.3mm

2.0±0.1mm

DF5

DC5

1.75±0.5mm

2.05±0.2mm

DF6

DC6

1.8±0.2mm

2.1±0.2mm


(a) (b) Figure 8. (a) Filter cake characterization for control blends containing NP1 at HPHT. (b) Filter cake characterization for control blends containing NP2 at HPHT

(a) (b) Figure 9. (a) % Filter Cake thickness increase vs. NP1 concentration at HPHT. (b) % Filter Cake thickness increase vs. NP2 concentration at HPHT

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This mud cake characterization in a porous media shed a light on the utilization of these NPs types during drilling operations using OBM. Figure 10 shows a cross-section of a ceramic disc after testing of blend DF3. Note that the fluid invasion cannot be easily observed just by looking at the ceramic disc cross-section.

Figure 10. Cross-section of ceramic disc after DF3 blend testing at HPHT

Conclusions The experimental research conducted in this paper proved the successful application of NPs and LCM in reducing mud filtration in porous media using OBM. These findings are anticipated to be of significant impact in drilling operations to mitigate the formation damage due to fluid invasion. The most remarkable conclusions are: - NP1 and NP2 proved to be a successful agent in plugging the porous media simulated by ceramic discs under HPHT conditions - NP1 and NP2 can yield to significant filtrate reduction under LPLT conditions. Better results are obtained at higher graphite concentration at these conditions. Filter cake thicknesses behaved under an acceptable range - NPs proved to be superior than the graphite as a filtrate reduction agent - For HPHT and LPLT conditions, the impact of graphite concentration in filtration is less pronounced as the NPs concentration is increased - At HPHT, NP1 work more efficiently at lower NPs concentrations in contrast to the case under LPLT where higher filtrate reduction was experienced at higher NPs concentrations. NP2 give better filtrate reduction at higher NPs concentrations. At LPLT, NP2 performed reasonably better at low NPs concentrations - High graphite level had a positive effect in filtration reduction in combination with NP1 at HPHT and LPLT. In blends containing NP2 at HPHT, low graphite level worked more efficiently due to the thick cakes formed at high graphite concentration. - Rheology measured at 120 °F is not significantly affected by the addition of NPs and LCM. This allows NPs to be included without requiring additional rheological additives. Acknowledgements The authors would like to thank Talisman Energy, Pason Systems Corporation, the Natural Sciences and Engineering Research Council of Canada (NSERC) for supporting this research. References Abdo, J. and Haneef, D. 2010. Nanoparticles: Promising Solution to Overcome Stern Drilling Problems. NSTI-Nanotech Vol 3: 635-638. Ammanullah, M., and Al-Abdullatif, Z. 2010. Preliminary test results of a water based nanofluid. The 8th International Conf. and Exhibition on Chemistry Industry, Manama, Bahrain, 18-20 October. Ammanullah, M., Al-Arfaj, M.K., and Al-Abdullatif, Z. 2011. Preliminary Test Results of Nano-based Drilling Fluids for Oil and Gas Field Applications. Paper SPE 139534 presented at the SPE/IADC Drilling Conference and Exhibition, Amsterdam, The Netherlands, 1-3 March. http://dx.doi.org/10.2118/139534-MS. Amanullah, M., and Al-Tahini, M.A. 2009. Nano-Technology-Its Significance in Smart Fluid Development for Oil and Gas Field Application. Paper SPE 126102 presented at the 2009 Saudi Arabia Section Technical Symposium and Exhibition, Alkhobar, Saudi Arabia, 09-11 May. http://dx.doi.org/10.2118/126102-MS. Bryne, M., and Rojas, E. 2013. Formation Damage Matters, Sometimes – Quantification of Damage Using Detailed Numerical Modeling. Paper SPE 165115-MS presented at the 10th SPE International Conference and Exhibition on European Formation Damage, 5-7 June. http://dx.doi.org/10.2118/165115-MS.

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Cai, J., Chenevert, M.E., Sharma, M.M., and Friedheim, J. 2012. Decreasing Water Invasion into Atoka Shale Using Nanomodified Silica Nanoparticles. SPE Drilling and Completion 27 (1): 109-112. SPE 146979-PA. http://dx.doi.org/10.2118/146979-PA. Friedheim, J., Young, S., De Stefano, G., Lee, J., Guo, Q. 2012. Nanotechnology for Oilfield Applications – Hype or Reality?. Paper SPE 157032 presented at the SPE International Oilfield Nanotechnology Conference and Exhibition held in Noordwijk, The Netherlands, 12-14 June. http://dx.doi.org/10.2118/157032-MS. Ghalambor, A., and Economides M.J. 2002. Formation Damage Abatement: A Quarter-Century Perspective. SPE Journal 7 (1): 4-13. SPE 77304-PA. http://dx.doi.org/10.2118/77304-PA. Gray, D.H., and Rex, R.W. 1966. Formation Damage in Sandstones Caused by Clay Dispersion and Migration. Presented at 14th Natl. Conference on Clays and Clays Minerals: 355-66. Hoelscher, K.P., De Stefano, G., Riley, M., Young, S. 2012. Application of Nanotechnology in Drilling Fluids. Paper SPE 157031 presented at the SPE International Oilfield Nanotechnology Conference and Exhibition held in Noordwijk, The Netherlands, 12-14 June. http://dx.doi.org/10.2118/157031-MS. Javeri, S.M., Haindade, Z.W., Jere, C.B.2011. Mitigating Loss Circulation and Differential Sticking Problems using Silicon Nanoparticles. Paper SPE/IADC 145840 presented at the 2011 SPE/IADC Middle East Drilling Technology Conference and Exhibition held in Muscat, Oman 24-26 October. http://dx.doi.org/10.2118/145840-MS. Liu, X., and Civan, F. 1994. Formation Damage and Skin Factor Due to Filter Cake Formation and Fines Migration in the Near-Wellbore Region. Paper SPE 27364-MS presented at the SPE Formation Damage Control Symposium, 7-10 February. http://dx.doi.org/10.2118/27364-MS. Muecke, T.W. 1979. Formation Fines and Factors Controlling Their Movement in Porous Media. J. Pet. Tech.: 144-50. Mungan, N. 1965. Permeability Reduction through Changes in PH and Salinity. J. Pet. Tech.: 1449-53. Sensoy, T., Chenevert, M.E., Sharma, M.M. 2009. Minimizing Water Invasion in Shale Using Nanoparticles. Paper SPE 124429 presented at the 2009 SPE Annual Technical Conference and Exhibition held in New Orleans, Louisiana, 4-7 October. http://dx.doi.org/10.2118/124429-MS. Srivatsa, J.T. 2010. An Experimental Investigation on use of Nanoparticles as Fluid Loss Additives in a Surfactant – Polymer Based Drilling Fluid. M.S. Thesis at Texas Tech University. Srivatsa, J.T., and Ziaja, M.B. 2011. An Experimental Investigation on use of Nanoparticles as Fluid Loss Additives in a Surfactant – Polymer Based Drilling Fluids. Paper IPTC 14952 presented at the International Petroleum Technology Conference held in Bangkok, Thailand, 7-9 February. http://dx.doi.org/10.2523/14952-MS. Zakaria, M.F., Husein, M., Hareland, G. 2012. Novel Nanoparticle-Base Drilling Fluid with Improved Characteristics. Paper SPE 156992 presented at the SPE International Oilfield Nanotechnology Conference held in Noordwijk, The Netherlands, 12-14 June. http://dx.doi.org/10.2118/156992-MS.