Fundamentals Of Wettability 344v3f

INDEX

 INTRODUCTION  OBJETIVE  FUNDAMENTALS OF WETTABILITY  THE PRACTICAL IMPORTANCE OF WETTABILITY  A PORE-LEVEL VIEW  CONCLUSIONS  BIBLIOGRAPHY

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INTRODUCTION

Understanding formation optimizing oil recovery.

wettability

is

crucial

for

The oil-versus-water wetting preference influences many aspects of reservoir performance, particularly in water flooding and enhanced oil recovery techniques. Making the assumption that a reservoir is water-wet, when it is not, can lead to irreversible reservoir damage.

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OBJETIVE

The main objective of this presentation is to understand the

basic principles of reservoir wettability, its importance, the changes that can occur and how it affects the operation of our fields.

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FUNDAMENTALS OF WETTABILITY

Wetting forces are in play all around us. 5

FUNDAMENTALS OF WETTABILITY

Forces of wetting influence hydrocarbon reservoir behavior in many ways, including: Saturation.

Multiphase flow Certain terpretation parameters

Wettability describes the preference of a solid to be in with one fluid rather than another.

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FUNDAMENTALS OF WETTABILITY

angle. An oil drop (green) surrounded by water (blue) on a water-wet surface (left) forms a bead. The angle θ is approximately zero. On an oil-wet surface (right), the drop spreads, resulting in a angle of about 180°. An intermediate-wet surface (center) also forms a bead, but the angle comes from a force balance. 7

FUNDAMENTALS OF WETTABILITY

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FUNDAMENTALS OF WETTABILITY

Wettability describes the preference of a solid to be in with one fluid rather than another. A drop of a preferentially wetting fluid will displace another fluid; at the extreme it will spread over the entire surface. Conversely, if a nonwetting fluid is dropped onto a surface already covered by the wetting fluid, it will bead up, minimizing its with the solid.

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FUNDAMENTALS OF WETTABILITY

Typically, the primary constituents of reservoirs —quartz, carbonate and dolomite— are water-wet prior to oil migration. Thus, a water-wet rock can be cleaned, dried and fully saturated with an alkane, while the surfaces in the pores remain water-wet.

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THE PRACTICAL IMPORTANCE OF WETTABILITY

During primary recovery, productivity and oil recovery.

wettability

influences

The original wettability of a formation and altered wettability during and after hydrocarbon migration influence the profile of initial water saturation, Swi, and production characteristics in the formation.

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THE PRACTICAL IMPORTANCE OF WETTABILITY

In a water-wet formation, the oil/water is above the

FWL, indicating that pressure must be applied to force oil into the largest pores.

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THE PRACTICAL IMPORTANCE OF WETTABILITY

In an oil-wet formation, the is below the FWL,

signifying that pressure must be applied to force the water phase into the largest pores.

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THE PRACTICAL IMPORTANCE OF WETTABILITY

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THE PRACTICAL IMPORTANCE OF WETTABILITY Even in a gas reservoir, wettability or its alteration can affect recovery. Condensate blockage near a wellbore decreases gas productivity.

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A PORE-LEVEL VIEW

Pore geometry complicates the application of the wetting principles discussed above. A angle is easiest to understand when the surface is a smooth plane.

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CONCLUSIONS

The Wettability is a very important determining factor for: 

Describe the behavior of fluids in the reservoir.



To analyze trends in hydrocarbon recovery.

In addition, you can modify this property at the convenience to order to increase the efficiency of production systems.

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BIBLIOGRAPHY

Wael Abdallah and Jill S. Buckley. Fundamentals of Wettability. Oilfield Review Summer 2007. Volume 19, Issue 2. Schlumberger.

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