LABORATORY REPORT
PETROLEUM ENGINEERING LABORATORY VI (EG 322)
NUMBER OF EXPERIMENT: 4
EXPERIMENT TITLE: CONTACT ANGLE MEASUREMENT USING IMAGING
METHOD
LAB SESSION/GROUP NUMBER: WEDNESDAY /GROUP1
STUDENT NAME: SATTISH SOMUNAIDU
STUDENT ID:1001645032
TUTOR’S NAME: MS NOOR A’SHIQIN BINTI JAAFAR @ MUSTAFA
DATE OF EXPERIMENT :20/02/2019
DATE OF SUBMISSION :27/02/2019
UCSI UNIVERSITY
FACULTY OF ENGINEERING
Table of content
No
Content
Page
1.
Introduction
3
2.
Objective
4
3.
Material and apparatus
4
4.
Procedure
4
5.
Results and Calculation
5
6.
Discussion
5-6
7.
Conclusion
6
8.
References
7
9.
Raw data
8
2
INTRODUCTION
The wettability of a formation determines the irreducible water saturation in the reservoir. It
determined how easily a fluid moves and had tremendous impact for optimizing oil recovery.
The oil versus-water wetting preference influences many aspects of reservoir performance,
particularly in water flooding and enhanced oil recovery techniques. Wetting has gotten huge
enthusiasm from both crucial and connected perspectives. It plays an essential job in
numerous mechanical procedures, for example, oil recuperation, oil, fluid covering, printing,
and shower extinguishing. Wettability thinks about normally include the estimation of contact
angles as the essential information, which demonstrates the level of wetting when a strong
and fluid communicate. Little contact angles (90°) compare to high wettability, while large
contact angles (90°) relate to low wettability. Presentation of the crucial science behind
wetting and contact edge marvels, trailed by an exhaustive portrayal of the different systems
used to quantify contact angles, just as their application and constraints as far as the
geometric types of strong examples.
Wettability in Reservoirs
Reservoir rocks are complex structures, often comprising a variety of mineral types. Each
mineral may have a different wettability, making the wetting character of the composite rock
difficult to describe. Generally, most of the reservoirs where the primary constituents are
quartz, carbonate and dolomite are water-wet prior to oil migration. However, the conditions
may be altered by components of the crude oil to become oil-wet. As different types of
wettability exhibit different production performances, a water-wet reservoir system is
desirable for an efficient oil transport compared to an oil-wet reservoir.
Measurement of Wettability
When an interface exists between a liquid and a solid, the angle between the surface of the
liquid and outline of the contact surface is described as the contact angle (°). The contact
angle (wetting angle) is a measure of the wettability of a solid by a liquid. If the observed
angle between the surface and the slope of the droplet is lower than 90°, the rock is
considered water-wet. If the observed angle is larger than 90°, the rock is considered oil-wet.
Figure 1: Differentiation between water-wet and oil-wet
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Objective



To differentiate between water-wet and oil-wet condition.
To describe the factors affecting wettability.
To identify the wettability between the interface of a solid and liquid by measuring
the contact angle between a liquid and a solid
Apparatus
1. Phoenix 150 contact angle analyzer
2. 1 mL syringe
3. Clean cotton swabs
Materials
1. Crude oil.
2. Cooking oil
3. Distilled water
4. Toluene
5. Ethanol
6. Used Engine Oil
Procedures
1. Surfaceware7 program were started.
2. The glass flat on the stage placed
3. The syringe position were adjusted so that the bottom of the needle appears about a fourth
of a way down in the live window screen.
4. The baseline were adjusted to be horizontal and about just below the midpoint in the live
window screen.
5. one drop of crude oil was carefully applied onto the solid surface with a syringe by moving
4μL.
6. The syringe needle lowered slowly using the thumbscrew on the syringe fixture until the
drop comes in contact with the stage.
7. “Measure” in the main menu bar and then “Take a Picture” were clicked.
8. “CA Tools” and then on “Contact Angle” were clicked to open the contact angle tool.
9. The green vertical line adjusted by simply clicking on the window screen to the left of the
drop. Avoided the touching of the drop and assured that there is a small space between the
line and the drop. The yellow line positioned to the right of the drop where it is not touching
it or the wall of the application window.
10. Clicked “Option” in “Contact Angle” window menu bar to set the “Time Interval” (in
seconds) and “Number of Measurement” desired.
Select:
Number of Measurement = 60
Time Interval = 2000
11. In the “Contact Angle” window, the “Start” button were clicked, then the vertical
adjusted line so that it passes through the center of the drop.
12. “Measure” clicked.
13.This experiment is repeated with other samples.
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Result
No
Material
First Reading of
contact angle (°)
1.
2.
3.
4.
5.
6.
Crude oil
Cooking oil
Distilled Water
Ethanol
Toluene
Used Engine Oil
17.41
13.97
31.37
12.94
11.53
12.27
Second Reading
of contact angle
(°)
14.52
13.25
26.19
13.07
12.81
12.76
Third Reading
of contact angle
(°)
13.39
11.27
30.56
12.99
14.89
11.59
Average
Contact
Angle (°)
15.11
12.83
29.37
13.00
13.08
12.21
Calculation
Average Contact Angle: First Reading + Second Reading+ Third Reading/ 3
Discussion
1. Explain the differences observed in the contact angles for the different materials.
Contact angle can be taken as a proportion of wettability of a strong by fluid. It is an essential
factor to be considered as a sign of how great/awful a liquid spreads over a strong surface.
The figure underneath shows 3 distinct beads conduct on a surface. The most left has a high
contact angle what's more, does not spread over the surface. This conduct is known as nonwetting liquid and is hydrophobic. Then again, the centre liquid spreads well over the surface
and has little contact angle, and known to be great wetting liquid and is hydrophilic. In
petroleum system, contact angle can be an indication of fluid (oil, gas, water) behaviour
inside formation rock during production phase. In the formation, water-wet system is
desirable so that oil can move easily through the rock. Since water sticks on the formation
rock, oil droplets will not stick to the formation and the flow will not be hindered.
Figure 2: Contact Angle
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From the experiment, we were able to observe different average contact angle possessed by
various fluids when in contact with common solid surface, glass plate. The measurement is
able to provide a good indication to tell whether it is a good wetting or bad wetting fluid. The
experiment was first carried out with distilled water, and the average contact angle was taken
to be 29.37°. The following fluid tested was light crude oil, with lower average contact angle
of 15.11° and finally used engine oil with reading of 12.21°. The normal contact angle of
distilled water is outstandingly more prominent than the rest of the liquids, as appeared with
the higher angle of curvature when the water is in contact with the glass plate. This
demonstrates distilled water does not spread well superficially contrasted with the other 2
liquids and has lower wettability contrasted with both. Then again, engine oil and crude oil
have comparative contact angle and has better wettability contrasted with water.
2. What do low values of contact angle suggest about a liquid and its interaction with a
surface?
Proceeding with the discussion above, the perception on little contact angle in used engine oil
and light crude oil demonstrates that they tend to follow on the solid surface. At the end of
the day, used engine oil and light crude oil have a more grounded solid-liquid collaboration
when contrasted with distilled water. Used engine oil has the littlest contact angle (15.11°)
and consequently have the most grounded solid-liquid communication what's more, can
without much of a stretch spread on solid surface. This phenomenon could also be described
as cohesion and adhesion. Cohesion refers to ability of fluid to attract one another while
adhesion is the interaction between different substance, in this case liquid and fluid. In case
of light crude oil, it has high adhesive force compared to cohesive force.
3. Describe a real-world example of a readily observable liquid-solid interaction and
explain the rationale with regard to the reservoir condition.
One genuine model on liquid-solid cooperation is the arrangement of water beads on certain
leaves. The development of water beads demonstrates high contact angle among water and
leaves' surface, demonstrating low wettability. Liquid-solid association among water and
leaves is feeble, subsequently water can't spread effectively superficially. The outside of the
leaves is made out of a material that does not enable water to spread on effectively. Relating
this condition, water-wet store does not permit oil beads to adhere to the arrangement
effectively. Water-wet repository implies that water have higher wettability to the
development shake and covers the little pores in the stone. Subsequently, oil have littler
wettability and does not stick on the stone development, which is a good condition in the
supply as oil can stream effectively through the development matric and won't stall out in the
arrangement.
Conclusion
Based on the result of this experiment, the angle determined for wettability of crude oil,
distilled water, toluene, cooking oil, ethanol and used engine oil as follows 15.11°, 29.37° and
13.08°,12.83°, 13.00° and 12.21°. It can be concluding that distilled water has high wettability
and strong interaction between solid and liquid. In this experiment the used engine oil
wettability angle is 12.21° (less than 90°), oils are still in the low wettability group.
Differentiation between water-wet and oil-wet condition were differentiated. In addition,
factors affecting wettability also were explained. Objectives of this experiment were met.
6
References
1. Contact angle. (2019, February 10). Retrieved from
https://en.wikipedia.org/wiki/Contact_angle
2. (n.d.). Retrieved from https://www.spec2000.net/09-wettability.htm
3. Schlumberger. 2017. Water-Wet. Retrieved from:
http://www.glossary.oilfield.slb.com/Terms/w/water-wet.aspx
4. ZISMAN, W. A. (1964). Relation of the Equilibrium Contact Angle to Liquid and
Solid Constitution, 1–51. https://doi.org/10.1021/ba-1964-0043.ch001
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