drilling and petroleum

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MINI PROJECT REPORT
ON
FLUID LOSS ADDITIVE IN WATER BASED MUD
Submitted by
P. DHARUN RAJ (APE20001)
BACHELOR OF ENGINEERING
IN
PETROLEUM ENGINEERING
Under the Guidance of
Mr.A.Jayasekaran
Visiting Faculty of AMET University

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DEPARTMENT OF PETROLEUM ENGINEERING
BONAFIDE CERTIFICATE
Certified that this Mini Project report entitled “ FLUID LOSS ADDITIVE
IN WATER BASED MUD” is the Bonafide work of P.DHARUN RAJ
(APE20001), for the award of Degree of Bachelor of Engineering in Petroleum
Engineering, carried out under my guidance and supervision.
Date:
Place: Signature of
Guide
Date:
Place: Signature & seal of
HOD

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ACKNOWLEDGEMENT
We are privileged to thank Dr.A.Rajesh Kanna, Assistant Professor and
Head of the Department of Petroleum Engineering, AMET University for his
immense help, valuable Guidance and encouragement, which pay our effort in
bringing this project to a successful completion.
We thank our project guide Mr.A.Jayasekaran, Visiting Professor,
Department of Petroleum Engineering, AMET University for guiding us
throughout this project, for his continuous support and motivation throughout the
course of the project work.
Further we would like to take this opportunity to thank all the Teaching Staffs of
Department of Petroleum Engineering for their timely help and assistance during
the course of this project.
P. DHARUN RAJ
(APE20001)

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ABSTRACT
This work is based on the locally sourced rich gourd cellulose for improvement
of rheological properties of water based mud. The efficiency of the operation is
enhanced by the application of drilling fluid. The mud samples were formulated
in the absence and presence of various concentrations of rich gourd cellulose. The
results obtained were compared with that of a standard, mud formulated from
Polyanionic cellulose (PAC). The results shows that the pH, mud density, specific
gravity of the mud formulated from rich gourd cellulose were higher than that of
the standard mud.
The results show that cellulose from rich gourd can significantly reduce fluid
loss control agent. This suggests that cellulose processed from Rich gourd
cellulose is a better fluid loss control agent than poly-anionic cellulose (PAC) in
the preparation of drilling mud .Invasion of fluids into porous media during
drilling can lead to irreparable damage and reduced well productivity.
Minimizing formation damage, enhancing well productivity and saving cost
will thus depend on the introduction of less invasive fluid formulations.
In this study four different mud formulations were prepared to investigate
the effect of rich gourd loofah on rheological properties of mud.
These fluid properties were determined according to API standard.
Statistical analyses showed that adding Cellulose could successfully enhance
the rheological behavior of the mud. Moreover, the formulation containing
cellulose increased viscosity up to almost two times. Gel strength and
viscosity also increased overtime.

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TABLE OF CONTENTS
S.NO TITLE PAGE NO
1 INTRODUCTION 7
2 CELLULOSE 13
2.1 Preparation of cellulose
2.2 Extraction of cellulose
2.3 Limitations
2.4 Result
3 PREPARATION OF MUD 17
3.1 Mud Preparation
3.2 Determination of Mud Density
3.2.1 Calibration
3.2.2 Procedure
3.4 Rheology
3.4.1 Rheometer
4 CONCULSION 25
5 RECOMMENDATION 26
6 REFERENCE 27

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LIST OF FIGURES
FIGURE NO TITLE PAGE NO
1) XRD Results of the Experimental Cellulose- 16
(Rich Gourd Loofah)
2) Graphical values of 2% rich gourd loofah 21
3) Graphical values of 4% rich gourd loofah 22
4) Graphical values of 6% rich gourd loofah 23
5) Graphical values of without PAC 24
LIST OF TABLES
TABLE NO TITLE PAGE NO
I. MUD PROPERTIES OF SAMPLE A, B AND C 20

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CHAPTER I
Introduction:
Drilling the wellbore is the first and the most expensive step in the oil and gas
industry. Expenditures for drilling represents 25% of the total oil field
exploitation cost and are concentrated mostly in exploration and development of
well drilling. Drilling fluids, which represent about one fifth (15-18%) of the total
cost of petroleum well drilling, must generally comply with three important
requirements – they should be easy to use, not too expensive and environmentally
friendly. the complex drilling fluid plays several functions simultaneously. It is
the single component of the well-construction process that remains in contact
with the wellbore throughout the entire drilling operation. Drilling-fluid systems
are designed and formulated to perform efficiently under expected wellbore
conditions.
Functions:
 Remove cuttings from well
 Suspend and release cuttings
 Control formation pressure
 Seal permeable formations
 Maintain wellbore stability
 Minimizing formation damage
 Cool, lubricate, and support the bit and drilling assembly
 Transmit hydraulic energy to tools and bit
 Ensure adequate formation evaluation
 Control corrosion
 Facilitate cementing and completion
 Minimize impact on environment

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Classification:
Many types of drilling fluids are used on a day-to-day basis. Some wells require
that different types or some types be used in combination with others.
The various types of fluid generally fall into a few broad categories:
Air: Compressed air is pumped either down the bore hole's annular space or down
the drill string itself.
Air/water: The same as above, with water added to increase viscosity, flush the
hole, provide more cooling, and/or to control dust.
Air/polymer: A specially formulated chemical, most often referred to as a type
of polymer, is added to the water & air mixture to create specific conditions. A
foaming agent is a good example of a polymer.
Water: Water by itself is sometimes used. In offshore drilling sea water is
typically used while drilling the top section of the hole.
Water-based mud(WBM): Most basic water-based mud systems begin with
water, then clays and other chemicals are incorporated into the water to create a
homogeneous blend resembling something between chocolate milk and a malt
(depending on viscosity). The clay is usually a combination of native clays that
are suspended in the fluid while drilling, or specific types of clay that are
processed and sold as additives for the WBM system. The most common of these
is bentonite, frequently referred to in the oilfield as "gel". Gel likely makes
reference to the fact that while the fluid is being pumped, it can be very thin and
free-flowing (like chocolate milk), though when pumping is stopped, the static
fluid builds a "gel" structure that resists flow. When an adequate pumping force
is applied to "break the gel", flow resumes and the fluid returns to its previously
free-flowing state. Many other chemicals (e.g.,Potassium formate) are added to a
WBM system to achieve various effects, including: viscosity control, shale

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stability, enhance drilling rate of penetration, cooling and lubricating of
equipment.
Oil-based mud (OBM): Oil-based mud is a mud where the base fluid is a
petroleum product such as diesel fuel. Oil-based muds are used for many reasons,
including increased lubricity, enhanced shale inhibition, and greater cleaning
abilities with less viscosity. Oil-based muds also withstand greater heat without
breaking down. The use of oil-based muds has special considerations, including
cost, environmental considerations such as disposal of cuttings in an appropriate
place, and the exploratory disadvantages of using oil-based mud, especially in
wildcat wells. Using an oil-based mud interferes with the geochemical analysis
of cuttings and cores and with the determination of API gravity because the base
fluid cannot be distinguished from oil returned from the formation.
Synthetic-based fluid (SBM): (Otherwise known as Low Toxicity Oil Based
Mud or LTOBM): Synthetic-based fluid is a mud where the base fluid is a
synthetic oil. This is most often used on offshore rigs because it has the properties
of an oil-based mud, but the toxicity of the fluid fumes are much less than an oil-
based fluid. This is important when men work with the fluid in an enclosed space
such as an offshore drilling rig. Synthetic-based fluid poses the same
environmental and analysis problems as oil-based fluid.

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Advantages:
 The water based drilling mud helps in improving the rheology.
 Key reason for wellbore stablity and maintaining the temperature.
 The drilling efficency using these type of mud is good.
 It has good rate of penetration .
 It is enivormental friendly and easy to dispose.
 It is economically compared with other based fluids.
 It helps in inhibition issues with formation.
 It helps to lubricate the downhole tools while drilling.
 It seals the formation and prevent the influx of fluids.
 Easy to handle the mud.
 The filteration of mud is easy compared to other fluids filteration.
Disadvantages:
 Water-based mud can swell shale formation, a brittle mineral, collapse
boreholes and impact drilling outcome in the drilling operations
 Gases produced among shale cracks whose non-organic part is possibly
aqueous wetting phase can be easily displaced by water, offsetting the well
loggings.
 Water-based mud can easily block the layers of very low permeability and
influence the capability.

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Properties:
The use of drilling fluids is an essential part of a rotary drilling process. Different
types of chemicals and polymers are used in designing a drilling fluid to meet
functional requirements such as appropriate mud rheology, density, mud activity,
fluid loss control property, etc... Today the choice of drilling fluids and their
additives has become complex (Caennet al. 2011), considering both the technical
and environmental factors (Amanullah 1993).
The preservation of the environment on a global level is now important as various
organizations have set up initiatives to drive the usage of toxic chemicals as DF
additives. Environmental pollution has been considered a serious threat while
drilling complex wells or high-temperature deep wells, which are now managed
by using advanced high-performance water-based DF systems.
As environmental protection has become a consideration before any oil and gas
resources exploration, people have to pay more and more attention to the DF for
environmental safety. Advances in recent technologies led to the development of
novel environmentally friendly Drilling fluids systems (Kok and Alikaya 2003;
Zhao et al. 2009; Lan et al. 2010). However, problems such as complicated
treating chemical synthesis technology, the lack of raw material for treatment
agents, and high initial cost have limited the development of the DF (Li et al.
2014).
The application of DF for environmental protection is limited in oil resources
exploration as the treating chemicals from natural macro molecular materials are
often of poor quality. However, later this delay brought the realization of negative
environmental impact from DF additives such as chemicals, polymers, salt water,
and oil-based fluids. Minimization of the environmental impact as well as safety
considerations of a drilling operation directly affects the choice of DF additive
systems.

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Due to the environmental regulatory agencies, products that have been used in
the past may no longer be acceptable.
As more environmental laws are enacted and new safety rules are applied, the
choices of additives and fluid systems must also be re-evaluated.
To meet the challenges of a changing environment, product knowledge and
product testing become essential tools for selecting suitable additives and DF
systems. There are many factors that are to be weighed when choosing a DF.
However, the key considerations are well design, anticipated formation pressures
and rock mechanics, formation chemistry, the degree of damage the DF imparts
to the formation, temperature, environmental effects and regulations, logistics,
and economics. To meet these key design factors, DFs offer a complex array of
interrelated properties. Five basic properties are usually defined by the well
program and monitored during drilling. These properties are listed as viscosity,
density, filter cake or filtration of water loss, solids content, and quality of water
make up.
Problems:
 Pipe Sticking
 Differential-Pressure Pipe Sticking
 Mechanical Pipe Sticking
 Loss of Circulation
 Hole Deviation
 Drill pipe Failures
 Borehole Instability
 Borehole-Instability Prevention
 Producing Formation Damage

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CAPTER II
Preparation of cellulose:
Cellulose is a polydisperse linear homopolymers consisting of regio-and enantio
selectively β-1,4glycosidic linked D-glucopyranose units (so-called) an hydro
glucose unit (AGU). As a consequence, the hydroxyl groups are positioned in the
ring plane while the hydrogen atoms are in the vertical position (axial). The
polymer contains free hydroxyl groups at the C-2,C-3, and C-6 atoms. Based on
the 0H groups and the oxygen atoms of both the pyranose ring and the glycosidic
bond, ordered hydrogen bond systems form various types of supramolecular
semi-crystalline structures. Cellulose is a versatile starting material for chemical
conversions, aiming at the production of artificial, cellulose derivative used in
many areas of industry and domestic life . The major purpose of this study is to
investigate the performance of local materials (cellulose from Ridge gourd
loofah) as a substitute for the preparation of drilling mud. As demand for oil and
gas increases, so does the need for extremely economic techniques to recover
these resources. The process of drilling must however be safe, cost effective and
environmental friendly. The main source of cellulose is that of polysaccharides in
different types of plants, often combined with other. The primary occurrence of
cellulose is lignocellulose materials found in woods which is the most important
and common source. Other cellulosic materials include agricultural residue, water
plant, grasses and other plant substances. Besides cellulose, they contain
hemicelluloses, lignin and a comparably small amount of extracts. Commercial
cellulose production concentrates on harvested sources such as wood or on
naturally pure source such as cotton.

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Extraction of cellulose:
The method of extraction was based on experiences in obtaining Fibers from
various agricultural by products. The Rich gourd loofah was bought from shops
in Chennai. The seeds were removed and its loofah used for the extraction. It was
observed that the loofah could be sensitive to extractive conditions. Strong alkali
conditions and/or heating of the loofah above 80ºC could result in the
disintegration of the loofah to sizes not suitable for high value fibrous
applications. The loofah was dipped into 0.5N sodium hydroxide solution with a
solution to cob ratio of 10:1 at room temperature overnight. The solution was
then heated to 80ºC for about 30 minutes. The extracts were drained and Fibers
formed were thoroughly washed first in warm water and later in cold water,
neutralized in dilute acetic acid solution to remove any remaining alkali, oven
dried and then blended.
Results of cellulose :
X-ray Powder diffraction is a rapid analytical technical primarily used for phase
identification of crystalline and can provide information on until cell dimension.
The analyzed material is finely grounded, homogenized and average bulk
composition is determined. Max Von Latue , in 1912 discovered that crystalline
substance act as three dimensional diffraction gratings for x-rays wavelengths
similar to the spacing of planes in crystals lattice, These diffracted x-rays are then
detected ,processed and counted. By scanning the sample through a range of
2θangles, all possible diffraction directions of the lattice should be attained due
to the random orientation of the powdered material. Conversion of the diffraction
peaks to d- spacing’s allows identification of the mineral because each mineral
has a set of unique d-spacing’s. Typically, this is achieved by comparison of d-
spacing’s with standard reference patterns.

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All diffraction methods are based on generation of X-rays in an X-ray tube. These
X-rays are directed at the sample, and the diffracted rays are collected. A key
component of all diffraction is the angle between the incident and diffracted
Limitations:
Homogeneous and single phase material is best for identification of an
unknown
Must have access to a standard reference file of inorganic compounds (d-
spacings,hkls)
Requires tenths of a gram of material which must be ground into a powder
For mixed materials, detection limit is ~ 2% of sample
For unit cell determinations, indexing of patterns for non-isometric crystal
1systems is complicated
Peak overlay may occur and worsens for high angle 'reflections'

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The below results shows XRD Results of the Experimental Cellulose (Rich
GourdLoofah):
Figure.1: Profile of XRD Cellulose
20 40 60 80
0
50
100
150
20 40 60 80
0
50
100
150
200
Integrated
Intensity
(cps
deg)
2-theta(deg)
Meas. data:AS-3147-A/Data 1
Intensity
(cps)
SOURCE: Langan , P.Nishiyama
and Chanzy.H (2001)

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CHAPTER -III
PREPARATION OF MUD:
Mud preparation
12 grams of barite was dissolved in 250mls of water and properly mixed using electric
mixer for 5 minutes. The resultant solution was left over-night for proper yielding. The
production methods of the drilling mud and the determination of the rheological and
allied properties of the mud were carried out based on the API drilling mud production
standards. The mixing method used by Joelet al (2012) was adopted. The various
quantities of the raw materials were measured using the graduated cylinder and
electronic weighing balance. The raw materials were then poured, one after the other,
with an interval of 5 minutes into the steel cup of the single spindle mixer. The
application of the raw materials was carried out in a descending order. The mud samples
were formulated in the absence and presence of various concentrations of the Rich
gourd loofah. The shear rheology is measured via a stress controlled rheometer (Anton
Parr Modular Compact Rheometer (MCR 52)) fitted with double gap geometry
(concentric cylinder system). The double gap geometry and dimensions of the system
used are shown. Controlled shear stress tests are conducted by varying the shear rate
from 0 to 1000. Rheological studies are carried out for different conditions of
temperatures (30, 50, 70, and 90ºc) and pressures (0.1 MPa and10 MPa). Additionally,
rheology is measured after cooling the sample from 90ºc back to Room Temperature.
It takes around 90 min for the cooling process which gives a representation of the
conditions drilling fluids would experience as they move back to the surface through
the annulus carrying up the drilled cuttings. Once cooled back to room temperature, the
tests are repeated to establish the effect of the entire heating process on the rheology of
drilling fluid. If a smaller deviation is observed in the viscosity of NWBM before and

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after cooling (AC), that shows better stability and indicates non-degradation at higher
temperatures.
Polymer Mud Preparation Procedure:
The preparation was made with the same procedure for conventional mud but in this
case, polyanionic cellulose was replaced with Rich Gourd loofah.
Preparation of Experimental Samples
Sample A: (standard mud: 2.0g PAC )
Sample B: (mud with 2.0 % Rich gourd cellulose )
Sample C: (mud with 4.0 % Rich Gourd cellulose)
Sample D: (mud with 6.0% Rich Gourd cellulose)
Determination of Mud Density (Mud Weight)
Calibration:
1. Remove the lid from the cup, and completely fill the cup with water.
2. Replace the lid and wipe dry.
3. Replace the balance arm on the base with knife edge resting on the fulcrum.
4. The level vial should be centered when the rider is set on 8.33 if not, add to or
remove short from the well in the end of the bream.
Procedure:
1. Remove the lid from the mud cup and fill the cup to overflowing with the mud to be
tested. If air bubbles have been trapped in the mud, tap the cup briskly on the side until
air bubbles break out.

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2. Replace the lid on the cup and rotate it until it is firmly seated. Do not vent hole with
your finger.
3. Make certain that some mud squeeze out the vent hole in the lid. Wash and wipe
excess mud from the exterior of the mud balance covering the vent hole, then dry the
balance. Vent hole must be covered during step 4.
4. Place the balance in its base with the knife-edges on the fulcrum rest.
5. Move the rider until the beam is balanced. The spirit level bubble should be on the
center line.
6. Read the mud weight at the edge of the rider nearest the fulcrum (towards the knife-
edge).
7. Clean and replace the instrument.
Determination of Mud Viscosity Using Anton Parr Rheometer:
A Rheometer is a precision instrument that contains the material of interest in a
geometric configuration, controls the environment around it, and applies and measures
wide ranges of stress, strain, and strain rate. Unlike a viscometer, which can only
measure the viscosity of a fluid under a limited range of conditions, a Rheometer is
capable of measuring viscosity and elasticity of non-Newtonian materials under a wide
range of conditions. Some of the most important properties that can be measured using
a Rheometer include Viscos-elasticity, yield stress, Thixotropy, extensional viscosity,
creep compliance and stress relaxation behavior, as well as process relevant parameters
such as die swell, melt fracture.
Rheological Studies:
Table 3shows the mud properties for sample A, B and C. The mud pH, mud density and
the specific gravity are shown for the three samples.

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TABLE 1 MUD PROPERTIES OF SAMPLE A, B AND C RESULTS:
Sample Name
( Rich gourd)
Sample pH Mud density
(ppg)
Specific Gravity
A 7 7 0.83
B 7.5 9.7 1.16
C 7.5 9.7 1.16
The pH, mud density and specific gravity of the mud prepared from Rich gourd Loofah
cellulose is higher than that of the standard mud.
RHEOMETER:
The mud samples were formulated in the absence and presence of various
concentrations of the Rich gourd loofah. The shear rheology is measured via a stress
controlled Rheometer (Anton Parr Modular Compact Rheometer (MCR 52)) fitted with
double gap geometry (concentric cylinder system). The double gap geometry and
dimensions of the system used are shown. Controlled shear stress tests are conducted
by varying the shear rate from 0 to 1000. Rheological studies are carried out for
different conditions of temperatures (30, 50, 70, and 90ºc) and pressures (0.1 MPa and
10 MPa). Additionally, rheology is measured after cooling the sample from 90ºc back
to Room Temperature. It takes around 90 min for the cooling process which gives a
representation of the conditions drilling fluids would experience as they move back to
the surface through the annulus carrying up the drilled cuttings. Once cooled back to
room temperature, the tests are repeated to establish the effect of the entire heating
process on the rheology of drilling fluid. If a smaller deviation is observed in the
viscosity of NWBM before and after cooling (AC), that shows better stability.

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Comparative studies of various concentration of with and without PAC:
Figure.2: Rich gourd loofah 2%
2 % concentration

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Figure.3: Rich gourd loofah 4%
4 % concentration

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Figure.4: Rich gourd loofah 6%
6 % concentration

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Figure.5: without Polyanionic cellulose
Without PAC

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CHAPTER IV
Conclusion:
Drilling mud (fluid) has been prepared using cellulose from processed rich gourd
loofah that was sourced locally. The result shows the following:
The pH value of the prepared mud is comparable to that of the standard mud.
Mud density of the prepared mud is higher than that of standard mud. Specific
gravity of the prepared mud was higher than that of the standard mud. The
rheological properties of the prepared mud were lower than that of the standard
mud. Cellulose from processed rich gourd loofah can control fluid loss in a
drilling mud effective and also at higher concentrations. The accessibility and low
cost of the rich gourd loofah which is a waste material can account for a reduced
well cost and increase in the concentration of the rich gourd loofah will give a
good fluid loss. The drilling fluids prepared from are environmentally friendly.
The cost effectiveness of this mud will reduce importation of mud or its additives
which will boost the economy. Rich gourd loofah improves the rheological
properties of water-based mud and mud sample with 4%,6% are potential
optimum concentrations of the rich gourd loofah additive. The locally sourced
rich gourd loofah is a suitable additive for the production of water based mud.

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CHAPTER V
Recommendation:
Drilling-fluid selection remains one of the most important components of a
successful well-construction operation. Drilling-fluid service companies help
operators to overcome the familiar issues (e.g., lost circulation) as well as the
challenges that are brought on by drilling in ultra deep waters, extreme HP/HT
formations, or remote environmentally sensitive areas by providing:
 Analytical tools
 Test equipment
 Stock point facilities
 Innovative materials
The ability to simulate downhole conditions and optimize fluid design will
continue to help reduce nonproductive time, and real-time management of hole
conditions through data feed from downhole tools allows the operator.
The demand for drilling-waste-management services that are dedicated to
reducing, recovering, and recycling the volume of spent fluids and drilled cuttings
continues to grow rapidly. These services and the related equipment have
demonstrated their worth by helping operators achieve environmental compliance,
reducing disposal costs, and returning more fluid and water for reuse in multiple
applications.
Drilling-fluid services of some kind are required on every well. They encompass
a broad spectrum of systems, products, software, personnel specializations, and
logistical support. As wells become more complex, total drilling costs can
increase dramatically. Because the drilling-fluid system comes in contact with
almost every aspect of the drilling operation, proper drilling-fluid selection can
help the operator minimize costs throughout the well-construction

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Reference:
[1]A. Mohammed, “Environmentally friendly mud additives for superior drilling-fluid design
to meet the current and future technical and environmental challenges”, The Oil and Gas
Review, Issue 11, 2007.
[2] A.O. Olatunde, M.A. Usman, O.A. Oladafenan T.A. Adeosan, O.E. Ufot, “Improvement
of rheological properties of drilling fluid using locally based material”, l. Petroleum and Coal,
vol.54, no.1, pp 65-75, 2011.
[3] K. Dieter, S. Hans-Peter and H. Thomas, “Cellulose”, Biopolymers online, Wiley, pp 1-6,
2005.
[4] I. L. Egun and M.A. Achandu, “Comparative Performance of Cassava Starch to PAC as
Fluid Loss Control Agent in Water Base Drilling Mud”, Discovery, vol.3, no.9, pp 1-4, 2013.
[5] T. Ademiluyi, O.F. Joel and A.K. Amandu, “Investigation of Local Polymer (cassava
starches) as a substitute for Imported sample in viscosity and fluid loss control of water
Based Drilling Mud”, ARPN Journal of Engineering and Applied Science, vol.6, no.12, pp 1-
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[6]Nmegbu, C. Godwin Jacob et al Int. Journal of Engineering Research and Applications,
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[7]Dagde, Kenneth Kekpugile and Nmegbu, Chukwuma Godwin Jacob ,DRILLING FLUID
FORMULATION USING CELLULOSE GENERATED FROM GROUNDNUT HUSK
International Journal of Advancements in Research & Technology, Volume 3, Issue 6, June-
2014.
[8]The use of grass as an environmentally friendly additive in water-based drilling fluids
M. Enamul Hossain, Mohammed Wajheeuddin.Pet. Sci. (2016) 13:292–303.
[9]N A Ghazali, A Sauki, N F Abu Bakar and S Mohamed .Oil Palm Empty Fruit Bunch
(OPEFB) Fiber as Lost Circulation Material (LCM) in Water Based Mud (WBM),IOP Conf.
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