The document discusses synthetic muds used in drilling fluids, detailing their compositions, types, and properties. It categorizes synthetic muds into four types: synthetic hydrocarbons, ethers, acetals, and esters, and outlines their components and functions. Additionally, it highlights the advantages and disadvantages of synthetic muds, emphasizing their low toxicity and environmental benefits compared to traditional drilling fluids.

2. Group Members
Mumtaz Ali 2014-pet-45
Jugnoo Iqbal 2014-pet-20
Muhammad Awais 2014-pet-15
Usman Amin 2014-pet-18
Abubakar 2014-pet-47
Junaid Hussain 2014-pet-31

3. Table of Contents
• Synthetic Muds
• Synthetic Mud Compositions
• Types of Synthetic Mud
• Properties of Synthetic Mud
• Functions of Synthetic Mud
• Aphron Drilling Fluids
• Structure of Aphron
• Composition
• Working

4. Drilling Fluids
All the fluids used in a well-
bore during drilling operation
are called “Drilling Fluids

5. Classification of Drilling Fluids
A drilling fluid can be classified by the nature of its
continuous fluid phase
There are four types of drilling fluids:
1. Water Based Muds
2. Oil Based Muds
3. Synthetic Muds
4. Gas Based Muds

6. Synthetic Muds
• A material produced by the reaction of a specific
purified chemical feedstock, as opposed to the
traditional base fluids such as diesel and mineral oil
which are derived from crude oil solely through
physical separation processe.
or
• A drilling fluid where the base fluid consists of non
water soluble organic compounds and where
neither the base fluid nor the additives are of
petroleum origin

7. Synthetic Mud Compositions
There composition is similar to the oil based mud:
• the continuous phase is a water insoluble synthetic organic material.
• Lignite
• Lime
• Emulsifier
• Wetting agents
• Rheology modifiers

8. • Organophilic clay
• Barite
• Thinners
• Gelling agents

9.  Emulsifiers, which often are metal soaps of fatty
acids, are added to the SBF to aid in forming and
maintaining the inverted emulsion.
 Wetting agents are added to ensure the solids in
the mud are SBF-wet, include polyamines, fatty
acids, and oxidized tall oils.
 Lime is added to make calcium soaps that aid in
emulsification of water in the SBF.
 Rheology modifiers and organophilic clays are
added to aid in suspending drill cuttings in the
mud.
 Barite (barium sulfate) is used to increase the
weight of the drilling mud, counteracting
formation pressure and thus preventing a blowout.

10. Additives Concentration in Drilling Mud
Pounds/Barrel
Rheological Modifier 9.0 - 14.0
Fluid Loss Additive <1.0 - 2.0
Lime 1.0 - 8.0
Organophilic Clay 6.0 - 9.0
Wetting Agent 5 – 8
Emulsifier 0 - 1.0
Table : Typical concentration ranges of the major
additives in SBFs. Modified from McKee et al. (1995).

11. Types of Synthetic Mud
Synthetic base fluids may be classified into four general categories:
1. Synthetic hydrocarbons
2. Ethers
3. Esters
4. Acetals

12. 1. Synthetic Hydrocarbons
Polymerized olefins are the most frequently used
synthetic hydrocarbons in SBFs today.They include:
 Linear alpha olefins (LAOs)
 Poly alpha olefins (PAOs)
 Internal olefins (Ios)

13. Linear Alpha Olefins
• LAOs are produced by the polymerization of ethylene.
• Ethylene (C2H4), the smallest unsaturated hydrocarbon, is oligomerized by
heating in the presence of a catalyst and triethyl aluminum to produce LAOs
with different hydrocarbon chain lengths.
• LAOs have molecular weights ranging from 112 (C8H16) to 260 (C20H40).
• The LAO mixture is distilled to produce different molecular weight blends.
• The physical-chemical properties of the mixtures can be altered systematically
by changing the chain lengths and branching of the LAO molecules.
• Typical LAO mixtures used in SBFs are LAO C14C16 (a blend of C14H28 and C16H32 LAOs)
and LAO C16C18.

14. Poly Alpha Olefins
PAOs are manufactured in a four- to five-step process:
1) polymerization of ethylene to form a series of linear alpha olefins;
2) distillation to isolate LAOs of the desired chain length;
3) oligomerization of the LAOs to produce PAOs;
4) hydrogenation to saturate the PAOs;
5) distillation to isolate PAOs with the desired physical-chemical properties
PAOs may be hydrogenated, producing alkanes for some applications
• LAOs used to manufacture PAOs include 1-octene (C8H16) and 1-decene (C10H20

15. • unsaturated PAOs are preferred to the saturated in
applications where PAO cuttings may be
discharged to the ocean.
• The average PAO is C20H42 (Eicosane) with a
molecular weight of 282.6 and an aqueous
solubility less than 1 µg/L.

16. Internal Olefins
• IOs are formed by isomerization of LAOs in the
presence of heat and a suitable catalyst.
• Isomerization of a LAO decreases its pour point
and flash point.
• Commercial IOs usually have a chain length of 16
(C16H32) or 18 (C18H36) carbons.
• The IO mixture may be hydrogenated to produce
saturated hydrocarbons.

17. • In today’s market, LAOs and IOs usually are
preferred over PAOs. LAOs and IOs often are used
in blends that are designed to achieve a balance
among the physical properties important to the
drilling operation (e.g. viscosity, pour point, flash
point, etc.).

18. 2. Ethers
• Alcohols with different chain lengths are
condensed and partially oxidized to produce
mono- and di-ethers.
• Ethers are saturated hydrocarbons with an oxygen
atom in the center.
• Hydrocarbon chain lengths and branching are
selected to optimize drilling properties and
minimize toxicity.
• Ethers are more stable both chemically and
biologically than esters or acetals.
• Ether SBFs have a high hydrolytic stability.

19. 3. Acetals
• Acetals are dialkylethers that are closely related to ethers.
• They are formed by the acid-catalyzed reaction of an aldehyde with an alcohol or
carbonyl compound (One mole of aldehyde and two moles of alcohol).
• Acetals are relatively stable under neutral and basic conditions, but may revert back
to the aldehyde and alcohol under acidic conditions.
• A typical acetal in a SBF has the formula, C20H42O2, and has a molecular weight of 314.3

20. 4.Esters
• Esters are formed by the reaction of a carboxylic
acid with an alcohol under acidic conditions.
• The ingredients of esters used in SBFs include
fatty acids (carboxylic acids) and alcohols with
different chain lengths.
• 2-Ethylhexanol is the alcohol used most frequently;
however, glycerols may also be used.
• The fatty acids usually are derived from natural
vegetable or fish oils.

21. • Esters are somewhat polar and more water- soluble.
• An example of ester used in SBFs is a mixture of C8 through C14 fatty acid
esters of 2-ethylhexanol.e.g C26H52O2
• Esters also may be mixed with synthetic hydrocarbons (LAO, IO, or PAO) in
an SBF to attain some particular drilling performance characteristic.
• Esters are relatively stable under neutral conditions, but may undergo hydrolysis
and revert back to the acid and alcohol under basic or acidic conditions.

22. Properties of Synthetic Mud
 Mud Weight or Mud density(MW)
 Plastic viscosity(PV)
 Yield point(Yp)
 Gel Strength
 Filtration
 Sand content

23.  pH
 Colorless
 Odorless
 Non-toxic

24. Functions of Synthetic Mud
1) Containment of pore pressure
2) Hole cleaning/ Transport cuttings
3) Suspend cuttings
4) Clean the bit and other in-hole tools
5) Lubricate the drill string & drilled hole
6) Assist in gathering of subsurface geological
data and formation evaluation

25. 7) Prevent adverse effects of H2S and CO2
8) Assist in cementation
9) Deposit filter cake
10) Stabilize weak or incompetent zones
11) Reduce filtrate invasion
12) Protect formation productivity
13) Powering down-hole tools
14) Support weight of tubular

26. Advantages:-
• High ROP
• Long bit life
• Excellent shale inhibition
• Thermally stable
• Low reservoir damage
• High lubricity
• Low torque
• Low Corrosion
• Low fluid loss
• Reduced chance of pipe sticking
• High solid tolerance

27. • Salt not dissolve
• Natural gas is less soluble in SBFs than in most OBFs, making it easier to detect gas kick
• SBFs released much smaller amounts of vapors than diesel or mineral oil based drilling fluids
these vapor losses are of importance mainly because of their toxicity through inhalation
to personnel working near the mud storage and treatment systems on the platform.
• Particularly useful for deepwater and deviated hole drilling.
• SBFs are designed to be less toxic and degrade faster than OBFs.
• Synthetics have certain technical and human health advantages over most mineral oils and
diesel fuel
• They are less volatile than OBFs and their vapors are free of aromatic compounds
• Thus, the use of SBFs can reduce vapor inhalation by workers in closed, poorly
ventilated areas on the drilling platform.

28. Disadvantages:-
• High cost
• Electric log difficulties
• Expensive lost circulation
• Poor cement bond possible
• Messy working environment
• Difficulty detection crude oil
• Fire hazardous
• Logistics
• Pollution

29. Aphron Drilling Fluids
• Used to minimize fluid invasion into low-pressure
permeable or fractured formation by
I. Forming soft internal seal
II. Creating microenvironment

30. Structure of Aphron
 The aphron is composed of a core of air (gas) that
is stabilized by a polymer/surfactant shell
 The air core of an aphron is enveloped by a much
more stable surfactant tri-layer
• an inner surfactant film enveloped by a viscous
water shell
• an outer bi-layer of surfactants

31. Structure of Aphron

32. Stability of Aphron
• Stability of aphron depends on thickness and
viscosity of the encapsulating shell
• Aphrons in circulation change their volume with
pressure change according to Boyle’s law
• Shell must have a minimum viscosity to prevent
phenomenon known as the “Marangoni effect”

33. Composition (water-based aphron)
• Fresh water/brine
• Soda ash
• Biopolymer blend
• Polymer blend
• pH buffer
• Surfactant
• Biocide

34. • The base fluid is highly shear-thinning and exhibits
an extraordinarily high LSRV (Low-Shear-Rate
Viscosity) with low thixotropy (flat gels).

35. Composition (oil-based aphron)
• oil or synthetic fluid
• clay or Polymer Blend
• Surfactant
• Water
• Emulsifiers

36. Working
• When the drilling fluid enters a formation, the
aphrons expand to a small extent and, more
importantly, move forward rapidly by means of
“bubbly flow” to concentrate at the fluid front and
create a “microenvironment” that separates the
borehole from the formation pressures.

37. Mud Cake Formation