Fichier PDF

Partage, hébergement, conversion et archivage facile de documents au format PDF

Partager un fichier Mes fichiers Convertir un fichier Boite à outils PDF Recherche PDF Aide Contact



cours M.akid .pdf



Nom original: cours M.akid.pdf
Titre: Microsoft PowerPoint - WS MUDS013 - Advanced Drilling Fluids SLB WISE.ppt
Auteur: Thierry Maysounabe

Ce document au format PDF 1.3 a été généré par PrimoPDF http://www.primopdf.com / PrimoPDF, et a été envoyé sur fichier-pdf.fr le 03/11/2016 à 21:19, depuis l'adresse IP 197.27.x.x. La présente page de téléchargement du fichier a été vue 524 fois.
Taille du document: 42.9 Mo (388 pages).
Confidentialité: fichier public




Télécharger le fichier (PDF)









Aperçu du document


Advanced Drilling Fluids for SLB WISE

WellStaff Middle East©

Course Content


Introduction about Drilling Fluids



Clay Chemistry



Mud Description:




Drilling Fluids Testing
Water-Based Muds
Oil-Based Muds



About Mud Report



Mud Contaminants



Solid Control



Waste Management



Formation Damage & Productivity



Mud discussions:









HSE Aspects
Basic Hydraulics Calculations
Hole Cleaning
Stuck Pipe
Reactive Shales Problems
Lubrication Processes
Equipment Failure vs Drilling Fluids (wear, corrosion)
Extended Reach Wells

WellStaff Middle East©

1

Спасиба Дмитри …

WellStaff Middle East©

About Drilling Fluids

WellStaff Middle East©

2

Drilling Fluids: Definition

A mixture of chemical additives in a
liquid phase
Liquid phase may be fresh water, salty
water, diesel or synthetic oil

WellStaff Middle East©

History

1900

water & clays

1940

weighted WBM

’50-60

Cellulosic polymers

’70

PHPA systems

’80

Mineral oils (damage)

’90

Synthetic oils (environment)

WellStaff Middle East©

3

Functions of Drilling Fluid
Overcome formation fluid pressure
Cool and lubricate the bit
Clean the bottom of the hole
Carry cuttings to the surface
Permit cuttings removal
Geology Information
Allow interpretable electric logs to be obtained
Deposit an impermeable wall cake
Avoid damage to productive zones
Protect the drill pipe against corrosion
WellStaff Middle East©

WellStaff Middle East©

4

Choosing a mud system
The selection regarding the type of mud is based on:



Drilling problems



Possibility of converting the mud in use to another type of mud



Cost



Products availability



Environmental factors



Case histories

ECONOMICAL

TECHNICAL
TARGET

WellStaff Middle East©

ENVIRONMENTAL

Choosing a mud system

Mud Properties VS Functions



The characteristics of a mud can influence its functions e.g. the formation
pressure is checked by the hydrostatic pressure. The hydrostatic pressure is
modified by the density or specific weight.



As the uncontrolled density increases, the pressure drop increases. The
consequence is a possible loss of circulation.

WellStaff Middle East©

5

Choosing a mud system
Mud characteristics modifications

Fluids engineering always need an exchange of conditions to treat and keep
optimum drilling. For instance, an out of proportion viscosity increasing,
improves the hole cleaning:
The loss of pressure increases
The capacity of removing solids in the mud decreases
The penetrating rate slows down
The dilution treating increases a/o the preparation, with consequent

costs increasing

WellStaff Middle East©

CLAYS
and
SHALES

WellStaff Middle East©

6

CLAYS & CLAY MINERALS

Why is clay mineralogy important ?
Addition of commercially mined clays

(Viscosity,Thixotropy, and Wall Cake Building Properties)

One or more clay minerals are present in nearly
all sedimentary rocks : their reaction to the
drilling process can produce major problems
(Hole Enlargement, Sloughing, Shale Hydration, Rheological
Problems)

WellStaff Middle East©

CLAYS & CLAY MINERALS

Magnitude of Potential Problems :
Large : Shales, siltstones, mud stones …
comprise > 50% of sedimentary rocks
Sandstones : may contain as much as 2030% clay minerals

WellStaff Middle East©

7

CLAYS & CLAY MINERALS

CLAYS DEFINED BY :
Physical Properties
Chemical & Mineral Properties
Size
Structure
Reactivity in water - Swelling/Non-Swelling

WellStaff Middle East©

CLAYS & CLAY MINERALS

CLAY COMPOSITION
ELEMENTS :
Oxygen
Silicone
Aluminum
Calcium
Magnesium
Potassium

NON-CLAY MINERALS :
Quartz
Feldspar
Pyrite
Calcite

WellStaff Middle East©

8

CLAYS & CLAY MINERALS

Structure :
Hydrous aluminum silicates of a layer-type lattice
structure with magnesium, iron, and potassium
located between the layers or substituted within the
lattice.
Components :
Silica tetrahedron and alumina octahedron arranged
in a sheet like structure.

WellStaff Middle East©

CLAYS & CLAY MINERALS


One of the distinguishing characteristics of clays is that when it is
added to water it disintegrates into particles that are shaped like very
thin, flat platelets.



The area of each surface is many order of magnitudes greater than the
edges



In the dry sate, in a sack, the platelets are stacked surface to surface.



This is referred to as the aggregated state.

WellStaff Middle East©

9

CLAYS & CLAY MINERALS

Layered Clays :
Smectites
Illites
Kaolinites
Chlorites
Vermiculites
Mixed-layer Clays

Chain-type Clays :
Attapulgite
Sepiolite
One Unit Layer

Clay layer sheet like structure

Clay layer chain or needle like structure

WellStaff Middle East©

Typical Structure of clay

Cation exchangeable

OH

Hydroxyl
Oxygen
Aluminium /Magnesium
Silicium

WellStaff Middle East©

10

LAYERED CLAYS

WellStaff Middle East©

SMECTITE

WellStaff Middle East©

11

SMECTITE
The least stable
Most susceptible to hydration
Most susceptible to diagenetic alteration
Montmorillonite and Bentonite
WellStaff Middle East©

Montmorillonite Structure
Basic Crystal : 3 layers (2 silica, 1 alumina)
-----Silica
Tetrahedron
Alumina
Octahedron

Silica
Tetrahedron

---------

Basal Plane
(Na,Ca,Mg,etc.,&H2O)

Unit Layer

-----WellStaff Middle East©

12

ILLITE

WellStaff Middle East©

ILLITE
Structurally similiar to smectite (3 layers)
Aluminum substituted for silica in tetrahedron
Greater charge deficiency
Deficiency frequently satisfied by potassium ion
Essentially inert to hydration
no interlayer water
exception: swelling if divalent cations
WellStaff Middle East©

13

Structure Illite

K+
SiO4

Al3+

Si

Gibbsite
Al

Al(OH-)5O

SiO4

Al3+

Si
K+

WellStaff Middle East©

KAOLINITE

WellStaff Middle East©

14

KAOLINITE
2 layers: 1 silica sheet and 1 alumina sheet
d=2.76 Å
Neutrally charged surface
Very little expansion or hydration : strong
hydrogen bonds

WellStaff Middle East©

CHLORITE

WellStaff Middle East©

15

CHLORITE
Similiar to smectite (3 layers) except for a layer
of magnesium hydroxide between the clay
sheets
Neutrally charged surface
Non swelling : strong bondings

WellStaff Middle East©

Mixed Layered Clays

WellStaff Middle East©

16

Mixed-Layers Clays
Formed by the alteration of different clay
minerals
Typically illite/smectite combination
Proportion of swelling to nonswelling layers
determines expandability

WellStaff Middle East©

Chain Type Clays

WellStaff Middle East©

17

Chain-Type Clays
Elongated particles inducing low filtration control:
brush pile effect results in many void spaces through
which water can pass.

No hydration but require shear thus effective in high
salt content systems
WellStaff Middle East©

Synthesis

WellStaff Middle East©

18

WellStaff Middle East©

WellStaff Middle East©

19

WellStaff Middle East©

Properties

WellStaff Middle East©

20

CLAYS & CLAY MINERALS

Base Exchange:
Occurs when certain cations in solution are exchanged
for others which are adsorbed on the crystalline surfaces
of the clay
Adsorbed cations control the tendency of the clay to
swell or disperse in the presence of water
Sodium, Potassium, Magnesium and Calcium
Cations are adsorbed on the surfaces, between
platelets, and around edges of the structural units
WellStaff Middle East©

CLAYS & CLAY MINERALS

Factors Affecting Base Exchange in Clays :
Relative replacement power of available cations
Type of clay
Amount of charge deficiency on the clay surface
Concentration of cations in solution
Size and type of replacing cation

WellStaff Middle East©

21

CLAYS & CLAY MINERALS

Replacement Power, 2 Factors :
Number of charges on the cation :
Cations with more positive charges will have greater
replacement power

Size of the hydrated cation :
The smaller the cation, the easier it is to exchange, and
the less hydration will occur
WellStaff Middle East©

Cations Sizes

Ionic diameters
Ion

Ionic Diameter (Angstroms)
Not hydrated

Hydrated

Na+

1.96

11.2

K+

2.66

7.6

+

2.86

7.6

Mg2+

1.56

21.6

Ca2+

2.12

19.2

Ba2+

2.86

17.6

Al3+

1.14

*

NH4

*Not available

WellStaff Middle East©

22

CLAYS & CLAY MINERALS
Order of Cation Replacibility :
EASIEST
Lithium
Sodium
Potassium
Magnesium
Calcium
Hydrogen
HARDEST

WellStaff Middle East©

CLAYS & CLAY MINERALS

Clay and Clay Minerals Base Exchange Capacities
C lay M ineral
M ontm orillonite
Illite
K aolinite
A ttapulgite-S epiolite

M eq/100g of D ry C lay
50-130
10-40
3-15
10-35

WellStaff Middle East©

23

CLAYS & CLAY MINERALS

Relative Concentration :
When cations of a lower replacement power are
present in greater conc. than those of a higher
replacement power, the desired base exchange
may not occur

WellStaff Middle East©

CLAYS & CLAY MINERALS

Cation Size :
Determined by the size of the atomic
radius of the cation and the amount of
water required to hydrate the cations.
The smaller the cation, the easier it is to
exchange and the less hydration will
occur.
WellStaff Middle East©

24

CLAYS & CLAY MINERALS

States of Clay :
Remember Aggregation
Clay platelets are stacked paralell to each other
This state exists when clay is not hydrated

Dispersion :
Occurs when the clay platelets separate

Aggregated or dispersed clays can undergo
flocculation or deflocculation
WellStaff Middle East©

CLAYS & CLAY MINERALS

Swelling takes place when water infiltrates between the platelets,

forcing them apart.

This is called the dispersed state.
The amount and rapidity of dispersion is determined by the cations

on the clays, the pH of the solution, the salinity of the water, the
temperature, the amount of mixing shear, and other factors.

WellStaff Middle East©

25

CLAYS & CLAY MINERALS



Once a clay is hydrated its natural tendency is for the individual
particles to rejoin.


Instead of coming back together face-to-face as in the aggregated state,
the particles tend to attach themselves edge-to-face.

EDGE to FACE




EDGE to EDGE

This type of clay (electrically induced) alignment is called flocculation.
The edges of the clays are thought to be positively charged as opposed to
the negatively charged clay basal plane area

WellStaff Middle East©

CLAYS & CLAY MINERALS

Flocculation Mechanisms to create the property
unique to clay slurries called “gel structure”:
Time
Electrolyte Concentration
Temperature
Solids Crowding
WellStaff Middle East©

26

CLAYS & CLAY MINERALS
Gels can be broken in a mud by mixing or flowing the fluid.
The gel strengths of a mud relate directly to its ability to suspend
particles during low flow or when the pumps are stopped.
Since flocculation leads eventually to the undesirable mud
properties of high viscosities, gel strengths, and filtrates, the
mud engineer takes steps to deflocculate the mud.
By adding the proper additives the flocculated clay is partially
deflocculated.
The deflocculated state is similar to the dispersed state.
Deflocculation usually results in reduced viscosities and better
control of the API filtrate.
WellStaff Middle East©

CLAYS & CLAY MINERALS

CLAY PARTICLE ASSOCIATION
FLOCCULATION

DEFLOCCULATION
(EDGE TO FACE)

(EDGE TO EDGE

DiSPERSION

AGGREGATION
(FACE TO FACE)

WellStaff Middle East©

27

Balanced Activity Concept

Shale formations have a natural potential to adsorb
water.
This sets up a "suction potential" also called demand
for water.
Surfactants around water droplets act as a semipermeable membrane (as an osmotic membrane)
and water can transfer between the emulsified water
and the water in the pores of the shale.
Solution is to balance the demand for water, i.e. the
activity between the shale and the emulsified water
no exchange will take place
WellStaff Middle East©

Balanced Activity Concept (Cont.’d)

The brine phase activity is thus
primordial:
Addition of salt to water combines the

water molecules to reduce the vapor
pressure (the activity !).
Activity is inversely proportional to
chloride content.
Divalent ions (Ca2+, Mg2+) suppress
activity further than saturated sodium
ions.
Calcium soaps being major part of
emulsifying system, CaCl2 brines are
preferred.
WellStaff Middle East©

28

MBT

Measure of the capacity of anionic clays to
adsorb cationic methylen blue dye = active
clay
CEC = VMBdye / Vmud
Eq.bentonite = 14.25 x CEC

WellStaff Middle East©

CEC
- {Cation Exchange Capacity}
CEC - {Cation Exchange Capacity}

WellStaff Middle East©

29

MBT Results

WellStaff Middle East©

WellStaff Middle East©

30

Testing Drilling Fluids

WellStaff Middle East©

Mud Testing

API drilling fluids tests
Drilling fluids are continually measured and adjusted at the
wellsite:
Basic physical and chemical tests serve to monitor the drilling
fluid conditions.
American Petroleum Institute issues recommended practices
for testing procedures and equipments,
API RP 13B -1 water based
API RP 13B -2 oil based drilling fluids

WellStaff Middle East©

31

Mud testing

Standard API tests:
Tests common to water and oil based muds:
Mud weight,
Filtration,
Water, Oil and Solids,
Viscosity and Gel strength,
Marsh Funnel Viscometer.

WellStaff Middle East©

Mud testing

Standard API tests / Water - based (RP 13B-1)
Sand
pH
Methylene blue capacity
Drill pipe corrosion
Chemicals analysis
Alkalinity
Chloride
Total hardness
Sulfide
WellStaff Middle East©

32

Mud testing

Standard API tests / Oil - based (RP 13B-2)
Electric stability
Activity
Oil and water content from cuttings
Chemicals analysis
Whole mud alkalinity
Whole mud chlorides
Whole mud calcium

WellStaff Middle East©

WellStaff Middle East©

33

Mud Properties

WellStaff Middle East©

Mud Properties





Mud Weight
Rheological Properties
Solid Analysis
Filtration






Alkalinity
Chlorides
Total Hardness
Clays & Shales

WellStaff Middle East©

34

Mud Weight

WellStaff Middle East©

Mud Weight (density)
Hydrostatic Pressure
PH =

H ×d
10.2

(bar)

Mud Weight: ppg or
g/cm3
Atmospheric or
Pressurized Balance
WellStaff Middle East©

35

Mud Weight (density)

The density of a fluid will needs adjustments, upon Reservoir
Pressure:
Weighting up with solids, salts or heavy fluids
Weighting down will be done by dilution with fresh water or a
lower- density fluids,
Testing with mud balances or hygrometer

WellStaff Middle East©

Mud weight: mud balance
A beam balance consisting
of a cup and a graduate arm
carrying a sliding weight and
resting on a fulcrum
Used to determine the
density (or weight) of drilling
mud
Sources of Error:






Improper Filling
Air/Gas Entrapment
Calibration
Dirty Balance
Cuttings

WellStaff Middle East©

36

Density

ECD:
Equivalent Circulation Density
Calculated at the bottom of hole or

anywhere else in the open hole

WellStaff Middle East©

Density - Procedure

Set the instrument on a flat, level surface

WellStaff Middle East©

37

Density - Procedure

Measure the temperature of the mud.

WellStaff Middle East©

Density - Procedure

Fill the clean, dry cup with mud to be tested.

WellStaff Middle East©

38

Density - Procedure

Put the cap on the filled mud cup...

WellStaff Middle East©

Density - Procedure

Rotate the cap until firmly seated. Ensure
some mud is expelled through the hole in the cap.

WellStaff Middle East©

39

Density - Procedure
Hold cap firmly on cup (with the cap hole covered and
wash or wipe the outside of the cup clean and dry.

WellStaff Middle East©

Density - Procedure

Place the beam on the base support …

WellStaff Middle East©

40

Density - Procedure

Balance it by moving the rider along the
graduated scale.

WellStaff Middle East©

Density - Procedure

Balance is achieved when the bubble is under
the center line.

WellStaff Middle East©

41

Density - Procedure

Read the mud weight at the edge of the rider
toward the mud cup. (To the left of the pointer)

e.g. mud weight = 12.3 lb/gal or 1.47 sp gr
WellStaff Middle East©

Density - Calibration
Calibrate frequently with fresh water. Fresh
water should give a reading of 8.345 pounds per
gallon or 1.0 specific gravity

WellStaff Middle East©

42

Density - Calibration
To correct an improperly calibrated balance: remove
screw from scale tip and remove or add lead shot to
calibrate balance.

Remove screw

Remove or

add lead shot

WellStaff Middle East©

Rheology

WellStaff Middle East©

43

Rheology - Definitions
Definitions:
Rheology is the science dealing with deformation and flow of
a Fluid.
Viscosity is the internal resistance of a fluid to flow
Rheology is tested with the Fann VG-meter
Commonly used VG viscometers are specially designed to
facilitate the use of the Bingham plastic Model in conjunction with
drilling fluids in the field
A torsion spring-loaded stator gives a dial reading proportional to
torque and analogous to the shear stress.
The speed of rotation (rpm) is analogous to the shear rate.
WellStaff Middle East©

Rheology
Viscosity-Shear relation
Internal resistance is the
frictional force between
layers of a fluid as they
slide past one another
Internal relation is known
as Shear Stress (lb/100ft2)
= Force causing the
shearing / surface of the
platelet
Relative speed of layers
is named Shear Rate (s-1)
WellStaff Middle East©

44

Rheology – Oilfield Calculations
Measure deviations at 600, 300, 200, 100, 6 and 3 rpm.
Field Approximation: viscosities are calculated from the
readings at 600 rpm and 300 rpm.
Calculations:
Apparent viscosity: AV = (Fann600) / 2

(cP)
(cP)

Plastic viscosity:

PV = Fann600 - Fann300

Yield point:

YP = Fann300 – PV

Gel strength

GS0 and GS10

Rheological index

n = 3.32 log(Fann600/Fann300)

Consistency index

K = Fann600 / 1020

(lb/100ft2)

WellStaff Middle East©

Fann Rheometer - Overview

WellStaff Middle East©

45

Marsh Funnel and Plastic
Measuring Beaker

WellStaff Middle East©

Marsh Funnel - Equipment

Funnel Viscosity
A timed rate of

flow from a
specially
designed funnel.
General
rheological
indicator for
Dummies
WellStaff Middle East©

46

Marsh Funnel - Procedure

Measure the temperature of the fluid.
WellStaff Middle East©

Marsh Funnel - Procedure

Cover Tip of Funnel.

Pour Mud Through Screen
To Top Line or bottom of
the screen

WellStaff Middle East©

47

Marsh Funnel - Procedure

Remove finger and start the stopwatch.

WellStaff Middle East©

Marsh Funnel - Procedure

Stop (1) timer and (2) fluid flow when fluid level reaches the
1 quart or 1 liter mark.
WellStaff Middle East©

48

Marsh Funnel - Procedure

Report the temperature and time to the nearest second as marsh
funnel viscosity (e.g. 46 seconds/quart at 85 deg F)
WellStaff Middle East©

Marsh Funnel - Procedure

The Marsh Funnel is calibrated to out-flow one quart (32 oz) of
fresh water at a temperature of 70 ± 5 °F in 26 ± 0.5 seconds.
WellStaff Middle East©

49


Documents similaires


cours m akid
tutorial8
for sale france brittany
dridri argiles
adosh water wells drilling profile 2013
tableau selection fluide de substitution rs 7


Sur le même sujet..