WELCOME TO

DRILLING FLUID

SEMINAR

PT. CPI, 8 AND 22

AUGUST 2001

AGENDA

REMARKS FROM DRILLING MANAGER

CLASS EXPECTATION

DRILLING SHE POLICY

MUD WASTE MINIMIZATION

CLAY CHEMISTRY AND INHIBITION

DRILLING FLUID

SOLID CONTROL EQUIPMENT

MUD REPORT

OTHERS

CERTIFICATION TEST

CLASS

EXPECTATION

PLEASE SPEAK UP

ATTENDEES EXPECTATION

ELIMINATE SHE INCIDENT AND

ACCIDENTS

STRENGTHENED COOPERATION

IMPROVE KNOWLEDGE

SHARE EXPERIENCE

ACHIEVE OPTIMUM DRILLING

FLUID COST AND WELL COST

DRILLING SHE

POLICY

PT. CPI

PPE

HARD HAT

SAFETY SHOES (ANTI SLIP, LONG)

SAFETY GLASSES

DUST FOE

EAR PLUG

HAND GLOVES

COVERALL

PPE

HARD HAT, SAFETY GLASSES AND

SAFETY SHOES ARE A MUST

WHENEVER WORK AT THE RIG.

OTHERS PPE DEPEND ON TYPE OF

JOB AND ITS PLACE.

“WITHOUT PROPER PPE IS NOT

ALLOWED TO WORK IN CPI”

MUD WASTE GUIDELINE

LEAD TO ACHIEVE OR EXCEED

COMPLIANCE

TO FORMULATE CPI

ENVIRONMENTALY SOUND

DISPOSAL OF MUD WASTE

TO COMPLY GOVERNMENT

REGULATION

DRILLING SHE

– PERSONAL PROTECTIVE EQUIPMENT

– MUD WASTE CONTROL AND

MANAGEMENT

– MUD WASTE REDUCTION PROGRAM

– MUD MIXING PROCEDURE

– MSDS

– MUD MATERIAL HANDLING

MUD WASTE CONTROL

SAMPLING (AS PER SOP)

– SURFACE SOIL

– FRESH MUD

– CUTTINGS AT TOP OF PAYZONE

– MUD AT TD

– CUTTINGS AT TD

TEST PROCEDURE LIMITS

FOR CUTTING TO BE

BACKFILLED AT LOCATION THM (TCLP) < LIMIT

TDS (TOTAL DISSOLVED SOLID) <

10,000 PPM

TEST LIMIT FOR EFLUENT

WASTE WATER TO WATER

BODY THM (TCLP) < LIMIT

TDS (TOTAL DISSOLVED SOLID) < 10,000 PPM

OC (OIL CONTENT) < 25.0 PPM

TSS (TOTAL SUSPENDED SOLID) < 10,000 PPM

PH 5-10

96 HRS LC50 > 30,000 (SPP)

ENVIRONMENTALY

FRIENDLY MUD

KLM; TDS < 10,000 PPM

LOW KCL %; < 2%

MUD WASTE RECORD

DAILY RECORD IN MUD REPORT

CUMULATIVE WASTE VOLUME

EVRY RIG RELEASE

IT MAY BE REPORTED UNDER ONE

MUD REPORT (DIMS)

WASTE

MINIMIZATION IN

DRILLING

OPERATIONS

PT CPI

Waste minimization benefits :

reduced operating and waste management costs;

increased revenue;

reduced regulatory compliance concerns;

reduced potential liability concerns;

and improved company image public relations.

Waste management hierarchy:

Source reduction

Recycling

Treatment

Disposal

The first two above are more preferred.

Source reduction

Preplanning

– Drill site construction

• Rainwater is diverted away from disposal pit

• Location size is built as required

• R&L is properly built

– Drilling Fluid System

• Suitable system

• Proper Solid Control Equipment

– Disposal Pit

• Enough capacity

• No leaking

• Properly built (V shape)

Source Reduction (cont’d) :

Product Substitution

– Drilling Fluids

• Non toxic/hazardous system

– Drilling Fluid Additives

• Non toxic/hazardous additives

– Pipe Dope

• Lead free and biodegradable pipe dope

• Recycle protectors

• Ex container is completely free

Source Reduction:

Product Substitution (cont’d);

– Organic Solvent (for cleaning rig equipment

and tools)

• Use non toxic /hazardous such as citrus-based

• Don’t use toxic solvent such as trichloroethane and

carbon tetrachloride.

– Paint and Thinners

• Use water based paints only to avoid usage of

toluene

Source reduction (cont’d):

Proper Solid Control Equipment

– Improvement 30 % of SCE can reduce 40-50 % waste

Material Balance and Mud system monitoring

Closed Loop Drilling System

Mud runoff from pulled drill string

– Dry pull

– Use mud bucket

Source reduction (cont’d) :

Reduction in Water Use

– Rig wash hoses

• Use water wisely

• Hoses is equipped with nozzle

• Collect rig wash for reuse

– Drilling Fluid System

• Good SCE to reduce dilution

• Build only optimum mud volume

– Dewatering Waste Drilling Fluid

– Avoid water to enter disposal pit

– When release don’t discharge water from water tank into disposal pit

Source Reduction (cont’d):

Good House Keeping and Preventive Maintenance

– Drip Pans and Other Types of Containment

• Drip pans beneath engines to avoid oil spill

– Preventive Maintenance

• Regular maintenance of equipment to avoid engine leaks

– Chemical and Material Handling

• Covered, labeled, protected to avoid broken and spill of materials

• Equipped with MSDS

• Inventory control to avoid missing, un protected, etc.

Recycling

Drilling Fluid

– Recycled for next well

Reserve Pit Water

– Use for mixing water

Paint Solvent reuse

Commercial chemical reuse

Treatment in CPI :

Further treatment will be done in CMTF or

other mud waste system

– Transfer mud waste only

– Record the loads

– Discharge to dedicated pit

– Do not mix oil contaminated mud waste with

non contaminated mud

Summary : How to Minimize

Waste ?

Reduce

Recycle

----------------

Treat

Dispose

---------------

Lets implement in CPI !!

MUD

MATERIALS

LOSSES

REDUCTION DRILLING

TEAM TARGET

2001

BACK GROUND

LOSSES 21.1 % (1997-1998 Data) = $

2.1 MM

– CONTROLLABLE LOSSES 18.6 % = $

1.86 MM

• Solidified materials = 6.9 %

• Broken packaging = 6.5 %

• Careless = 5.2 %

– Improper usage = 2.5 %

MUD MATERIAL VALUE/YEAR = $ 10 MM

LOSSES GAP ANALYSIS

Improvement

Minimum 5 nails in

every crossed out site

Total wood should be

5 Pcs in bottom, 6 Pcs

in top & 3 Pcs in

Middle.

Low quality of local

product.

– Weak wood pallet

A. Packaging

LOSSES GAP ANALYSIS

Improper stacking

system in jungle box

(parallel)

Low quality of bag

paper (easy to be torn,

broken, etc.)

Stacking by crossing

each other

Mention good quality

and spec of bag in PO

QC testing at WH

A. Packaging

A. Packaging

LOSSES GAP ANALYSIS

Loose strapping (not tight)

Improper Jungle box cover (top side only)

Low quality of jungle box

Tight, minimum 4 lanes

with strong plastic

strap.

Cover top include

minimum quarter inside

head.

¼” thickness & water

proof top/cover.

LOSSES GAP ANALYSIS

No full quality control

of packaging

Torn/broken jungle

box

Check palletize

continuously of packaging

(Involve STA and Drlg if

necessary)

Improve handling system

(Warehouse Operator ).

Repair broken pallet

B. Warehousing

B. Moving from Warehouse to STA

LOSSES GAP ANALYSIS

Materials fall down

during transportation

Hydrated material

Use Net to secure

from falling down

Use Tarpaulin to

avoid hydration by

rain water

D. In Staging Area

LOSSES GAP ANALYSIS

• Improper storage

system

Make a good system

for storage (Consult

Warehouse)

Use matting board for

base

Use Tarpaulin to

avoid hydration by

rain water

LOSSES GAP ANALYSIS

Improper lifting

procedure at remote

STA by using Crane

Returned material

from Rig in bad

packaging

Use bar for lifting

Develop SOP for lifting

procedure

Re-palleting at STA

(Req’d tools are

Stretcher, sealer & band,

Pallet, etc..)

Recycling pallets at

location

D. In Staging Area

LOSSES GAP ANALYSIS

Improper storage

system (limited space,

muddy, unprotected,

etc.)

Provide matting

Board for base

Use tarpaulin to

protect material

Provide proper mud

box.

FIFO system

Rigsite

• Provide SOP for

lifting procedure with

Bar.

• Educate crews about

the important of good

pallet

• Regulatory

enforcement

Rigsite

LOSSES GAP ANALYSIS

Improper lifting

procedure by Crane

Stolen/ taken out

pallet and jungle box

before material usage.

Moving between location

LOSSES GAP ANALYSIS

Mud materials

position @ access

road hit by heavy

equipment .

Move out mat. before

Rig moving out (to

STA in OA or to next

well in DSF)

Mud materials are

secured in good pallet

(O/A); or Mud Box

(DSF)

Moving between location

LOSSES GAP ANALYSIS

Mud mat fall down

during moving

Stolen mud mat

Use cargo net.

Never leave

unattended materials

Hand to hand mud

material hand over

TEAM CHARTER

TEAM NAME : MUD MATERIAL LOSSES REDUCTION TEAM

MEMBER : • ESO/BHR ( PROCUREMENT )

• RISMAN JAMIN ( WAREHOUSE )

• HASIRAN ( STAGING AREA )

• ZULFA DENI ( STAGING AREA )

• ASD/SMS (USER)

• YUDO ( MESSINA )

• YANTRI ( BAROID )

• FEZ ( TRANSPORT )

• CB/HJ/Comen ( RIG ADVISORS)

• .GP ( SHE )

TEAM CHARTER

CHAMPION : HR/SMS

GOAL :

– PG = 10 % (Saving $ 1,000,000)

– SG = 5 % (Saving $ 1,500,000)

– Previous looses = 21.1 % ($ 2,100,100 )

MEETING : MONTHLY

REPORTING : 1 X / MONTH

Mud material looses shall be reported every rig release in

Drilling morning report

MUD

MATERIALS

LOSSES

REDUCTION DRILLING

TEAM TARGET

2001

BACK GROUND

LOSSES 21.1 % (1997-1998 Data) = $

2.1 MM

– CONTROLLABLE LOSSES 18.6 % = $

1.86 MM

• Solidified materials = 6.9 %

• Broken packaging = 6.5 %

• Careless = 5.2 %

– Improper usage = 2.5 %

MUD MATERIAL VALUE/YEAR = $ 10 MM

LOSSES GAP ANALYSIS

Improvement

Minimum 5 nails in

every crossed out site

Total wood should be

5 Pcs in bottom, 6 Pcs

in top & 3 Pcs in

Middle.

Low quality of local

product.

– Weak wood pallet

A. Packaging

LOSSES GAP ANALYSIS

Improper stacking

system in jungle box

(parallel)

Low quality of bag

paper (easy to be torn,

broken, etc.)

Stacking by crossing

each other

Mention good quality

and spec of bag in PO

QC testing at WH

A. Packaging

A. Packaging

LOSSES GAP ANALYSIS

Loose strapping (not tight)

Improper Jungle box cover (top side only)

Low quality of jungle box

Tight, minimum 4 lanes

with strong plastic

strap.

Cover top include

minimum quarter inside

head.

¼” thickness & water

proof top/cover.

LOSSES GAP ANALYSIS

No full quality control

of packaging

Torn/broken jungle

box

Check palletize

continuously of packaging

(Involve STA and Drlg if

necessary)

Improve handling system

(Warehouse Operator ).

Repair broken pallet

B. Warehousing

B. Moving from Warehouse to STA

LOSSES GAP ANALYSIS

Materials fall down

during transportation

Hydrated material

Use Net to secure

from falling down

Use Tarpaulin to

avoid hydration by

rain water

D. In Staging Area

LOSSES GAP ANALYSIS

• Improper storage

system

Make a good system

for storage (Consult

Warehouse)

Use matting board for

base

Use Tarpaulin to

avoid hydration by

rain water

LOSSES GAP ANALYSIS

Improper lifting

procedure at remote

STA by using Crane

Returned material

from Rig in bad

packaging

Use bar for lifting

Develop SOP for lifting

procedure

Re-palleting at STA

(Req’d tools are

Stretcher, sealer & band,

Pallet, etc..)

Recycling pallets at

location

D. In Staging Area

LOSSES GAP ANALYSIS

Improper storage

system (limited space,

muddy, unprotected,

etc.)

Provide matting

Board for base

Use tarpaulin to

protect material

Provide proper mud

box.

FIFO system

Rigsite

• Provide SOP for

lifting procedure with

Bar.

• Educate crews about

the important of good

pallet

• Regulatory

enforcement

Rigsite

LOSSES GAP ANALYSIS

Improper lifting

procedure by Crane

Stolen/ taken out

pallet and jungle box

before material usage.

Moving between location

LOSSES GAP ANALYSIS

Mud materials

position @ access

road hit by heavy

equipment .

Move out mat. before

Rig moving out (to

STA in OA or to next

well in DSF)

Mud materials are

secured in good pallet

(O/A); or Mud Box

(DSF)

Moving between location

LOSSES GAP ANALYSIS

Mud mat fall down

during moving

Stolen mud mat

Use cargo net.

Never leave

unattended materials

Hand to hand mud

material hand over

TEAM CHARTER

TEAM NAME : MUD MATERIAL LOSSES REDUCTION TEAM

MEMBER : • ESO/BHR ( PROCUREMENT )

• RISMAN JAMIN ( WAREHOUSE )

• HASIRAN ( STAGING AREA )

• ZULFA DENI ( STAGING AREA )

• ASD/SMS (USER)

• YUDO ( MESSINA )

• YANTRI ( BAROID )

• FEZ ( TRANSPORT )

• CB/HJ/Comen ( RIG ADVISORS)

• .GP ( SHE )

TEAM CHARTER

CHAMPION : HR/SMS

GOAL :

– PG = 10 % (Saving $ 1,000,000)

– SG = 5 % (Saving $ 1,500,000)

– Previous looses = 21.1 % ($ 2,100,100 )

MEETING : MONTHLY

REPORTING : 1 X / MONTH

Mud material looses shall be reported every rig release in

Drilling morning report

CLAY CHEMISTRY

AND INHIBITION

WHAT IS CLAY ?

MINERAL WITH THE PRESENCE OF

WATER AND AGITATION WILL

ADSORB WATER AND BREAK UP TO

COLLOIDAL PARTICLES.

HYDROUS ALUMINUM SILLICATES

COMPOSED OF ALTERNATING

LAYERS OF ALUMINA AND SILICA

TYPE OF CLAYS :

KAOLINITES : Two layers Silica and Alumina. Hydrogen bonding. Non reactive

ILLITES : Three layers, silica is replaced by alumina, non reactive.

CHLORITE : Three layers, separated by Brucite, non reactive.

SMECTITES : Three layers, alumina is replaced by Mg or Fe caused imbalance. Countered by Na or Ca. Reactive clay.

ATTAPULGITE : Non hydrated clay.

CLAY INHIBITION

Inhibited System CAN reduce :

– Gumbo

– Logging Stop

– Bit balling

– Torque and Drag

– High swab and surge pressure

– Hole packed off

– Loss of returns

– Stuck Pipe

Inhibited by adding :

Calcium (Lime or Gypsum)

Salt (K+, Cl-)

Glycol

Silicate

PHPA

Inhibit what ?

Try to prevent …

– Clay Swelling due to

– HYDRATION

Hydration :

Absorption of water by clays that have a

very high surface area

– 100 lb Bentonite has 14 square miles surface

area

Isomorphic substitution with hydrated ions

– Sodium bentonite (Wyoming) cretae the most

viscosity

What is a Hydrated ion ?

Different ions will attract different

amounts of water

Greater the amount of water

– More the hydration or growth in clay particle

size

Bentonite IS NOT required to drill reactive

clay.

Calcium based Fluids :

Inhibited system based on addition either

Ca(OH)2 or CaSO4.2H2O

Used to minimize shale hydration

There are three categories

– High lime ; 5 – 15 ppb excess

– Medium lime; 2.5 – 5 ppb

– Low lime ; 1 – 2.5 ppb

Inhibition ?

Preventing …

– Clay Swelling

• Hydration

– Clay break up

• Dispersion

Hydration can be reduced by :

K+ and Ca2+

Salt (Cl-)

Coating (PHPA, Glycol)

Dispersion :

Clay cuttings can crumble into millions of

particles when they come into contact with

water

Montmorilonite can hydrate and disperse

Other clays will just disperse

– Less surface area

– Little ion exchange

Reducing dispersion :

Water entering shale matrix !

– It weakens non hydrating clays and causes

them to break apart

Can reduce this effect with the correct

INHIBITION mechanism

The Coating Mechanism –

Reducing Dispersion

We can COAT the solid in a protective

shell, preventing water intrusion

PHPA provides a thick viscous coating

surrounds a shale cutting and prevent

dispersion. This is known

ENCAPSULATION

Reducing Dispersion by PHPA

Reducing dispersion by encapsulating clay

by polymer : PHPA, PAC

Preventing hydration and dispersion of

cuttings effective for one trip to surface

Solid removal MUST be effective.

PHPA mechanism !

PHPA fluids INHIBIT the dispersion of

formation solids into drilling fluid system

They do this by forming a PROTECTIVE

COATING that surrounds the cutting and

the wellbore face.

This coating is VISCOUS and

IMPERMIABLE

GLYCOL

Glycol are soluble until a certain temperature is reached, when they CLOUD and fill pore spaces with INSOLUBLE glycol, but they COAT the surface of particle, as well as the surface of wellbore.

Glycol is surfactant (ability to adsorb onto clay surface)

Function best near the cloud point

Glycol Modes of Action :

Below cloud point

– Inhibition of swelling by surface adsorption as individual molecules on clay particle

Above cloud point

– Provides a protective surface coating on the borehole wall and on cuttings near the bottom of the hole

– Acts to limit/prevent filtrate invasion and pressure transmission

Cloud Point Optimisation

The cloud point should be :

– Higher than flow line temperature to avoid phase separation

– Between BHCT and formation and formation temperature beneath the bit

– Adjusted by one of three mechanisms :

• Change in glycol concentration

• Change in salinity

• Change in glycol type

System Application

Drilling reactive shale:

– The cloud point mechanism results in the

deposition of glycol onto cuttings and into the

formation at higher bottom hole temperatures

– As the fluid cools the glycol goes back into

solution and remain in the fluid phase.

CPI MUD SYSTEM

KLM

KCL POLYMER

GEL KOH

XCD POLYMER

KLM (Maltodextrin)

Advantages Disadvantages

Inhibitive by

reducing hydration

of clay (Ca2+

replace Na+)

High solid tolerance

Maltodextrin is non

toxic and non

disperse thinner

Environmentally

friendly (low TDS)

A little bit more

expensive

Temperature

limitation by 300 F

High pH may

cause safety

concerns

A little bit low YP

(but can be

increased by XCD)

How does it work ?

CaOH2 ===== Ca2+ + 2OH-

KOH ======== K+ + OH-

pH is 12-12.5. Soluble calcium is controlled by

filtrate alkalinity of mud. Pf increases less

calcium goes into solution.

Calcium must be controlled with max 400 mg/L

to avoid increasing of viscosity and gel.

Ca(OH)- permanently replaces Na+.

PRINCIPAL ADDITIVES Additive Conc.

, ppb

Function

Bentonite 15-24 Viscosity, Filtration Control

Lime 2-10 Inhibition, Alkalinity Control

Maltodextrin 1-5 Defloculant (max 250 F); Increase

solubility (Ca2+)

Starch 2-6 Filtration Control

Caustic Potash pH 12-

12.5

Alkalinity control, Inhibition

PAC/CMC 0.25-

1.25

Filtration Control, Viscosity

Lignite 2-5 HTHP Filtrate reducer

K-Soltex 2-6 Hole Stabilizer, Inhibition, HTHP filtrate

control

Break over

Bentonite must be prehydrated

Reduce FV to 35-40 sec by adding water

Two circulations

Break over inside casing

Conversion : Lime 5 ppb; Maltodextrin 2-3 ppb; KOH 2 ppb; Lignite 2 ppb.

Lime and Maltodextrin are added together through Hopper. Always add dextrin when adding lime.

Viscosity hump is normal.

Rule of Thumbs

Every 3 cm3 Pm, need 1 ppb lime. Pm is controlled by Lime.

Every 1 cm3 Pf need 1 ppb KOH. Pf is raised by KOH. Raising Pf reduces Ca2+. Pf is raised and Ca2+ is lowered better rheological control and fluid loss.

Add Dextrin 1:1 for thick mud; 1:2 or 3 for thin mud. Never use ratio less than 3 except approved by drilling office.

Add CMC, Dextrid or PAC to control fluid loss.

Rule of Thumb

XCD is only for inclined well to increase viscosity and low end Rheology.

K-Sulphonated asphalt is sparing partner. Use it wisely.

High excess lime when drilling reactive shale and let it drop during drilling sand.

Run SCE all the time; finer screen is better.

To keep Pf constant while adding Lignite, add 1 ppb KOH for every 4 ppb Lignite.

No XCD during breakover

Remember :

“THIS IS NOT KLM MUD

WITHOUT ALAKALINITIES IN

RECOMMENDED RANGE

AND THE PROPER

MALTODEXTRIN USED.”

KCL POLYMER

Inhibition by replacing Na+ with K+

Minimize cutting dispersion by encapsulation

Reduce water inside shale (by presence of Cl-)

K (2.66 A) is more fit to clay lattice structure (2.8 A) compared to Ca.

Shallow shale (reactive) may still swell in K system.

To improve stability, asphalts is used sparingly for hard shale to avoid water filtration.

Excess K+ must be maintained.

Salt Effect

Low salinity Shale vs High Salinity Mud

– Water migrate from shale to mud

– > Stronger Shale or Unstable Shale (dry) if

difference id too high

High salinity Shale vs Low Salinity Mud

– Water migrate from MUD to Shale

– > Soft and mushy Cutting

KCl Polymer

Improve wellbore stability and minimize cutting

dispersion

KCl concentration from 2 % to 5 % is good for

low density and hard formation. Older formation

req’d 3-5%; younger clay req’d up to15 %. May

add form other source of K (K-Soltex)

Require low drill solid concentration

Limited by CPI requirement by 10,000 TDS.

Principal Additives

Additive Conc

.,

ppb

Function

Bentonite 5-15 Viscosity, Filtration Control

KCl 2-5 % Inhibition, source of K+ and Cl-

CFL 3-6 Defloculant

Starch 3-6 Filtration Control

Caustic Potash 0.25-

0.75

Alkalinity control, Inhibition (source

of K+) pH 9.5-10.5

PAC/CMC 0.25-

1.0

Filtration Control, Viscosity

Lignite 2-4 HTHP Filtrate reducer

Other chemicals :

XCD : enhance barite suspension; high YP.

PHPA : partially hydrolyzed

polyacrilamide for encapsulation; hardness

must be lower than 400 mg/L.

Gilsonite : to plug microfracture and bridge

depleted sand

Operating Parameter

Keep polymer concentration in range, if it

is too low, it allows cuttings to disperse

that increases viscosity and addition

polymer will be difficult.

Keep low gravity solid in range (below 6

%) whatever the density. (SCE is critical).

KCL maintenance

Keep LGS below 6 %. Run SCE.

Constantly add PAC and or PHPA since polymer is sheared on bit and removed by shaker (in cutting). 1 ppb PHPA every 100 feet.

Monitor MBT to determine the need of Polymer

Remove solid as quickly as possible.

Contaminants Contami

nant

Indicators Treatment

High Solids Increasing solids,

PV, YP,FC (thick)

Dilution. Improve SCE. Centrifuge

nud

Cement Increasing Pm, Pf,

pH, YP, FL, FV

Minor dilution. Treat with

SAPP/SodBicnat

Poor

product

Erratic mud

properties. Poor

packaging

Document and report to office.

Salt Increasing clorides,

FV, YP, GS, FL.

Kill flow. Convert mud.

Gyp/Anhydr

ite

Increasing Ca2+,

YP, GS, FL.

Decreasing pH, Pm,

Pf

Treat with SAPP, Soda Ash.

Carbonates Increasing Mf, YP,

GS, FV. Decreasing

pH, Pm, Pf.

Treat with Lime. Increase pH with

KOH. Keep LGS in range.

PHPA (dry powder) Problems

Fish eyes

Excessive viscosities

Extensive mixing times and coating

Plugging screen

– Answer : Good Shearing Device

Degraded through bit (high molecular to be

low molecular)

KOH – Gel - Lignite

DSF, Kotabatak, etc.

Purposes

Inhibitive (by the presence of K+)

Low TDS (no chloride)

KOH-Gel-Lignite

Advantages Disadvantages

Inhibitive by reducing

hydration of clay

Economic. Filtration

control by Lignite and

Bentonite

Simple

Thermal stability

Intolerant to

contaminants such as

salt, Ca2+, cement,

solids, carbonates and

anhydrite

Dispersive

Principal Additives

Additive Con

c.,

ppb

Function

Bentonite 15-25 Viscosity, Filtration Control

Lignite 5-8 % Filtrate control; Deflocculation

Caustic Potash 0. 5-

1.5

Alkalinity control, Inhibition

(source of K+) pH 9.5-10.5

PAC/CMC 0.25-

1.0

Filtration Control, Viscosity

Maintenance

LGS below 6 %

K+ is kept in range

Contaminants are kept in acceptable range

Completion/Horizontal

Fluid

KCl-HEC

XCD Polymer

Types of fluids

Clear, solids free brine (HEC-KCl) in DSF

Polymer-viscosified brines with

bridging/weighting agents (XCD Polymer)

KCL-HEC

Advantages

– Solids free

– Inhibitive

– Densified

– Reusable

Disadvantages

– No Fluid Loss Control

– Limited weight

XCD Polymer

Advantages

– Solids free

– Inhibitive

– Densified

– Fluid loss control

– Acid soluble

Disadvantages

– Expensive

Notes

Ground Marble

– 1/3 – 1/7 pore diameter

– Hard /difficult to break

– 13 – 18 ppb Fine; 7-2 ppb Coarse

Materials

– XCD (2 – 2.5 ppb)

– PAC/CMC (4.0 – 5.0 ppb)

– KCl (1-3 %)

– KOH (0.2 – 0.4 ppb)

Properties

High LSRV

6 rpm = 12 –20

FL = < 7 cc

YP = 30-45

pH = 9.5-10

SOLID CONTROL

EQUIPMENT

The most abused

equipment at rig ??

Solids Control

For every 5 % increase

In

Solid removal efficiency

Will

Cut 17 % Mud Cost

Solids Control

$ 45 = 1bbl of fresh mud

75 % efficiency

Mud bill for 12 ¼” $ 200,000

If

85 % efficiency

Mud bill $ 132,000

Why SCE is important ?

Reduce LGS

– Increase life of pump

– Increase ROP

– Maintain good mud properties

Reduce dilution

Reduce Cost

Reduce waste

Etc.

Solids

The life of a drill cutting must be short

Removed as soon as possible (by Shaker)

– Bottoms up Easy

– Twice Hard

– Third times Invisible

Implementation :

Record all SCE performance

– Shaker : coverage

– Hydroclones : Pressure\

– Centrifuge : Mud cut

– Solid removal efficiency

– Efficiency of each SCE

– Mud cuttings ratio

– Equipment performance/failure

Solid tolerance

Mud type is important factor

– KLM ; more tolerant

– KCl Polymer; least tolerant

– XCD Polymer; not at all (free solid)

Drill solid content of 3-4 % by volume

LGS at 6-7 %

Maximum MW without barite is 9.1 ppg

Do not allow solid to degrade

Area of degraded Volume 1 m3 =

– 6 m2 (8 cubes)

– 12 m2 (27 cubes)

– 36 m2 (6216 cubes)

High solids high surface area Limit free water poor Rheology, filter cake, inhibition, more chemicals needed, dilution, etc.

Shale shakers :

The most important SCE

Remove solid before degrade

Effective (as small as possible) screen must be

used

Downstream SCE depend on shaker

Check the vibration patterns

Do not spray directly to screen

Never bypass screen

Hydroclones

75 feet head pressure

Spray type

Frequent checking and cleaning

Calibration by using water

Centrifuge

Decanting system (pouring liquid so

slowly that sediment on bottom

undisturbed)

Remove LGS (5 u)

Ideal SCE

Shakers with 230 mesh (cut point 74 u)

Centrifuge (cut point at 5 u)

Mechanical separation will take out

majority of solid

Dump and Dilution is the LAST tool

Conclusion

Higher pump rate and ROP

Finer screen reduce degradation

Less use of Hydroclones and mud cleaners.

Reduced waste

Reduced cost

Higher drilling efficiency

Improved Rheology due to low LGS

Lower mud viscosities

Reduced Drilling problems

Solids Control System

Cuttings Pile

Surface Volume is 1000 bbls

17-1/2” Hole

Efficiency is 80%

1000 M of Hole

976 bbls drilled solids generated

6.29 bbls/Cu. M

1562 bbls Drilled Solids Discarded

195 bbls Drilled Solids in Mud

9.9% Solids in the Mud

Figure 1: Simple Mass Balance

Solids Control System

Cuttings Pile

17-1/2” Hole

Efficiency is 0%

1000 M of Hole

976 bbls drilled solids generated

No Drilled Solids Discarded

We would need 19,520 bbls of total volume to dilute the drilled solids

to 5%

Worst Case With No

Solids Control

Figure 2: Waste Generation with no solids control

Solids Control System

Cuttings Pile

Surface Volume is 1000 bbls

17-1/2” Hole

1000 M of Hole

976 bbls drilled solids generated

1754 bbls Drilled Solids Discarded

99 bbls Drilled Solids in Mud

at 5% solids

For No Dilution to occur, 90%

efficiency must be achieved

Figure 3: Waste Generation with no dilution

Efficiency Solids Liquids Total

0 0 19,520 19,520

30 586 13,665 14,251

70 1,367 5,857 7,224

90 1,754 1,976 3,730

Using 5% solids limit tolerated in mud

(total volume is 1,976)

Figure 4: Summary of Waste Generation

Lithology

Categories2 4 8 16 32 64 128 250 500 1000

Dispersive Shale 16 34 34 16

Shale 16 34 34 16

Sandstone 16 34 50

Gravel, hard 16 84

Carbonates 16 34 50

Figure 5: Cuttings Distribution

Percentage less than indicated micron size

No Removal Centrifuge Hydrocyclones Shale Shakers

Description of Formation

Percentage

Encountered in

Interval

Description

Percentage

of Solids

Meeting

Description

Dispersive Shale, Clay, Mudstone 40 No Removal 26.4

Shale, Silt, Siltstone 40Remove only

with Centrifuge27.2

Sand, Sandstone 20Remove with

Hydrocyclones23.2

Gravel, Gyp, Pyrite, Granite 0Remove with

Shakers23.2

Others such as Carbonates 0

Figure 6: Example of unconsolidated cuttings distribution

Sand Trap Whole Mud

Hole Size (in) 17.500 Dump Vol (bbls) 50 250

Surf Volume (bbls) 2000 Dump % 20 10

Efficiency (%) 30 Dump Solids (bbls) 10 25

Solids Tolerated (%) 7

Solids Balance

Depth Hole Vol Total Vol Removal Sand Trap* Tolerated Whole Mud Dumped**

1000 1,669.5 3,669.5 500.8 200.0 256.9 711.8

2000 3,339.0 5,339.0 1,001.7 400.0 373.7 1,563.6

3000 5,008.5 7,008.5 1,502.5 600.0 490.6 2,415.3

4000 6,678.0 8,678.0 2,003.4 800.0 607.5 3,267.1

* Sand trap dumped every 50 feet Discard Balance

Removal Sand Trap Tolerated Whole Mud Dumped Total

** Whole mud dumped on average 1,001.7 1,000.0 7,117.8 9,119.5

of every 30 feet 2,003.4 2,000.0 15,635.5 19,638.9

3,005.1 3,000.0 24,153.3 30,158.4

4,006.8 4,000.0 8,678.0 32,671.1 49,355.8

Ratio of discard 7.4

to hole volume

Figure 7: More Detailed Mass Balance

OTHERS

CONTAMINANTS

HOLE STABILITY

BIT BALLING/GUMBO

HOLE CLEANINGS

LOST CIRCULATION

MUD REMOVAL

CONTAMINANTS

SOLIDS

– KEEP LGS BELOW 6 %

CEMENT

– DRILL WITH WATER IF POSSIBLE

– TREAT WITH SODBICNAT

CARBONATES

– MF/PF RATIO IS HIGH

– PH DROP

– HIGH VISCOSITY, GEL, FL, ETC.

– TREAT WITH LIME

MANAGE SOLIDS CONTENT

LOOK FOR CONTAMINATION ALL THE TIME

TEST FOR CARBONATES ROUTINELY

HAVE STRATEGY FOR DRILLING CEMENT

KEEP MUD PROPERTIES UNDER CONTROL

HAVE CHEMICALS TRETAMENT AT RIG

HOLE INSTABILITY

Caused by insitu stress independent of mud

chemistry BUT effected by mud properties

Important mud properties (primary weapon to

overcome hole instability) :

– Density

– Fluid loss

– Filter cake properties

– KCl is not recommended for brittle shale since Cl-

will suck out water

BIT BALLING What is the process ?

– Bit cut dry rock Interaction with mud cuttings move from dry to plastic to wet.

– Cutting in plastic state cause balling

The bit balling severity :

– Formation dispersability

– Free water content

– Polymer content

– Solids content

To solve :

– Add more free water

– Reduce polymer content (increase water loss)

– Reduce solid content

– Add lubricant

– Good hydraulic and bit design

LOST CIRCULATIONS

PREVENTION

– LCM in mud while drilling

CURING

– Spot LCM on bottom, wait for healing, try several 2-3 times with bigger volume

CONSIDER TO USE NON DAMAGING LCM

DISCUSS WITH OFFICE

MUD REMOVAL FOR

CEMENTING

Minimum twice bottom up

Sweep with pills

Reduce PV, YP

Good hole cleaning

Water ahead if possible (6 minutes contact time)

Keep pipe moving

Apply recommended cementing practices

HOLE CLEANINGS

Improved by :

– Optimum flow rate

– Viscosity especially 6 rpm, 3 rpm and LSRV

– Rate of penetration

– Hole cleaning pills

• High viscosity

• High density

• Low viscosity

– Pipe rotation, Drill pipe eccentricity, Mud weight, Cutting density, Cutting size

– “ ARE WE CLEANING THE HOLE ?”

MUD REPORT

DIMS (NEW

DRILLING

REPORTING

SYSTEM)

Mud Report

Subjects to covered are :

– Volume Control Data

– Chemistry

– Rheology

– Geology

– Cost

– Waste

– SCE

– Treatment

– Evaluation

The Most Important Thing :

Mud Engineer COMMENT

Comments :

Should direct the reader to the important

data

Make connection between what happened

and what is about to occur

Should demonstrate proactive thinking

Honestly, no hidden agenda.

Rheology :

Must be tested (partially) every hour or

less and record in Mud Engineer book.

Must be reported for three complete test

per day (every 8 hours or in critical

operation)

Do not report only the good/ideal mud

properties.

What is the important stuff ?

Footage drilled

SCE performance (write down completely)

Product concentration and performance

Hole cleaning

Cuttings condition

Cuttings volume (Mud Cutting Ratio = 5-7)

Waste generated

Properties trend tracking

Contaminants, etc

Mud Report (DIMS)

Mud Engineer must enter report

completely into DIMS computer

DIMS has complete Mud report (you have

to be patient and diligent)