171137266 Welcome to Drilling Fluid Seminar CPI
description
Transcript of 171137266 Welcome to Drilling Fluid Seminar CPI
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)