Oilfield Services

INDUSTRIAL INTERNSHIP PRESENTATION

Scomi Oiltools Overseas (M), Khartoum , Sudan

AHMAD BAKRI BIN ZUBIRPetroleum Engineering | 9058

Universiti Teknologi Petronas

Plant Supervisor

Mr. Ramy SragDF Operational Manager

Date: 4th January 2010Time: 2.30 pm

Oilfield Services

• Industrial internship objectives

• Host company profile

• Drilling fluids

• Internship assignments, activities and site

operations

• Lesson learned and experience gained

• Discussion & recommendation

• Conclusion

OUTLINE

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• Integrate theory with practice & apply theoretical knowledge in

industrial application.

• Introduce student to work culture and industrial practices

• Expose student to potential employers

• Importance Health, Safety & environment (HSE) at workplace

• To make interns be acquainted with water-based mud systems

used in Scomi Oiltools in Sudan operations and contribute the

company by assisting on-site field engineers.

INTERNSHIP OBJECTIVES

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• Scomi Oiltools (formerly known as KMC Oiltools), a subsidiary of Scomi Group.

• One of the world’s leading providers of innovative high performance drilling fluids and drilling waste management services.

• Scomi Oiltools had established overseas operations in Sudan in 2003 with GNPOC and in 2005 with WNPOC

• Involved in three core division – drilling fluids, drilling waste management and oilfield product distribution

• Worldwide operations coverage of drilling fluid operations - extends from Asia region to USA

HOST COMPANY PROFILE

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• Fluids that aid the production and removal of cuttings from the borehole

• Differ widely in their chemical compositions.

• Also known as mud.

DRILLING FLUIDSIntroduction

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DRILLING FLUIDSFunctions

Maintainborehole stability

Controlformationpressure

Minimizeloss of fluid

to formation

Transport & removecuttings

from the well Cool, lubricatethe drill string & BHA

Hydraulichorse power

to the bit

Seal Permeable formationPrimary

Additional

Suspend cuttings- Static condition

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DRILLING FLUIDSMud Circulation

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1. Fluid Phase (water or oil)2. Solids (to give desired mud property)

• Inactive solids – do not react with mud (i.e barite) to give mud weight• Active solids – clays that react with the water (i.e bentonite) to give viscosity.

3. Additives (to give desired mud property)• Polymers and chemicals to control viscosity, yield point, fluid loss, pH,

controls

DRILLING FLUIDSMud Content

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1. WATER BASED MUD

DRILLING FLUIDSMud Types

• Continuous phase is water• Main disadvantage – causes shale

instability• Lower cost• Types of WBM used in Scomi

Oiltools Sudan Operations -• Non-inhibitive (gel)• Inhibitive (KCl)• Polymer (KCl PHPA, KCl

silicate)

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2. OIL BASED MUD

DRILLING FLUIDSMud Types

• Continous phase is oil• Advantage

• Does not react with shales• Good lubrication to BHA• Undamaging mud – very low formation

damage if any• Excellent wellbore stability• Usually used in HTHP wells

• Disadvantage• Environmental impacts (toxic)• Much more expensive than WBM• Danger threat to rig workers - slippery

Oilfield Services

DRILLING FLUIDSChemical & Polymer Additives

• Soda Ash – Hardness reducer• Sodium Bicarbonate – Hardness & pH reducer• Caustic Soda – Alkalinity control (increases pH)• Bentonite – Viscosifier• PAC-R & PAC-UL (organic polymer) – Viscosity & Fluid loss

control• Starch – Fluid loss control• Xanthan gum – Viscosifier and LSRV (low shear rate viscosifier)• Calcium Carbonate – Bridging & weighting agent• Barite – Weighting agent

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ACTIVITIES, TASKS & ASSIGNMENTS

Office/HQ

Warehouse

• HSE course• Learnt about drilling fluids• Discussion with SV and other mud engineers• Revision of mud recaps• Prepared data tables of wells drilled during 2008 & 2009• Prepared the mud lab• Assisted in re-checking chemical invoices

• Attended GNPOC HSE meeting • Briefly learnt about inventory & logistics management• Learnt more about drilling fluids with the warehouse SV

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ACTIVITIES, TASKS & ASSIGNMENTS

Site Operation

• Have been to 2 well sites:• Azraq N-1 (Gel Mud & KCl polymer mud) - (43 days)• Joknyang NE-1 (KCl PHPA mud) - (28 days)

• Given the following tasks:• Perform the duty of back-up mud engineer• Maintain and operate the solids control equipments• Mixed new mud & hi-vis mud• Assisted during cementing jobs• Make mud tests• Chemical inventory management & repacking• Learnt about good drilling practices

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SITE OPERATIONS

Solids control equipments

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SITE OPERATIONS

Solids control equipments

• Sand Trap• Pit tank located under shale

shakers• Mud flow rate is slow• Settling rate – function of:

• SG of particle• Density & viscosity of mud• Type flow regime & residence

time in pit• Periodically checks the sand trap

to see the sand level• If level of sand is high – dump the

sand trap – 40 -50bbls

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SITE OPERATIONS

Solids control equipments

• Shale Shakers• Most important SCE• Mud flows - return line to shale shakers• Vibrating Screens remove drill cuttings• Solids that are bigger than screen

size are conveyed off the screen• Size of solids discarded are dependant

upon the opening size of the screens (120 microns, 170 microns, 200 microns)

Oilfield Services

SITE OPERATIONS

Solids control equipments

• Shale Shakers: Cuttings Observation & Maintenance

• When drilling shale zones, good inhibited mud should produce rounded, pebble size cuttings & dry in the inside

• Larger than average & angular cuttings are cavings • Poorly inhibited mud/ Gel mud: Fine & sticky solids blind the screens. Results in mud overflow. To overcome:

• Increase the inclination of the screens.• Clean the screen using water jet nozzle

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SITE OPERATIONS

Solids control equipments• Shale Shakers: Cuttings Observation & Maintenances

Angular cuttings : Indication of cavings

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SITE OPERATIONS

Solids control equipments• Shale Shakers: Cuttings Observation & Maintenances

Usage of gel mud: Sticky, uninhibited cuttings, Mud Overflow

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SITE OPERATIONS

Solids control equipments• Shale Shakers: Maintenances

• Helped changing torn-out/broken screens• Torn screens allow larger solids to pass through screen – Shale shaker not effective• Causes: - Usual wear and tear of screens

- Improper installation of screens – premature defects - low quality screen

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SITE OPERATIONS

Solids control equipments

• Desilter• Removes silts -> hydrocyclone• Smaller size than desander• Can handle up to 75 GPM of mud flow• Remove particles: 15-30 microns

• Desander• Removes sand –> hydrocyclone • Can handle up to 500 GPM of mud flow• Remove particles: 45-74 microns

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SITE OPERATIONS

Solids control equipments• Mud Cleaners• Combination of desander and desilter mounted over a screening device.

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SITE OPERATIONS

Solids control equipments• The centrifuge• Separate solids by increasing the centrifugal force• Removal up to 2-5 micron• Bowl rotates between 2000-4000rpm• Capacity 50-250gpm• Useful for processing weighted fluid• Faster rotation to remove lower SG solids (silts)• Slower rotation to remove higher SG solids (barite)• Barite recovery process:

• 1st centrifuge = Separate barite, liquid moves to the 2nd centrifuge• 2nd centrifuge = removes silt and return liquid portion back to mud

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SITE OPERATIONS

Solids control equipments

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SITE OPERATIONS

Mixing new mud (in premix tank)1. Water (as required)2. Soda Ash (0.5 ppb)3. Caustic Soda (0.4 ppb) - pH 8.5-9.54. Potassium Chloride (KCl) (5-10 ppb)5. Polymers for Fluid Loss control and

rheology6. Barite (weighting agent) for mud density

requirement (as required)

Premix Tank 1 Premix Tank 2

Pill Tank

Suction Tank 1

Suction Tank 2

Centrifuge Tank

Desilter Tank

Desander Tank

Sand Trap

Trip Tank

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SITE OPERATIONS

Pumping Hi-Vis & Slug

• Slug is used to displace mud in stands of pipes prior POOH• Hi-Vis is pumped down hole to suspend cutting during long hours of

non-circulation and pipe rotation• Hi-Vis sweep is performed to lift cuttings downhole (increase efficiency of hole cleaning)

• Transfer active mud to pill tank (40bbls)• Increase weight and viscosity by addition of barite and KMC-Zan

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SITE OPERATIONS

Assisted cementing jobs

• Weighting up cement• Pumping the spacer fluid (50 bbl water) to displace mud• Treating mud with sodium bicarbonate (decrease hardness & pH)

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SITE OPERATIONS

Dump or Dilute

- Drilled solids content is high (PV & sand trap) Dump- Mud Weight is high but drilled solids content is low Dilute

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SITE OPERATIONS

Other chemical usage & observations• Drilling detergent – to prevent bit balling

• Biocide – Prevent bacterias from spoiling the polymers

• Caustic Soda – Used to increase pH (alkalinity) after long hours of no mud circulation

• Washpipe – leak in drillstring or BHA – eventually lead to fishing

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FLUID SYSTEMS

• Bentonite Mud (Gel

Mud)• No inhibition

• Lower cost

• Suitable for surface drilling

• High carrying capacity

• Deep hole - Hole problems

• pH 8-9

• KCl Polymer• Moderately reactive shale

• Cation exchange of Potassium ions with clay

• High inhibition – reduce swelling/hydration

• Upgradable to Sodium Silicate mud

• KCl depletes over time

• pH 8.5-9.5

• KCl Sodium Silicate• Coats the cuttings and wellbore with a thin

layer of silicate

• Suitable for reactive shale

• KCl & Silicate deplete over time

• Higher cost

• Protection against stuck pipe & balling

• Enhanced inhibition

• Ensures mechanical stability (micro

fractures & unconsolidated formation)

• pH 11.5-12.5

Oilfield Services

MUD TESTING & EQUIPMENTS

Mud Weight test

• Mud balance to determine the mud weight (in lb/gal) as specified by

program

• Place mud in mud cup

• Rider – adjusted along the graduated scale with guidance of bubble vial

• Accuracy +/- 0.1 ppg

Oilfield Services

MUD TESTING & EQUIPMENTS

Funnel Viscosity

• Marsh Funnel & beaker (1 quart)

• Quick guide whether mud is thickening or

thinning (YP)

• Reading is influenced by gelation and

density of mud

• Calibration – water at 21 celcius (70

fahrenheit) = 26 sec/qt

Oilfield Services

MUD TESTING & EQUIPMENTS

Rheology Test: PV & YP

• 6 speed viscometer • For determining the values of YP & PV

• Rotor sleeve rotates at constant velocity

(speed control by the switching gears)

• Produce torque to inner bob –

displacement of bob provide the reading

(lb/sq.ft)

• 600,300,200,100,6,3 rpm speeds

• PV = 600rpm – 300rpm

• YP = 300 rpm - PV

Oilfield Services

MUD TESTING & EQUIPMENTS

Rheology Test: Gel Strength

• 10 seconds / 10 minutes reading

• 10 sec 600rpm for 30secs, leave for 10

secs, read 10-sec gel at 3rpm

• 10 min 600rpm for 30secs, leave

undisturbed for 10mins, take reading at

3rpm

• Good gel is needed to suspend cuttings

• Wide divergence between 10secs and

10mins reading indicate colloidal build up

Oilfield Services

MUD TESTING & EQUIPMENTS

API filtrate• To know milliliters of filtrate lost under 100psi

pressure • Procedure:

• 100psi applied to the column of pressure cell using air compressor

• 3 ½ inch diameter of filter paper placed in the bottom of pressure cell (build up of filter cake)

• Amount of filtrate collected for 30 minutes, (ml/30min)

1) Low filtrate volume Thinner cakes, good fluid loss control in mud

2) High filtrate volume Thicker cake, must treat mud with PAC-R, PAC-UL and starch to minimize fluid loss

• Thick mud cakes leads to differentially stuck pipes

Oilfield Services

MUD TESTING & EQUIPMENTS

pH, sand content & hardness test• pH test – uses pH paper to measure pH of filtrate

• Sand content – Uses sand screen set kit to determine sand content in mud

• Hardness test - To measure hardness of filtrate water. It is not good if the water is too hard, as polymer reactions cannot take place effectively. Chemicals needed are, 1 ml filtrate, a few drops of ammonia 30%, versanate hardness indicator, and EDTA (slowly releasing it). Mixture changes color from purple to wine red.

Oilfield Services

MUD TESTING & EQUIPMENTS

KCl & Chloride Test• KCl Test - KCl Content determination by sodium perchlorate

1) Precipitating potassium 2) Centrifuging the precipitate3) Compare the volume of precipitate over the graph to determine amount

of KCl content left in mud

• Chloride test - To know the concentration of chloride in the mud. Chemicals needed are 1 ml filtrate, a few drops of yellow chloride indicator and silver nitrate 0.282N (slowly releasing it). Mixture changes color from yellow to red.

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DISCUSSION

Lessons learnt

Recommendation

Problems &

Challenges

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DISCUSSION

Problem and Challenges

System understandings

& Field experience

Communication

Challenging location of wellsites

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DISCUSSION

Lesson LearntCommunic

ation skills

Application of engineering knowledge

Hardworking and self

learning

Adaptation to new

environments

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DISCUSSION

Recommendations

•More detailed discussion between UTP and host company in meeting the expectation of this Internship Program•Set Key Performance Indicator (KPI) based on specific programs

UTP

•Great internship experience•Should take more internship from UTP – Sudanese & Malaysians.

Scomi Oiltools

Oilfield Services

• Industrial internship objectives

• Host company profile

• Drilling fluids

• Internship assignments, activities and site

operations

• Lesson learned and experience gained

• Discussion & recommendation

• Conclusion

RECAP

Oilfield Services

• Expose students to real-life working experience, culture and industrial practices.

• Practice theory learned during studies into working environment.

• Students could gain the opportunity to work directly with industrial practitioners

• Acquaint UTP students especially from PE department with the Petroleum Industry

CONCLUSION

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THANK YOU

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Q & A