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Primary funding is provided by

The SPE Foundation through member donations and a contribution from Offshore Europe

The Society is grateful to those companies that allow their professionals to serve as lecturers

Additional support provided by AIME

Society of Petroleum Engineers

Distinguished Lecturer Programwww.spe.org/dl 1

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Lunskoye Big Bore Gas Wells -Maximising Gas, Minimising Sand

Mike GunninghamSakhalin Energy Investment Company

Society of Petroleum Engineers

Distinguished Lecturer Programwww.spe.org/dl

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Presentation Overview

• Introduction Sakhalin II Project

• Lunskoye Field Overview

• Overview of Original Completion Design

• New Sandface Completion Selection

• New Completion Design

• Quantitative Risk Assessment and Sand Management Plan

• Conclusions

4

Where is Sakhalin?

Sakhalin

You are here

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• Piltun B platform (70k BOPD)

• Astokh year round production (70k BOPD).

• Lunskoye A platform (1800 MMscf/d & 45k BCPD).

• Onshore processing facility.

• Oil and gas pipelines.

• LNG plant (9.6 MMTPA) & Oil Export Terminal.

Sakhalin II Development

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Every Aspect is HUGE! .. $22 billion

$100/second Spend

1st LNG Plant in Russia2 x 4.8 million tonnes p.a.

800km Oil & Gas Pipelines

Environment

20,000+ People, 60x106 hrs p.a.

A Mega-Project in a Frontier Environment

2 New Platforms

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• Discovered in 1984 and appraised with 7 wells

• Excellent gas reservoir with thin oil rim

• GIIP 18.6 Tcf, • STOIIP 931 MMbbl

• One platform (Lun-A) can sustain 20 years production plateau for

two LNG trains.

II

III

IV

I

II

III

IV

V

VI

Lunskoye Gas Field

8

Lunskoye Field – Formation Data

Aver Porosity = 25%, Perm = 150 – 1,200 mD,

d50 = 55-357 (Av = 167µm) Fines = 7-42 (23%)

Lun - 1 , 3 , 4 & 6 Core Data

Cumulative Weight -vs- Particle Size

0

10

20

30

40

50

60

70

80

90

100

110100100010000

Particle Size [micron]

Cu

mu

lati

ve

We

igh

t [%

]

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Initial Gas Well Design, 2002

• 9-5/8” x 7” 13Cr tapered tubing, with Pre-Drilled Liner or Slotted Liner completion in open hole.

• Sand expected to be produced and managed, and retrofit sand control as required.

• Topsides designed for sand production (0.5 lbs/MMscf), with 1/2 tonne sand/day expected

10

Follow-Up Work in 2002-2004

• Value Engineering of Topsides,

– Sand handling equipment removed

– Reduced 14” flowlines to 12”(erosion critical)

– No test separator

• Acceleration of Gas Sales

– No float in drilling schedule to enable retrofit sand control.

• In 2004: High rate gas wells & sand expected, with:

– No sand exclusion downhole,

– Minimal surface sand handling capability.

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2004, Openhole Sand Estimate

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What happens if a well produces sand?

If this happens on Lunskoye: A delay in the time to reach Plateau production would be 4-6 months minimum.

Water-Condensate

Separator

(Courtesy of A. Kooijman)Particle Size (microns)

9.5/8”Tubing

7”Tubing

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Bare

foo

t

Pre

-dri

lled

lin

er

Slo

tted

Lin

er

Sta

nd

Alo

ne

Scre

en

Cased

an

d

Perf

ora

ted

OH

ES

S

OH

Gra

vel

Pa

ck

Overall Score

ReliabilityInstallation / Do-abilityCapacityCostHSE

Back to the Drawing Board: Sand Face Completion Selection

Cased & Per forat edCased & Per forat edCased & Per forat edCased & Per forat ed

Open Hole Gravel Open Hole Gravel Open Hole Gravel Open Hole Gravel PackPackPackPack

Expandable Slot t ed Expandable Slot t ed Expandable Slot t ed Expandable Slot t ed ScreenScreenScreenScreenSt andalone ScreenSt andalone ScreenSt andalone ScreenSt andalone Screen

Slot t ed LinerSlot t ed LinerSlot t ed LinerSlot t ed Liner

I n t ernal Gravel PackI n t ernal Gravel PackI n t ernal Gravel PackI n t ernal Gravel Pack

PrePrePrePre---- Dr i l led LinerDr i l led LinerDr i l led LinerDr i l led Liner

Open HoleOpen HoleOpen HoleOpen Hole

SPE 88493

Cased & Per forat edCased & Per forat edCased & Per forat edCased & Per forat ed

Open Hole Gravel Open Hole Gravel Open Hole Gravel Open Hole Gravel PackPackPackPack

Expandable Slot t ed Expandable Slot t ed Expandable Slot t ed Expandable Slot t ed ScreenScreenScreenScreenSt andalone ScreenSt andalone ScreenSt andalone ScreenSt andalone Screen

Slot t ed LinerSlot t ed LinerSlot t ed LinerSlot t ed Liner

I n t ernal Gravel PackI n t ernal Gravel PackI n t ernal Gravel PackI n t ernal Gravel Pack

PrePrePrePre---- Dr i l led LinerDr i l led LinerDr i l led LinerDr i l led Liner

Open HoleOpen HoleOpen HoleOpen Hole

SPE 88493

But C&P has no screen/filter to stop sand …

…. so how much sand will be produced?

…. how much gas production?

Worst OptionPossible OptionGood Option

Cased & Perforated

Open Hole Gravel Pack

Expandable Sandscreen

Standalone Screen

Slotted Liner

Internal Gravel pack

Predrilled Liner

Barefoot

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Openhole Vs Cased and Perforated: Sand Prediction

Openhole Cased & Perforated

Sand Production is expected to be delayed (with smaller volumes) with cased and perforated completions compared to openhole completions

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2004 Prediction Calibrations: Cased & Perforated

• Drill Stem Tests from Lun-7 observed no sand

• Successfully predicted (Blind)

• Sand failure predictions also showed sand would not be expected in the DSTs performed on other wells –consistent with the observations.

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Productivity Predictions: Lun-501

• Development well trajectories changed from vertical to inclined to increase reservoir exposure

• Completion sizes 8 ½” and 12 ¼” open hole considered

0.0

100.0

200.0

300.0

400.0

500.0

600.0

700.0

800.0

900.0

8 1/2" 12 1/4" with 9 5/8" 12 1/4" with 10 3/4"

Op

tim

al

Init

ial

Pro

du

cti

on

(m

mscf/

d)

Cased and Perforated (100%)

Open Hole Gravel Pack (0 skin)

Expandable Sand Screen

Lunskoye 501

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Downhole: Sandface Completion Comparison

Limited track record for high rate gas wells

No Water Shut Off capability

8 ½” hole only

Downhole sand control

Expandable Sand Screen

Very difficult to achieve in winter

Lower Productivity

Costly & Complex installation

No Water Shut Off capability

Downhole sand control

Openhole Gravel Pack

Sand production later in field lifeRobust, Productive

Water Shut Off capability

Cased & Perforated

ConsProsSand face completion

Conclusion of sand study - use C&P and make detailed contingency design for ESS/OHGP.

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Optimising Cased & Perforated Completion

• Development well geology estimated for 2m AHD intervals discretisation.

• 400 inflow intervals/well (~2 to 3m AHD).

• Sand Prediction gives failed intervals: these are not perforated.

Gas Wells 1-3 Gas Wells 4-7

9 5/8”Liner

13 3/8”Casing

9 5/8”Tubing

9 5/8”Liner

13 3/8”Casing

9 5/8”Tubing

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Example of Petrel Discretisation of Daghinsky

2m Intervals

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Impact on Initial Production with Selective Perforation

2040

2035

2030

2017, 2020

& 2025

2040

2035

2030

2017, 2020

& 2025

� Selective perforating based on sand free production until 2025

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QRA: Quantitative Risk Analysis

• Integrated Team reviewed LUN-A system

• Facilities designed to manage sand production

• QRA systematically evaluates the residual risks for different phases of the production

• Recommendations made with minimal or no additional costs (procedural), to further reduce residual risk to facilities.

Phase 4 - Production

Xmas Tree

Production

Separator

Flare KO Drum

Flare tip

Lit by propane

HIPPS Valve

Pig Launcher

Produced Water System

(De-gasser, Pumps,

Manifold)

Condensate

Gas

MEG

LM

UM

Choke

K

CV

Start-up

header

Production

header

Other

wellsOther

wells

ME

G

Cyclone

6” Well

Clean Up

Header

6” Grayloc Flowline

CRI / Pits

SD

Other

Wellbay

4”

Flowline

Heaters

Upper

Completion

Sandface

Completion

Near

Wellbore

WV

WCU Separator

System

Solids

Recovery

System

Erosion Probe W1

Erosion Probe W2

Erosion Probe P1

Erosion Probe P2

Sand

Detector

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Mitigation Measures to Reduce Impact of Sand Production

Example• 12” Flowline

• Erode until detected

• Remedial Options– Maximise use

Well Clean Up Unit

– Small bean Up steps

– Use clamp on sand detector

– Non destructive testing

0

10

20

30

40

50

60

70

80

.Failure Modes

Ris

k R

an

kin

g

Phase 1

Phase 2

Phase 3

Phase 4

Phases 6&7

Phase 8 choke manifold leaking

choke leaking

liner split

20" production header leak

production separator fills

12" flowline leaking

12" flowline thinned

red-flag threshold

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Remedial Completion Options

3 8 9 10

Ce

me

nt

sq

ue

eze

& d

rill

ou

t

Ca

se

d H

ole

ES

S (

WC

S)

Wir

eli

ne

Co

nv

ey

ed

Sc

ree

n

Pa

tch

(G

en

eri

c)

(W/L

& C

T)

Selection criteria

Through Tubing

Max Running OD<5.75"

ID restriction post deployment

Metallurgy CRA, 13Cr or higher

Deployment (W/L, CT, DP, W/O) CT DP W/L

Length Range

Live Deployment? (Y/N)

Collapse Rating (psi)

Mid interval sand production

Bottom sand production

Sand location unknown

Whole section sanding

W/L & CT & Blanks

100m???

W/L blanks 4-5mW/L blanks 4-5mW/L & CTCT + SPT

3m/treatment

WL & CT

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Screenless

Infl

ata

ble

Plu

g

1

Re

-Pe

rfo

rate

Str

ad

dle

Pa

ck

ers

Ce

me

nt

Plu

g

Me

ch

an

ica

l P

lug

Sa

nd

Co

ns

oli

da

tio

n/P

oly

me

r S

hu

t-o

ff

Interval Isolation

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Mid-Reservoir Interval Isolation

2 7

SandAboveLimit

Yes

No

Bean-back

SandAboveLimit

Yes

No

ProductionAdequate

No Yes RunEconomics

ProduceCloselyMonitor

RemedialMeasures

CloselyMonitor

SandAboveLimit

Yes

No

SandAboveLimit

SandAboveLimit

Yes

No

Yes

No

Bean-back

SandAboveLimit

Yes

Bean-back

SandAboveLimit

Yes

NoNo

ProductionAdequate

No Yes RunEconomics

ProductionAdequate

No Yes RunEconomics

ProduceCloselyMonitor

ProduceCloselyMonitor

RemedialMeasures

CloselyMonitor

RemedialMeasures

CloselyMonitor

Remedial Measures Selection Matrix

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Sand Management Plan

• Lunskoye Sand Management Plan:

– Completion Design

– Quantitative Risk Assessment

– Monitoring

– Roles & Responsibilities

– Contingency Planning

• Apply other operator’s experience

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The $22 Billion Question?

Did it work?

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Gas To OPF

LA503

LA517

Test Sep Flare KO

Liquids Pump

Cyclonic De-sander

Steam H.E.

Train 1 Sep

Train 2 Sep

HIPPS

Clean Up Manifold

Prod Manifold North

Prod Manifold South

Boom Flare

Pig Launchers

Riser Valves

Multiphase Export Lines To OPF

Start Up Header

Schlumberger Well Clean Up Unit (WCU)

LUN-A Start Up Configuration

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Lunskoye Clean Up, Dec 2008

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Bean Up Summary

• No incidents or accidents

• Each well delivers:

– 350 MMscf/d or 10 Mln.m3/d gas

– Practically no sand seen (half a cup)

• Lunskoye gas wells are:

– Russia’s largest gas wells

– Largest offshore gas wells in the world

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Conclusions

• Pre-Drilled Liner produced too much sand

• New Sand Failure Prediction Tool predicts onset of sand & quantifies volumes

• Preferred new completion design is Cased and Selectively Perforated

– Defer sand production to 2025+

– Sand levels lower and more manageable

• Quantitative Risk Assessment to address risk

• Lunskoye Sand Management Plan to manage risk

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Final Words

• Cased & Selectively Perforated Wells deliver World Class Performance

– Maximise gas production

– Minimise sand production

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Acknowledgements

To those that did the work…

• David Brown, Jeroen Webers, Christoph Zerbst (Sakhalin Energy), Philippe Brassart, Hamed Subhi & Tony Addis (Shell)

And to those that paid for it….the Shareholders

• Gazprom

• Shell

• Mitsui

• Mitsubishi

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Questions?

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References

• SPE 116713: Sand Quantification: The Impact on Sandface Completion Selection and Design, Facilities Design and Risk Evaluation

• SPE 112099: Applying Sand Management Process on the Lunskoye High Gas-Rate Platform Using Quantitative Risk Assessment

• SPE 114805: The Integrated Use of New Technology in the Development of the Sakhalin II Project