The 3rd Workshop of the Cambodia PPM Case Study

Development of Donghae-1Gas Field, Offshore Korea

30 March 2004KIGAM (Korea Institute of Geoscience & Mineral Resources)

KNOC (Korea National Oil Corporation)

The 3rd Workshop of the Cambodia PPM Case StudyKorea Institute of Geoscience

and Mineral Resources

Donghae-1 Gas Field

V V-2V-1

B1

B2

B3B4

B5

Water Depth

Distance from Shore

Gorae V

Gorae V-1

Gorae V-2

Sectional View

The 3rd Workshop of the Cambodia PPM Case StudyKorea Institute of Geoscience

and Mineral Resources

DEVELOPMENT OF DONGHAE-1

Geophysical Prospecting

Exploration Well

Data Processing

& Interpretation

FailureDiscovery

of Gas Field

Appraisal Well

Reserve Estimation

Feasibility Study

Commercial

Development

Economic Feasibility

Development Options

Location of Appraisal Well

Preliminary Feasibility Study

The 3rd Workshop of the Cambodia PPM Case StudyKorea Institute of Geoscience

and Mineral Resources

Table of Presentation

• Introduction• Deliverability Analysis• Development Options• Compositional Simulation• Production Optimization• Production Facilities• Concluding Remarks

The 3rd Workshop of the Cambodia PPM Case StudyKorea Institute of Geoscience

and Mineral Resources

DELIVERABILITY ANALYSIS

Modified

Isochronal

Test

Flow After

Flow

Test

Deliverability

Test

103.88366.14B4V DST#2

42.37843.44B2V-2 DST#3

92.78014.07B4V-2 DST#1

137.47868.44B3, B4V-1 DST#2

28.37923.85B3V-2 DST#2

48.47781.27B2V-1 DST#3

51.77685.83B2V DST#3

Net Pay

Thickness

(ft)

Gauge

Depth (ft)

Target

LayerDST No.

• DST & Deliverability Analysis DST Data

Reservoir Properties

Horner Plot

Type Curve Matching

Radius of Investigation

Wellbore Storage Effect

Estimation of Deliverability

The 3rd Workshop of the Cambodia PPM Case StudyKorea Institute of Geoscience

and Mineral Resources

DELIVERABILITY ANALYSIS

Transient Test

Deliverability Test

0 20 40 603000

3200

3400

3600

3800

0

10

20

30

40

ELAPSED TIME (hrs)

PR

OD

UC

TIO

N R

AT

E (

MM

SC

FD

)

PR

ES

SU

RE

(p

si)

TRANSIENT PRESSURE TEST

44 48 52 56 603200

3300

3400

3500

3600

0

10

20

30

40

PR

OD

UC

TIO

N R

AT

E (

MM

SC

FD

)

PR

ES

SU

RE

(p

si)

ELAPSED TIME (hrs)1 101 102

10-1

1

101

C

1n

Flow After Flow Test

Stabilized

Deliverability

Line

Actual Data

qsc = C(pR2 – pwf

2)n

qsc (MMSCFD)

DELIVERABILITY TEST

Wellbore storage effect is not

significant

1.07e-4C4.50s

152.80AOF (MMSCFD)

0.0021tws (hrs)

3608.79p* (psi)

Late time deviation: shale effect 853.92r inv. (ft)

0.865n37.49k (md)

Deliverability TestPressure Transient Test

The 3rd Workshop of the Cambodia PPM Case StudyKorea Institute of Geoscience

and Mineral Resources

DELIVERABILITY ANALYSIS

• EExcellent agreements between type curve matching

method and Horner method

Permeability: moderately ranged from 23.0 to 65.3 md

Skin factor: 4.64 to 21

AOF: 21.2 to 152.8 MMSCFD

• SSubstantial productivity: more than 60 MMSCFDV-2 (DST #2): 21.2 MMSCFD

The 3rd Workshop of the Cambodia PPM Case StudyKorea Institute of Geoscience

and Mineral Resources

DEVELOPMENT OPTIONS

• Engineering Data Reserve, Rock and Fluid Properties

• Gas Sales SpecificationsMarketplace, Supply, Price

• Design Specifications Temperature, Pressure, Processing Capacity of Facilities

• Environmental Data Weather, Subsea Condition

• Economic ParametersCost of Capital, Operating Expenses

The 3rd Workshop of the Cambodia PPM Case StudyKorea Institute of Geoscience

and Mineral Resources

DEVELOPMENT OPTIONS

• 1st Stage : Identification of All Feasible Development Options

Substructure System Type

Drilling Methods

• 2nd Stage : Selection of Favorable ProcessOption Screening

24 Production Options

• 3rd Stage : Optimized Development ConceptSelection of Preferable Process Option

The 3rd Workshop of the Cambodia PPM Case StudyKorea Institute of Geoscience

and Mineral Resources

DEVELOPMENT OPTIONS

Development Option

Drilling Substructure Processing & Export

Permanent

Platform

Facilities

Tender

Assist

Drilling

Mobile

Rig

Drilled

Floating Fixed None All

Offshore

All

Onshore

Part Processing

Offshore

& Onshore

Dry

Trees

Dry

Trees

Wet

TreesMobile

Production

Unit

Jacket Full

Processing

Offshore

Wellstream

Transfer

to Shore

Korean

Grid

Power

Plant

Domestic

Users

Components

Strategies

Facilities

Elements

Gas Sales

Location

Semi-

Submersible

FPSO Jack-Up

The 3rd Workshop of the Cambodia PPM Case StudyKorea Institute of Geoscience

and Mineral Resources

DEVELOPMENT OPTIONS

Level 1:

Level 2:

Level 3:

TechnicalScreening

EconomicScreening

24 Options

8 Options

Selection

Separator, Compression, Dehydration,

Dewpointing, Condensate stabilization

Optimized Production

Process Selection

Position Selection

of Each Equipment

Brainstorm

Exercise

The 3rd Workshop of the Cambodia PPM Case StudyKorea Institute of Geoscience

and Mineral Resources

DEVELOPMENT OPTIONS

BULK WATER

SEPARATION

OFFSHORE FACILITIES ONSHORE FACILITIESPIPELINE

GAS

COMPRESSION

GAS

DEHYDRATION

LIQUID

DEHYDRATION

SLUG

CATCHER

GAS

DEWPOINTING

CONDENSATE

STABILIZATIONWATER

The 3rd Workshop of the Cambodia PPM Case StudyKorea Institute of Geoscience

and Mineral Resources

COMPOSITIONAL SIMULATION

•Phase IEstimation of the gas and condensate reserves

(GIIP) of Donghae-1 Gas Field

•Phase II

To evaluate the field’s development including

optimal well locations, various sensitivities and

water coning & partially penetrating wells

The 3rd Workshop of the Cambodia PPM Case StudyKorea Institute of Geoscience

and Mineral Resources

COMPOSITIONAL SIMULATION

EOS Modeling • 11 Components (CO2, N2, C1~C6, C7+)

• 5 Pseudo-Components

(Non-HC, C1, C2/C3, C4/C5, C6+)

Dew-point Phase Diagram Gas Water Pc Gas Water kr (Corey Eq.)

Capillary P (Pc) : SCAL Relative Permeability

The 3rd Workshop of the Cambodia PPM Case StudyKorea Institute of Geoscience

and Mineral Resources

COMPOSITIONAL SIMULATION

C1: Structure/Isopach/Grid B1 Reservoir B2 Reservoir B3/4 Reservoir

Grid : 47x43x15

Layers : C1, B1, B2, B3/4

Constant Thickness

The 3rd Workshop of the Cambodia PPM Case StudyKorea Institute of Geoscience

and Mineral Resources

Gas & Condensate

Production vs. TimeGas & Condensate Rate vs.

Cumulative Gas ProductionCondensate Yield, Water Cut

& Average Reservoir Pressure

COMPOSITIONAL SIMULATION

Base Case Results

• Ultimate Gas Recovery : 142 Bcf (68% of GIIP)

• Period of Production Plateau : 6 years

• Condensate Recovered : 1.2 MMbbl (37% of In-Place)

• Water Production Less Than 1.7 bbl/MMscf

The 3rd Workshop of the Cambodia PPM Case StudyKorea Institute of Geoscience

and Mineral Resources

COMPOSITIONAL SIMULATION

•PermeabilityProduction Performance vs. Horizontal Permeability

•Gas Initially In-PlaceProduction Performance vs. GIIP

•Surface Operating PressureProduction Performance vs. FWHP

•Plateau Production RateProduction Performance vs. Field Rate

•Strength of AquiferAquifer Strength Sensitivity

Effect of Aquifer Strength & Rate on Recovery

• Effect of kv and Selective Well Completion

The 3rd Workshop of the Cambodia PPM Case StudyKorea Institute of Geoscience

and Mineral Resources

COMPOSITIONAL SIMULATION

•Probable Reserve of Donghae-1 (Gorae V & V-3 Field) :208 Bcf of Gas, 1.77 MMbbl of Condensate

Minimum FWHP of 700 psi & Minimum Allowable Gas Well Rate of 5 MMscf/day Assumed

•4 Wells Required in the 4 Zones :•Retrograde Condensation :

2.5 MMbbl of condensate to remain in the reservoir in a liquid

state at the end of primary depletion.

1% of HCPV, immobile and no effect on gas deliverability

•Due to the modest k, the Aquifer Strength WeakInsensitive to Plateau Rate, GIIP

•Relatively high kv/khNo Effect on the Ultimate Gas Recovery, regardless of

penetration

The 3rd Workshop of the Cambodia PPM Case StudyKorea Institute of Geoscience

and Mineral Resources

Export Pipeline

Onshore

Infield Pipeline

Offshore

Donghae-1

Offshore Platform

Subsea

X-Mas Tree

Underground

Subsea

Onshore Terminal

Umbilical Line

B1

B2

P=3580 psia

T=218 oF

B3/4

P=3634 psia

T=219 oF

P2 P1 P3

TVD=7935 ft

MD=9125 ft

TVD=7935 ft

MD=8038 ft

TVD=7860.9 ft

Tubing ID=4.892”

Tubing WT=0.304”

7890.4 ft (2405 m)

8123.4 ft (2476 m)

7831.4 ft (2387 m)

PRODUCTION OPTIMIZATION

The 3rd Workshop of the Cambodia PPM Case StudyKorea Institute of Geoscience

and Mineral Resources

PRODUCTION OPTIMIZATION

Compositional Fluid Model

Gas-Condensate Flow

Peng-Robinson Cubic EOS (1976)

Flash Calculation

Gas (g) & Condensate (L) Fugacity fi

BZ

BZ

b

b

B

ABz

b

zb

pz

fk

k

iizk

i

i

k

i

414.0

414.2ln

2

82843.2)ln(

1ln

Subsurface Reservoir Model

Multi-Component Tank Model

Assumptions

Homogeneous, Isotropic, Cylindrical Reservoir

No-Flow Boundary Condition

No Water & Condensate Flow

Cumulative Gas Production

INTEGRATION

Multi-Phase Pipeline Flow Model

Vertical Pipeline (Production Well) – PIPESIM

Horizontal Pipeline – Multiphase Flow Model

Vertical & Horizontal Flow Patterns

Pipeline Network Model

PIPESIM (Build 26, 1999)

Transport Pipeline, Production Line, Riser

Branch System

Modeling of Separator, Pump, Compressor

P2 WellP1 Well

P3 Well

Topside Manifold

Separator

The 3rd Workshop of the Cambodia PPM Case StudyKorea Institute of Geoscience

and Mineral Resources

0 1000 2000 3000 4000 5000 6000

Time (Day)

0

10

20

30

40

50

60

Gas F

low

rate

(MM

SC

FD

)

P1P2P3Topside

Allocation

of Gas Production

Pressure Profile

at Separator

Cum. Gas Production

at Separator

Cum. Condensate

Pro. at Separator

0 1000 2000 3000 4000 5000 6000

Time (Day)

0

1000

2000

3000

4000

Pre

ssu

re (

psia

)

1610

Compression

P1P2P3Topside

0 1000 2000 3000 4000 5000 6000

Time (Day)

0

50000

100000

150000

200000

250000

Cu

mu

lati

ve

Gas (

MM

SC

F)

P1P2P3Topside

0 1000 2000 3000 4000 5000 6000

Time (Day)

0

1

2

3

Cu

m. C

on

den

sate

Pro

. (M

MS

TB

)

P1P2P3Topside

PRODUCTION OPTIMIZATION

Production Scenario

Total Production Rate: 50 MMscf/D

BD12, BD13 Line: Detour Line for Emergency

Platform Minimum Pressure: 500 psia

Allocation of Optimized Gas Production Rate

Optimized Production Rate

Plateau Period: 3900 Days

Compressor Installation: 2000 Days (5.5 yrs)

Cumulative Gas Production (During Plateau Period)

Cum. Condensate Pro. (During Plateau Period)

The 3rd Workshop of the Cambodia PPM Case StudyKorea Institute of Geoscience

and Mineral Resources

PRODUCTION FACILITIES

Subsea Production Facilities

Offshore Production Facilities

Onshore Structures

Pipeline

The 3rd Workshop of the Cambodia PPM Case StudyKorea Institute of Geoscience

and Mineral Resources

CONCLUDING REMARKS

• Donghae-1 Gas Field, Offshore KoreaProduction Options

DST

Reservoir Simulation

Integrated Network Modeling

Facility Design

• We are willing to actively involve in PPM Case Studies: collaborative work with Host Countries

Gas & Condensate Production (2004)

The End

Thank You.