8th European Conference on Gas Well De-liquification ,Groningen, 2013

DELIQUIFICATION & REVIVALOF OIL AND GAS WELLS

USING SURFACE JET PUMPSRecent applications and experienceRecent applications and experience

By: Sacha Sarshar ,Caltec

EFFECT OF FIELD DEPLETION ON WELL BORE PRESSURE & PRODUCTIONPRODUCTION

Inflow Parameters will change as the field depletesInflow Parameters will change as the field depletes and the shape of the inflow performance curve will change, potentially due to factors like:g p yChanges in relative permeabilities over timeIncrease in water productionReservoir compaction Closure of natural fracture

Near wellbore damageProduction below saturation pressures

Gas is released from oil resulting an increase of GOR Gas is released from oil resulting an increase of GOR Condensate is dropping in the reservoir resulting a decrease of

LGR – condensate banking.

Slide 2

MAIN CAUSES OF LIQUID BUILD UP IN WELLS• Low velocity of gas• Low velocity of gas• High FWHP, dictated by downstream process system

M ltiphase flo thro gh ell bore leads to flo regimes• Multiphase flow through well bore , leads to flow regimes such as Churn flow, slugging etc,which affect both the hydrostatic head and frictional losseshydrostatic head and frictional losses

• Effect of viscosity & density of liquids and gas• Inclined & horizontal profile of wells contribute to G-LInclined & horizontal profile of wells contribute to G L

separation within the well bore and generation of slugs; • liquid build up in pipelines could also aggravate theliquid build up in pipelines could also aggravate the

problem ,increasing FWHP• The flowing bottom hole pressure(FBHP) is the main factor g p ( )

affecting production, but FWHP is also a useful guide

Slide 3

COMPARISON OF FLOW REGIMES IN

Intermittent

Dispersed Bubble

iqui

d m

/s)

FLOW REGIMES IN HORIZONTAL AND VERTICAL PIPES

Annular Mist

erfic

ial L

iel

ocity

(mWavy

Stratified

Sup Ve

Flow regime in horizontal pipelines

Superficial Gas Velocity (m/s)

Slug

Annular Mistl Liq

uid

(m/s

)

Flow regime in vertical pipesAnnular MistBubble

uper

ficia

lVe

loci

ty g p p

FrothSu

V ≥ 5 m/s

Slide 4

COMMON REMEDIAL SOLUTIONS TO WELL DE-IQUIFICATION

• Regular gas blow down to atmosphere• Lower flowing wellhead pressure ( use of jet pump• Lower flowing wellhead pressure ( use of jet pump

technology or other methods)• Well shut-in IntermittentlyWell shut-in Intermittently• Use of foaming agents/intermittent or continuous• Tubing size modification/velocity string• Tubing size modification/velocity string• Artificial lift systems (Downhole) including downhole jet

pumps,ESPs, plunger lift,etc.pumps,ESPs, plunger lift,etc.• Best solution is dictated by well status,resevoir

characteristics, available source of energy, platform , gy, pconstraints and economic consideration

Slide 5

SELECTION PROCESS FOR WELL DELIQUIFICATIONBASED ON SEVERITY OF THE CASE

Case1(Mild) Case 2 (Medium) Case 3 (Sever)

Lowering the FWHP by SJP is sufficient

Well loaded, initial

offloading is needed

Downhole system needed

sufficient

SJP could enhance downhole systemsperformance

Lower FWHP by SJP

Aft i iti l ffl di

Use SJP plus intermittent

performance

After initial offloading offloading

Slide 6

Surface Jet Pump TechnologyPatented Universal Design Ejector / Jet PumpPatented Universal Design Ejector / Jet Pump

Some possible HP sources-;

Removable Nozzle

Removable Mixing tube /Diffuser

Some possible HP sources-;

- HP WELLS (oil or gas wells) - COMPRESSOR RECYCLED GAS

HP GAS FROM PROCESS SYSTEM A SINGLE PHASE (LIQUID) PUMP- HP GAS FROM PROCESS SYSTEM - A SINGLE PHASE (LIQUID) PUMP

- HP LIQUID(OIL,WATER)

Slide 7

Jet Pump Flow Dynamics

HPDischarge

Nozzle Mixing tube Diffuser

1 3 4 5 6 72 8LP

HP Flow

LP Flow

Combined Flow

ocity

Velo

sure

Pres

s

dP

8

MAIN FACTORS AFFECTING THE PERFORMANCE~ HP/LP PRESSURE RATIO~ HP/LP FLOW RATIO

~ GAS/LIQUID RATIO(LP FLOW)(oil or gas production cases)

Secondary factors;

- Mol. weight

- Temperature

- Liquid in gas- Liquid in gas phase

Slide 9

TYPES AND RANGES OF SJP APPLICATIONS

• Revival of dead wells (oil&gas wells)/ de-liquificationBoost production from oil or gas wells• Boost production from oil or gas wells

• Boost pressure of LP gas in a process system• De-bottleneck compressors• Eliminate intermediate compressorsp• Prevent HP wells impose back pressure on LP wells• Prevent flaring LP gas• Prevent flaring LP gas• Lower back pressure on pipelines/reduce liquid l di f i liloading of pipelines

Slide 10

SOME FIELD EXAMPLES

Slide 11

WELL REVIVAL –SPILAMBERTO FIELD,ITALY

Source of HP flow; HP gas wellSource of HP flow; HP gas wellBenefits;Gain in gas production by 23,000 g p y ,sm3/d (0.812MMscfd)For almost two years

Slide 12

BP Inde, UKCSSolution ; Used HP recycled gas to power ; y g pSJP, to draw-in low pressure satellite Shell wells

Benefits

Used 68 MMscfd of gas from LP Shell Used 68 MMscfd of gas from LP Shell wells into the exiting facilities.

Production increased by 25% Davy Line

Compressor Production increased by 25%

Increased intake capacity of compressor

Jet Pump

ExportDavy Line

Bessemer

Separator

p

De- bottlenecked exiting compressor Low Pressure Gas Wells

Dp

Removed liquids from LP wells and the pipeline Kilo

Juliet

Subsea LineAward winning solutiong

Slide 13

Groet field surface jet pump

Caltec

HP WellDryingunit

Jet Pump

15 km Pipeline

Compressor

LP Well

A dAt eductor:Pressure ratio HP/LP = 5Flow ratio HP/LP = 3

Gas liquid ratio (m3 liquid per 1 million m3 gas)HP well ;65LP well; 30

Slide 14

Bergen Drying Facility surface jet pump

Dryingunit

CaltecJet Pump

HP Well15 km Pipeline

Compressor

LP Well

p

C 1 At SJPCase 1 At SJPPressure ratio HP/LP = 4Flow ratio HP/LP = 2.3

Slide 15

Slide 16

Production optimisation by surface jet pumpK5ENC_QV101T.PV

kNm 3/dK5ENC_TT_101_T

°CK5ENC_PT_101_T

K5ENC T = well 1 26/05/2008 09:49:03.893

250 100 5 0 50 50 50 100

24.18

58.78

197.11

142.3950.8625.818.261.442.7594.99

After ten moths maximum stable flow reached using SJP

BarK5ENC_PT_103_T

BARK5ENC_PT_105_T

BARK5ENC_PT_107_T

BARK5ENC ROCV 101 T SP

200

11.87

4.54

10.11

K5ENC_ROCV_101_T_SP

%

150

0.00

100

50

Re-start of the well after a closed-in period of two

F low wel l T Analog value Analog value Ana log valu e Analog value Analog value Return s et pointd ays-336 -308 -280 -252 -224 -196 -168 -140 -11 2 -84 -56 -28

0 0 0 0 0 0 014/01 /20 08 1 6:4 7:42.74 54 6

closed in period of two years , with reduced FTHP from 40 to 26 bar using SJP

17

Chevron, USA (GOM)Solution ; HP gas from the existing compressor on recycle used to power the jet pump

BenefitsL d i l t th l tf b 200 i Lowered arrival p at the platform by 200 psi

Increased gas velocity and improved flow regime in wellsin wells

• Removed bulk of liquids in the pipeline, causing a further 140psi drop at the wellhead

(340 psi total pressure drop).

• Production increased by 24%.

Export40MMSCFD400 psig

200 psig

1250 i

Salesprocessy %

• 2.5 Bscf of otherwise lost reserves recovered.

Fl d li d t hi h t

Ejector 1250 psig

Recycle gas

•Flow delivered at higher pressure to compressor suction increased compressor throughput.

7.4 MMSCFD850 psig Subsea

manifold

GEMINI

(Php/Plp=4.9.Qhp/Qlp= 2.11,Pd/Plp=2 ) 27 miles

Slide 18

Alaska, USASolution ; Used HP gas from long string to offSolution ; Used HP gas from long-string to off-load the well via surface jet pump

Benefits;

• Used available wasted energy to off-load the well. Gas Jet Pump

• Total production from well raised to 7 MMscfd from 2.5 MMscfd. Production

LP Wet gasHP Gas

increased by 180%.

• Liquid loading cycle was reduced, hence Dual Completion

more sustainable production gain. Well

WELLCOM APPLICATION: Cendor, Malaysia

WELLCOM BOOSTING SYSTEM

Wellcom oil system ; multiphase HP wells were used to bring in closed low pressure oil wells.

I-SEP

Benefits

Used available energy from HP well

TO PROCESS SYSTEM

JET PUMPFROM HP WELL

GAS• Used available energy from HP well

• 20% pressure boost for LP wells. FTHP 360 psia

I-SEPSYSTEM

COMMINGLER

LIQUID• Increased production by over 35%

( 150 b/d ) FTHP 69.6 PSIA87 psia

3612 b/d

Dp FWHP; 17 4 psi

FROM LP WELL• Improved flow regime in well bore, stabilising production.

450 b/d+0.138 MMSCFD

Dp FWHP; 17.4 psi

Slide 20

Record of flowing bottomhole pressure before and after installing the jet pump system

Dp at wellhead=17 4 psi

1150

1200

Flowing bottomhole pressure (FBHP) Dp at wellhead=17.4 psi

1000

1050

1100

1150

850

900

950

1000

FBHP Dp =140 psi

700

750

800

06:0

0:00

06:5

7:00

07:5

4:00

08:5

1:00

09:4

8:00

10:4

5:00

11:4

2:00

12:3

9:00

13:3

6:00

14:3

3:00

15:3

0:00

16:2

7:00

17:2

4:01

18:2

1:02

19:1

8:02

20:1

5:02

21:1

2:02

22:0

9:02

23:0

6:02

00:2

1:00

01:1

8:01

02:1

5:01

03:1

2:01

04:0

9:01

05:0

6:01

06:0

3:01

07:0

1:54

07:5

9:32

Slide 21

SIZE MATTERS !

HI-SEPI-SEP

I-SEP

Slide 22

EFFECT OF SJP COMBINED WITH GAS LIFTINCREASED PRODUCTIONINCREASED PRODUCTION

Gaslift injectionWellhead

SJP

HPGaslift injection

system

Wellcom system &

Well production

Surface

w ra

te Additional

production

To downstream process

Production

via TubingGaslift injection

d O

il Fl

ow

Well

Prod

uce

Gaslift Injection Flowrate

Gaslift injection

Lift gas Gaslift Injection Flowrate

Pay zone Pay zone

Wellbore

Slide 23

Wellbore

ANGSI FIELD,MALAYSIA,

REVIVAL OF 16 LP GAS WELLS

Slide 24

ANGSI FIELD,MALAYSIA

ANGSI FIELD,USE OF TEST SEPARATOR TO MEASURE FLOW RATE OF GAS AND LIQUIDS AT LOWER FWHPS

- -

WELL REVIVAL AND FLOW RATE MEASUREMENTUSING

THE TEST SEPARATOR

Well Revival

THE TEST SEPARATORAPPLIES TO BOTH GAS AND OIL WELLS

Well Revival Gas Jet Pump

Well Revival

HP Gas

To vent or Well Revival

Liquid Jet PUMP

HP Liquid

To vent or flare ,option3)

(Option 2)

LP Wells

Test Header

M

Gas

Closed drain

Production Header

Test SeparatorM Liquid

Closed drain

(option 1)

c.

10 October, 2013Presentation title 27

To Pressure Relief Line

Gas Jet PumpDischarge Silencer

Production Cooler 14” Sub Sea

PTPT

TTPT PT

Silen

cers

Sk

id

HP Well

CoolerLine to CPP

LP Silencer

Di h

Jet Pump Skid

PTAlternative

use of booster pump

PT

Well Revival Jet Pump

PT

Discharge Silencer

cers

d

Test Header Commingler

TTPT

LP SilencerJet Pump Skid

Silen

cSk

i

Test Separator

MLP Wells

Test Cooler

gLP Silencer

M

MProduction Header

USE OF TEST SEPARATOR TO REVIVE LOADED WELLSUSE OF TEST SEPARATOR TO REVIVE LOADED WELLS

Slide 28

TYPICAL NOZZLE PERFORMANCE CURVE

10 October, 2013

Well performance curve

Original tangent line for PI at DD1

DD1

wn Pressure

Well performance curveIn different years

Jet pump performance

Operating point

Dra

wdo

w

DD2

(Psi

)

N

Operating point

IPRIPR

New tangent line for PI

duct

ion

ssur

e

Production increase

Production rateProd

pres

CHANGES TO PI AT DIFFERENT FWHPs

HOW THE PERFORMANCE OF THE WELL AND THE SJP MATCH

KEY; DD1 & DD2; DRAWDOWN 1&2

ECONOMICS; USE OF SURFACE JET PUMPS• Low capital costCapital recovery within a few weeks to a few months• Capital recovery within a few weeks to a few months

• Short delivery period ; 8 to 14 weeks• Practically no operation cost /passive operation• Practically no maintenance costPractically no maintenance cost• Alternative solutions more complex and costlierR t l ti il bl t i i i it l t• Rental option available to minimise capital cost

• Short life period is economically acceptable• Could enhance what is achieved by other deliquification systems q y

Slide 31

CLOSING REMARKS• Simplicity & cost effectiveness makes surface jet pump

solutions very attractive & economicaly• A good tool for initial well deliquification before the situation

worsens• In addition to economic benefits, eliminating intermediate

compressors, deferring compressor upgrading or reducing li id h ld i i li ddi i l b filiquid hold up in pipelines are additional benefits

• The system can work well with other deliquification l tisolutions

• Installing tie-in points during shut downs simplifies installationinstallation

• Rental option justifies very short operation life

Slide 32

THANK YOUTHANK YOUQUESTIONS WELLCOMEQUESTIONS WELLCOME

Slide 33