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Use of subsea Multiphase pumps as an alternative
to ESP workover in a mature field developmentKia Katoozi
May 2016 1
Agenda
• The Otter Field
• ESP History
• Otter production & Injection scenarios
• MPP Feasibility study – Objectives
• Production profiles
• MPP Technical feasibility summary
• ESP v MPP in Otter
• Commercial assessment
• Recommendation
May 2016 2
The Otter Field
• Block 210/15a
• 93 miles NE of Shetland in 180meter water depth
• 1st Oil in 2002
• Subsea tie-back to Eider platformvia 21 km pipeline
• 3 ESP lifted production wells
• 2 water injection wells
• Expected field life 4 years!
• 6,000 bopd @ 77% watercut
May 2016 3
The Otter Field – Production & Injection (Current status)
May 2016 4
ESPs
OTTER
Otter Sep.
Pressure: 26bar
0
1
2
3
4
5
P1 P2 P3Ru
n L
ife
(yrs
)
Work over 2
Expected life Primary Back up
0
1
2
3
4
5
P1 P2 P3Ru
n L
ife
(yrs
)Work over 1
Expected life Primary Back up
ESP History
May 2016 5
Primary: Lower ESP
Back-up: Upper ESP
Assumption for the failure date of the current systems:
P1: 01/01/2018 for both systems; primary and back-up.
P2: 01/09/2016 for both systems; primary and back-up. The primary ESP
already has 81 number of starts.
0
1
2
3
4
5
P1 P2 P3Ru
n L
ife
(yrs
)
Original
Expected life Primary Back up
Otter Production & Water Injection
(NFI)
May 2016 66
ESPs
01
/01
/201
8
01
/09
/201
6
01/06/2017 01/06/2018
OTTER
Otter Production & Water Injection
(Base case)
May 2016 7
ESPs
01
/01
/201
8
01
/09
/201
6
WINJ
REPAIR
WINJ
REPAIR
OTTER
WINJ
REPAIR
WINJ
REPAIR
Otter Production & Water Injection
(Base case + ESP)
May 2016 8
ESP
replacement
OTTER
WINJ
REPAIR
WINJ
REPAIR
Otter Production & Water Injection
(Base case + MPP)
May 2016 9
MPP
01/06/2018
OTTER
To demonstrate that multiphase subsea pumping is a feasible technology for
the Otter field to boost production from all 3 wells. The key areas of focus
have been:
- System deliverability and flow assurance
- Pump suitability and expected time to failure
- Electrical power supply
- Subsea installation
- Controls, instrumentation and barrier fluid
- Commercial feasibility
MPP Feasibility study – Objectives
10May 2016
Production Profiles
May 2016 11
P2 ESP failure
P1/P3 Natural flow
P1 ESP failure P1 Natural flow with WI
MPP installation
Assumptions
• ESP failures:
• P1: 01/01/2018
• P2: 01/09/2016
• Separator P: 26bar
• Shaft power: 750kW
• Suction P: ~5bar
• Pump dp: 45bar
• MPP Option: 01/06/2018
• ESP Option:
• P1 w/o: 01/07/2018
• P3 w/o: 01/07/2017
P3 ESP w/o
P1 ESP w/oP3 ESP failure
Modelling shows that MPP can deliver at least 50% more than 2 x ESP workover, based on 5 barg suction, 45 bar head, 750kW power, 26 barg arrival pressure.
There is a type of helico-axial pump available that can perform the required service and has a MTTF of 5-6 years. (anticipated life is 3.5 years)
It is expected that a single VSD (Variable Speed Drive) could deliver 920 kW to a subsea booster pump. Modelling performed during feasibility is based on 750 kW. Pump power to be optimised in next phase of the project- consider risk/reward of pairing VSDs.
Pump can be integrated into existing facilities well and installation is relatively straightforward.
MPP Technical feasibility summary
12May 2016
ESP v MPP in Otter (Pros & Cons)
May 2016 13
ESP
Pros
- Proven technology
- Pumping from deeper depth (system can
be operated with a lower reservoir
pressure)
- There is a redundancy if a pump fails
Cons
- Workover is expensive and time
consuming
- Time to repair is long (rig requirement,
weather dependant)
MPP
Pros
- MPP boost the full field production
- MTTF 5 to 6 years and Repair cost is low
- Time to repair is short (vessel requirement, less weather dependant)
Cons
- Initial installation cost is high
- Need to flush & connect into flowline for installation
- Requires positive wellhead pressure
- Single point failure for the field
Power, cable, umbilical and barrier fluid are already in place for either system
Commercial Assessment
14May 2016
Decision to install
MPP generates
greater NPV, but
requires additional
risked CAPEX
WellESP Failure
Dates
ESP
repairs
MPP
InstallationNPV
PV
CAPEX
Branch
ProbablityEMV
`
OUP1 01/01/2018 No
OUP2 01/09/2016 No 01/07/2018 34.4 50.9 100% 34.4
OUP3 01/09/2013 No
OUP1 01/01/2017 01/07/2017
OUP2 01/09/2016 No No 10.3 49.0 20%
OUP3 01/09/2013 01/09/2017
OUP1 01/01/2018 01/07/2018
OUP2 01/09/2016 No No 21.6 48.1 35%
OUP3 01/09/2013 01/07/2017
OUP1 01/01/2019 01/07/2019
OUP2 01/09/2016 No No 27.2 46.8 20% 27.0
OUP3 01/09/2013 01/07/2017
OUP1 01/01/2019 01/09/2019
OUP2 01/09/2018 No No 41.9 44.0 20%
OUP3 01/09/2013 01/07/2019
OUP1 Never No
OUP2 Never No No 70.7 5.4 5%
OUP3 01/09/2013 01/07/2017
Production ProfilesB
ase
Cas
eB
ase
Fai
lure
Dat
es
Inst
all M
PP
Dec
isio
n
Earl
ier
fail
ure
of
P1
Co
nti
nu
e w
ith
ESP
Dec
isio
n
P1
late
r fa
ilu
re
dat
e
P1
& P
2 la
ter
fail
ure
dat
es
No
Fai
lure
of
ESP
s
0
1000
2000
3000
4000
5000
6000
7000
8000
9000
Po
ten
tial
oil
rate
Scenario 1a
0
1000
2000
3000
4000
5000
6000
7000
8000
9000
Po
ten
tial
oil
rate
Scenario 1b
0
1000
2000
3000
4000
5000
6000
7000
8000
9000
Po
ten
tial
oil
rate
Scenario 2
0
1000
2000
3000
4000
5000
6000
7000
8000
9000
Po
ten
tial
oil
rate
Scenario 3
0
1000
2000
3000
4000
5000
6000
7000
Po
ten
tial
oil
rate
Scenario 5
0
1000
2000
3000
4000
5000
6000
7000
8000
9000
Po
ten
tial
oil
rate
Scenario 6
Multiphase pump technology for Otter is feasible and allows Otter to
continue to produce beyond the failure of the existing ESPs.
Water injection availability is a pre-requisite to longer term production and /
or development of Otter / Eider.
MPP installation takes the uncertainty away and present reasonable NPV.
ESP work over may generate higher NPV but presents high level of
uncertainty. Need to have capability to react to ESP failures.
Recommendation
15May 2016