Transcript PI for Decision Support in Offshore Production Environments Rex L. Spahn

PI for Decision Support in Offshore
Production Environments
A Review of BP’s Troika Field
Rex L. Spahn
Manatee, Inc.
Troika Production System
Control System Primary Functions
• Operate hydraulically-actuated valves
• Take corrective actions during shut-ins
caused by abnormal conditions
• Provide chemical injection
• Provide data from downhole and tree
instrumentation
Control System Layout
HPU MCS
HUTA EUTA
EFL
SCP XMAS
TREE
HFL
Electrical
Hydralic/Chemical
CIU
UPS
ETU
ETU
HDM A
Manifold
Area 1
HDM B
Control System Architecture
ESD
Watchdog
PLC A
Operation
MCS A
Control
Station Computer
Watchdog
PLC B
MCS B
Computer
Ethernet
Printer
HPU
UPS
On-Line
Selector
SMU A
SMU B
Sub-Sea Systems
SESD
Houston
Monitoring
Station
Troika Data Acquisition System
What is it?
• Primarily an Operational and
Surveillance Database
• Production optimization (drawdown)
• History of operations
• Graphical and numerical record of data
Troika Data Acquisition System
What is being monitored?
• Wells
– Downhole pressure / temperature (3)
– Wellhead pressure / temperature (2)
– Flow rates calculated from downhole
pressure/temperature (oil, gas, water)
– Casing pressure (1)
– Choke position (1)
• Bullwinkle Production Platform
– Separator pressures / temperatures (5)
– Separator rates (oil, gas, water) (7)
PI Implementation
• Installed in fall of 1997
– PI server located in BP’s offices
• Batch process initially
– data files created daily by MCS and weekly
by Bullwinkle personnel
– data files converted and processed by PI
batch file processor
• Real-time system since mid-1998
– upgraded communication link
– daily files still created for backup
– Bullwinkle data still batch process
PI-ProcessBook for Troika
MCS Well Mimic
PI-ProcessBook Well Mimic
TA-3 Oil Flowrate
35000
TA-3 Csg. Pressure
1800
25000
20000
1000
15000
10000
500
0
0
3/18/98
3/20/98
3/22/98
TA-3 Wellhead Press.
11000
3/18/98
3/20/98
3/22/98
TA-3 Wellhead Temps
180
8000
100
6000
50
4000
1000
3/18/98
3/20/98
3/22/98
-10
3/18/98
3/20/98
TA-3 Downhole Press.
12000
TA-3 Downhole Temps
180
8000
175
6000
170
4000
2000
-2000
3/18/98
3/22/98
165
3/20/98
3/22/98
160
3/18/98
3/20/98
3/22/98
MCS Summary Screen
PI-ProcessBook Summary Screen
BOPD
BWPD
MMSCFD
TA-1
3,598
-1
TA-2
0
TA-3
Production vs. Test
Choke
BHP
UP
DP
6.9
18.1
9,902
6,606
2,778
-1
0.0
-0.7
10,064
6,770
519
-1
1.1
-1.2
10,049
TA-4
1
0
0.0
0.0
0
TA-5
30,054
-763
58.9
-4.4
TA-6
1
0
0.0
0.0
Casing Pressure
BHT
UT
DT
1,036
174
136
144
2,606
380
170
43
43
1,552
27
170
44
43
0
0
0
32
0
0
9,984
4,144
2,614
1,220
184
168
168
0
0
0
0
32
0
0
Uses of Downhole Pressure Gauges
• Well management (maintain desired
drawdown)
• Reservoir characterization (static and
dynamic)
– Rate & pressure simulation history match
– Frequent PBUs without loss of production
– Multi-rate analysis during well start-ups
• Redundancy (via nodal analysis)
• Well ramp-up and downtime history
Downhole Pressure Gauge Trends
Bottomhole Pressures (psia)
11000
11/5/98 03:20:03 PM
10500
10000
9500
9000
8500
10/24/98 10/25/98 10/26/98 10/27/98 10/28/98 10/29/98 10/30/98 10/31/98 11/1/98 11/2/98 11/3/98 11/4/98 11/5/98
Downhole Pressure (P3)
Downhole Pressure (P3)
Downhole Pressure (P3)
Downhole Pressure (P3)
Downhole Pressure (P3)
Downhole Pressure (P3)
W01-DFM-P3
8968.91895
psia
W02-DFM-P3
8869.66602
psia
W03-DFM-P3
9862.42773
psia
W04-DFM-P3
0.00000
psia
W05-DFM-P3
9950.60742
psia
W06-DFM-P3
0.00000
psia
Uses of Downhole Flowmeters
• Oil, gas and water rates calculated
• Accuracy - typically +/- 5% compared to
Bullwinkle metered volumes
• Production rates used for daily
production allocation to wells
• Primary well test method
• Redundancy (via nodal analysis)
• Downtime
Downhole Flowmeters
Oil Flowrates (bbl/day)
35000
10/21/98 08:50:52 AM
30000
25000
20000
15000
10000
5000
0
10/8/98 10/9/98 10/10/9810/11/9810/12/9810/13/9810/14/9810/15/9810/16/9810/17/9810/18/9810/19/9810/20/98
DFM Oil Rate
DFM Oil Rate
DFM Oil Rate
DFM Oil Rate
DFM Oil Rate
W01-DFM-FQIO
8360.05176
bopd
W03-DFM-FQIO
26400.46680
bopd
W04-DFM-FQIO
1.00000
bopd
W05-DFM-FQIO
6744.41504
bopd
W06-DFM-FQIO
1.00000
bopd
TA-2 FLOWRATE.Allocated Oil
18669
Annulus Pressure Monitoring
• As production begins, annulus heats up
and fluids expand
• Pressure in annulus continuously
monitored and bled off at 3000 psia
Casing Pressure
11/4/98 07:58:38 AM
W01-AP
2785.68872
W02-AP
1824.93408
W03-AP
388.73508
W04-AP
0.00000
W05-AP
1341.63220
W06-AP
0.00000
3500
3000
2500
2000
1500
1000
500
0
10/29/98
10/30/98
10/31/98
11/1/98
11/2/98
11/3/98
11/4/98
Flowline Monitoring
• Easy access to historical data
• Flowline thermal data
– wellhead temperatures (inlet)
– fluid temperatures at Bullwinkle (outlet)
– production rates
• Flowline model used to:
– monitor flowline performance
– predict performance at other rates
– determine pigging schedule for paraffin
removal
Flowline Temperature Data
Flowline Temperatures (In/Out)
180
11/12/98 01:05:05 PM
BUSOIZ1:CAO1-TIT-1011.F_CV (S)
87.30000
BUSOIZ1:CAO1-TIT-1012.F_CV (S)
84.30000
160
W01-DT
155.62354
Deg. F
W02-DT
158.54231
Deg. F
W03-DT
42.22077
Deg. F
W04-DT
0.00000
Deg. F
W05-DT
170.66959
Deg. F
140
120
100
80
60
40
11/6/98
11/7/98
Flowline 1011 Inlet Temp
Flowline 1012 Inlet Temp
Downstream Temp
Downstream Temp
Downstream Temp
Downstream Temp
Downstream Temp
11/8/98
11/9/98
11/10/98
11/11/98
11/12/98
Preventive Maintenance Planning
• Maintenance critical on subsea system
due to high cost of repairs
• Preventive Maintenance (PM) program
key to achieving desired operating
expenses
• Data important to PM program:
– valve operating cycles
– hydraulic pressures
– valve positions
Preventive Maintenance Data
Key Benefits of PI
• Ability to place key information on right
person’s desk
– lower cost per desktop than control system
• Critical data stored within PI
• With RAS connection, real-time and
historical data can be accessed from
most anywhere
Other Benefits
• Historical data easy to access and trend
• Real-time and historical analysis of data
performed using Excel™-based
Datalink
• Well downtime calculated consistently
• Unusual events can be reviewed by
experts to aid in diagnosis
Future Considerations
• Include PI in planning overall data
management strategy
• Use PI-ProcessBook as primary data
interface within control system
– use control system to issue commands and
react to abnormal conditions
– leave the data to PI
• Locate PI server offshore to ensure data
integrity
Conclusions
• Real time and historical data is valuable
– historical trends of reservoir characteristics
– monitor flowline & system performance
– diagnose problems
– improve overall production efficiency
• Significant production increase
attributed to data monitoring system
• PI being implemented at other BP
Amoco offshore production facilities
PI for Decision Support in Offshore
Production Environments
A Review of BP’s Troika Field
Rex L. Spahn
Manatee, Inc.