OLGA Online Virtual Flow Meter - Aker Solutions

Practical Experience of Virtual Flow Meter
Solutions
FA and Dynamic Simulation Seminar, 23.10.2012
Jon R. Heum, e-Field Manager Europe
1

Client Metering Challenges
• Wells and pipeline systems have
been put subsea.
• Compression and separation
units are now being introduced
subsea
• IOC’s are planning to put oil and
gas «factories» subsea within
this decade
• Introduces challenges to well
and process metering and
performance monitoring
3

For typical large,
complex subsea
fields operated by
IOCs
For mature fields
For smaller subsea
developments
operated by a NOC
or similar
Client Metering Challenges
• Need a backup solution for physical Multiphase Flow
Meters
• VFM on each wellhead for systems with only one
MPFM installled per manifold
• MPFM retrofit can be a very high cost solution for
well performance montitoring (show stopper).
• VFM is an attractive solution in marginal fields with
limited profitability
4

Architecture – From OLGA Online PMS to VMS
Real Time
Monitoring
(RTM)
Graphical User Interface
(Web portal)
Advisory Functions
(Advisors)
Look Ahead Offline
Prediction Virtual Metering Analysis Module
(LAM) (WIM)
Databases and Interfaces to Control
System/PI
5

OLGA VFM – Value of being powered by OLGA
Combines a VFM calculation and visualization module with
the OLGA simulation engine.
The OLGA VFM calculates multiphase flowrates at various
locations throughout the entire production system (e.g. wells,
manifolds, flow lines, risers, inlet processing).
The OLGA VFM utilize online dynamic
models, which give realistic flow
calculations even during transient
operations.
6

VMS – Add on to Existing OLGA Online Solution
Real Time
Monitoring
(RTM)
Graphical User Interface
(Web portal)
Advisory Functions
(Advisors)
Look Ahead
Prediction
(LAM)
Offline
Analysis
(WIM)
Databases and Interfaces to External
Systems
Virtual Metering
Module
7

Deepwater Oil Field
Online Flow Assurance System
Client/Operator: Confidential
Site: West Africa
Delivery: 2012
System Integration:
• OSI PI Historian
Model (OLGA):
• Production wells
• Flowline loops
• Tiebacks and risers
• Separators
• Gas injection
• Fluid displacement
Modes:
• Real-time
• Look-ahead
• Planning (what-if)
Applications:
• Transparent production
system
• Pig tracking and fluid
displacement advisor
• Slug and surge volume
advisor
• Hydrate advisor
• VFM
• Cool-Down advisor
• Advanced Well restart
advisor
8

Goliat
Online Flow Assurance System
Client: ABB
Operator: ENI
Site: Norway
Delivery: 2014
System Integration:
• ABB process control
• Aker subsea control
Model (OLGA):
• 11 subsea production wells
• Production and injection
system
• Topside separators
OLGA Online FAS:
• Virtual Flow Metering
• Liquid Inventory
• Slug Monitoring
• MEG Monitoring
• Hydrate Monitoring
• Pig Tracking
• Wax Warning
• Production Forecast
• Well Start-Up Advisor
• Ramp-up Advisor
• Subsea Production System
Training Simulator (What-If)
ABB FAS Applications:
• Active Flowline Control
• Automatic Deduction Testing of
Wells
• Common User Interface
9

Gas Field Virtual Flow Metering System
Client/Operator: Confidential
Site: South China Sea
Delivery: 2012
System Integration:
• Emerson DeltaV process
control system
• Aker Solutions subsea
control system
Models (OLGA):
• 3 production wells
• Production chokes
• 22.5 km subsea pipeline (8”)
• Inlet separator at YC 13-1
platform
• Well (down hole) to
Downstream Choke
• Well (down hole) to
Upstream Choke
• Upstream Choke to
Downstream Choke
Real-time Application:
• Virtual flow metering
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How does it work?
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• P1 - Reservoir Pressure
• P2 - Downhole Gauge
• P3 - Downhole Gauge 2
• P4 - Upstream Choke
• P5 - Downstream Choke
Well Data Points
Q’ 1 = Q 1 *(ΔP’ 12/ΔP 12)
Q’ 2 = Q 2 *(ΔP’ 24/ΔP 24)
Q’ 3 = Q 3 *(ΔP’ 34/ΔP 34)
Q’ 4 = Q 4 *(ΔP’ 45/ΔP 45) 0.5
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VFM functionalities
• Weighting the different flow rate calculations into an overall flow rate
calculation (f. ex. for known bad measurements/meters)
Q VFM =
4
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i�1
• Benchmarking model to well test data
• Calibrating the model for optimum fit (GOR, WC, IPR coefficients, P res, T res,
Roughness, Fluid properties, Choke Cv and Heat Flux)
• Adjustments for meter/model uncertainty
• Input Data validation
η
Q
• Instrument redundancy
i
i
'
• VFM health logic (including warning and alarms for large deviations between
OLGA and measured values)
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Summary
• There is a continuous need for flow measurements in a range of different
type of oil and gas fields.
• Virtual Flow Meters could in some instances replace expensive Multi Phase
Flow Meters, or could be used as redundant measurements together with
MPFMs.
• Virtual Flow Meters has proven to provide accurate results.
• The versatility and accuracy of the OLGA simulator ensures reliable and
stable measurements for both steady state and transient scenarios.
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Thank you!
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