1. Distributed-parameter modelling in petroleum extraction Towards on-line applications David Cameron Fantoft Process Technologies

2. 2000-05-03© 2000 Fantoft Prosess as Disposition Corporate background. Distributed-parameter modelling. Single-phase and multiphase pipeline modelling. On-line applications of pipeline models. Technical challenges.

3. 2000-05-03© 2000 Fantoft Prosess as Fantoft Process Technologies www.fantoft.no Offices in Oslo, Southhampton, Houston and St John’s. Supplier of: Process studies. Simulator systems. Real-time systems.

4. 2000-05-03© 2000 Fantoft Prosess as Distributed-parameter modelling We’ve been doing it for years: Without knowing it? Standard models in dynamic simulators: Pipe. Heat exchanger. Separator. Discretisation has sometimes been a bit coarse! New challenges from process intensification and sub-sea operations.

5. 2000-05-03© 2000 Fantoft Prosess as Compact heat exchanger Example of a relevant unit operation for off-shore operations. Complicated flow geometries. Every case is different. Want to be able to build a geometry from elementary heat transfer ”lego blocks”.

6. 2000-05-03© 2000 Fantoft Prosess as Down-pipe separator. Existing technology: Big tanks, low-shear separation. Use a lumped model with three homogeneous lumps – gas, oil and water. New technology: High-shear separation. Need to model shear field to predictively model process.

7. 2000-05-03© 2000 Fantoft Prosess as Single-phase and multiphase pipeline modelling. Well-established off-line technology: OLGA is a well-known, widely used tool. D-PIPE: single-phase pipeline. Conservation of mass, momentum and energy Transient, one-dimensional form.

8. 2000-05-03© 2000 Fantoft Prosess as D-PIPE and D-SPICE D-SPICE Dynamic process simulator. D-PIPE Single-phase dynamic pipeline model within D-SPICE. D-SPICE is also interfaced with OLGA to provide multiphase capabilities.

9. 2000-05-03© 2000 Fantoft Prosess as D-PIPE

10. 2000-05-03© 2000 Fantoft Prosess as On-line applications of pipeline models Leak detection. Leak location. Look-ahead and planning. Instrument monitoring. Line-pack optimisation. Compressor optimisation. Batch and scraper tracking.

11. 2000-05-03© 2000 Fantoft Prosess as An on-line pipeline system System functionality: Leak Detection Leak Location Leak Size Calculation Hydrate Formation Detection Pig Tracking Batch Tracking Inventory Control (gas packing, liquid condensing) Model functionality: Real Time Calculation and Monitoring including data validation Fast look ahead Planning Optimisation Model tuning Model: Single phase pipelines: – liquid – gas Multi phase pipelines: – 2 phase – 3 phase Pipe network

12. 2000-05-03© 2000 Fantoft Prosess as Scraper tracking

13. 2000-05-03© 2000 Fantoft Prosess as Technical challenges (1) Computational burden. Real-time. Inner loop in optimisation. Stability within network solver. Hierarchical solution algorithms. Development effort. Generation of gradient information for solvers and optimisers.

14. 2000-05-03© 2000 Fantoft Prosess as Technical challenges (2) Statistical treatment of residuals: Differentiation of different types of error: Model error. Sensor error. Leakage. The key: spatial and time correlation of residuals.