|
|
|
| |
 |
| • |
Rapid evaluation of gas contract scenarios |
| • |
Links to complementary models for data sources |
| • |
Easy-to-use PC based |
| • |
Easy to maintain and modify in-line with contractual changes |
|
|
|
|
Challenge
The contracts associated with gas supply in the U.K. sector of the North Sea are both numerous and complex. The schedulers are responsible for administrating the gas operations on behalf of Shell Expro and the various partners associated with each platform/field in the sector. On a daily basis they must balance the gas landed at St. Fergus gas plant with a range of contractual constraints including quantity and quality of gas exported and the ethane supplied to the Fife NGL plant. For this purpose Shell Expro
sought a flexible and easy-to-use system to replace existing
programs which could no longer be updated to represent the current
situation.Solution
The system is designed to perform short to medium term planning of gas production from the Northern and Central North Sea fields, its treatment in the St. Fergus gas plant and the allocation of the final products back to the contributing fields.The NSPS system considers all the North Sea platforms which deliver their gas to shore through the FLAGS or Fulmar Gas Pipelines. It is designed to have the flexibility to handle new fields as well as major changes in operating circumstances.
A
major feature of the system is the technique for combining the contractual arrangements (each field nominates, uniquely, how it would like to operate the gas plants) with the capabilities of the plant itself which can only support a single set of conditions at any one time. NSPS is primarily used to interpret the requirements of the Gas Schedulers as a set of objectives and constraints for the St. Fergus and Mossmorran plants, and, in particular, for their on-line
optimizers. Direct interaction with the process itself is
intended to be minimal. However, key performance parameters employed in the NSPS will be provided by the on-line optimizers (either direct plant readings or model output data) and dynamic models developed for the FLAGS and FGL pipelines. The data will be continuously available enabling the NSPS to pick up the most recent values as and when required.
The system is used both by process engineers to evaluate different
operating scenarios and hydrocarbon accountants to acquire detailed oil
allocation information.
 Back
to Top |
