Laggan-Tormore: reservoir to sales production forecasting and optimization using an integrated modelling approach

Abstract

AbstractLaggan and Tormore are gas-condensate fields in the West of Shetland region of the UK, to be developed as a 143 km subsea tie-back (twin 18″ flowlines) to a new onshore gas plant (Shetland Gas Plant, SGP). Condensate will be sent to the neighbouring Sullom Voe Terminal for stabilization and a new 30″ gas export pipeline will provide a route from the SGP to Total's St Fergus terminal on the UK mainland. The development is planned as a hub to enable future development of similar reservoirs in the region.Production forecasting and field management are complex due to the evolving nature of the reservoir compositions over time, the back-pressure and flow assurance impacts of the long flowlines and final sales products being delivered at two remote terminals. This will be further complicated with the introduction of any additional fields, requiring an accurate understanding of field interactions, pipeline ullage, plateau extension and management of production allocation. To address these issues, Total E&P UK (TEPUK) have developed an integrated asset model (IAM) using state-of-the-art techniques to model the system from reservoir to final product sales. The IAM will be used to communicate a common geosciences and development understanding for forecasting and future development studies.