Salinity issues still impacting North Sea Saturn Banks gas flow
Sept. 30, 2022
Gas production from IOG’s Saturn Banks development in the UK southern North Sea continues to be constrained by intermittent flows of aqueous liquids into the reception facilities at the Bacton terminal.
Courtesy IOG
Offshore staff
LONDON — Gas production from IOG’s Saturn Banks development in the UK southern North Sea continues to be constrained by intermittent flows of aqueous liquids into the reception facilities at the Bacton terminal.
The aqueous liquids comprise saline water and monoethylene glycol (MEG), which is injected into the wells to inhibit hydrate formation.
When liquids arrivals reduce available storage capacity, the terminal control room cuts gas flow to avoid overfilling the Saturn Banks slug catcher and shutting in production. Then, as liquids are let down from the slug catcher and removed, gas flow rates can be gradually increased.
According to IOG, the current letdown capacity is restricted by storage availability (partly because this is shared with liquids from other fields). The company and terminal operator Perenco are working on modifications to enable continuous letdowns.
Analysis suggest a sub-seismic resolution natural reservoir fracture encountered during development drilling on the Blythe Field is the most likely source of the saline water. So IOG is assessing ways to optimize Blythe reservoir management.
Courtesy IOG
Over the next few weeks, it plans to steadily restore higher stabilized flow rates, subject to liquids handling constraints. As gas rates rise, the company will also evaluate the aqueous liquids production increase.
