Following shutdown, North Sea gas project back online

UK-headquartered IOG plc has restored production from its Saturn Banks Project – Phase 1 in the UK sector of the North Sea, after a shut-in to enable the final subsea connection to Southwark.

The IOG-operated Saturn Banks Project – Phase 1, which was sanctioned in October 2019, consists of Blythe, Elgood, and Southwark fields in the UK Southern North Sea. The first two fields – Blythe and Elgood – were brought on stream in mid-March 2022. IOG holds a 50 per cent stake in this project and its partner CalEnergy Resources holds the remaining 50 per cent.

The normally unmanned Blythe platform, connected to Saturn Banks Pipeline System (SBPS) that feeds into the associated Saturn Banks Reception Facilities at the Bacton terminal, is used for Blythe and Elgood production.

IOG disclosed on 30 September 2022 that the Perenco Bacton terminal was scheduled to undergo annual maintenance in November during which Saturn Banks production was expected to be suspended for up to two weeks.

However, on 19 October 2022, the UK player changed the duration, explaining that the production from its Saturn Banks project would be shut-in for a total of four weeks to enable the final subsea connection to Southwark. This included depressurising the line ahead of the Bacton terminal shutdown.

The company further elaborated that Subsea 7’s DSV Seven Atlantic had been operating offshore to connect the outer section of the Saturn Banks Pipeline System from the 24″ manifold to the Southwark platform, to prepare for the introduction of gas from Southwark.

“Due to a defective 6″ offshore valve the SBPS will need to be depressurised in order to connect the outer section safely to the manifold. Saturn Banks production will therefore be suspended in late October for approximately four weeks, including the November Bacton terminal annual shutdown,” underscored IOG.

On 11 November 2022, the firm reported that the Saturn Banks Pipeline System was depressurised as planned to enable the safe installation of the final subsea spool connecting to Southwark.

IOG revealed that the production was expected to restart in late November, subject to operational risks and Perenco Bacton terminal maintenance, which started overnight on 4-5 November. In addition, dewatering and backgassing of the SBPS outer section to Southwark were planned to be completed during the shutdown.

In an update on Friday, the UK firm confirmed the production restart from both Blythe and Elgood fields into the Saturn Banks Pipeline System, after the completion of shutdown works. According to IOG, gas sales are expected to recommence on the same day, following the full repressurisation of the line.

Rupert Newall, CEO of IOG, commented: “I am very pleased to confirm that Saturn Banks Phase 1 production has been safely restarted after successful completion of shutdown activities. This was one of our top priorities as the new leadership team and the real commitment shown across the team to meet this key objective bodes well for our continuing work to address recent operational challenges.”

The company highlights that the final connection, dewatering and backgassing of the SBPS outer section to Southwark have all been completed, bringing it up to pressure ahead of the first gas. Moreover, additional modifications were also completed in parallel at Saturn Banks Reception Facilities onshore at the Bacton terminal to de-risk potential for future shutdowns.

In the past, IOG experienced several setbacks with its Southwark drilling campaign, which delayed its progress. These setbacks resulted in a two-month hiatus caused by an issue on one of the legs of the Noble Hans Deul jack-up rig.

In addition, subsequent technical issues with an underwater Remotely Operated Vehicle (ROV) further prolonged the company’s timeline. Back in January 2022, the challenges associated with seabed conditions threatened to compromise rig stability, thus, causing yet another delay for IOG.

However, with hydraulic stimulation underway at the A2 well, the company is focused on bringing Southwark on stream in “a safe and timely manner.”  The first gas from A2 is on track to be delivered by year-end, subject to stimulation progress and operational risks to final hook-up and commissioning, while the A1 well will be completed after the first gas from A2 is achieved.