Petrobras to decommission Brazil's first pre-salt commercial FPSO

Petrobras is set to decommission the first definitive production system of Brazil’s pre-salt. 

The Cidade de Angra dos Reis FPSO started operating in 2010 in what was then called the Lula field, before it was renamed Tupi.

Located in the Santos basin, Tupi lies 286km off the coast of Rio de Janeiro state, in waters 2,140m deep. It is Brazil's top oil- and gas-producing field.  

The Angra dos Reis decommissioning project marks a new era of Brazil's prolific pre-salt reserves, which were mostly discovered in the first decade of this century and are entering a stage of declining production. 

The decommissioning of the platform is being driven by the approaching expiration of Modec’s FPSO charter contract, which ends in 2025, with a possible extension to 2030.

Angra dos Reis is linked to Tupi via 34 flexible risers (pipelines and umbilicals), spanning approximately 266km, as well as a gas pipeline that is connected to the Santos basin gas network.

The FPSO's flexible lines are anchored by 41 torpedo piles embedded in the seabed, and more than 250 floats support the gas pipeline connecting to the platform.

The Tupi field has 13 wells, with 12 still connected to the FPSO by at least one line. The decommissioning program includes the removal of 13 wet Christmas trees (WCTs) at the wellheads. Additionally, several sections of flexible and umbilical pipelines, currently left on the seabed with disconnected ends, are also included in the decommissioning.

Angra dos Reis’ mooring system consists of approximately 14km of steel mooring lines (top and bottom) and 66 km of polyester cables, with an estimated combined weight of 8,785t.

Well Abandonment

Permanent abandonment of wells will be performed with dynamic positioning rigs, ideally in two phases: an initial light workover phase, followed by a heavy workover phase. 

In certain cases, wells may be abandoned through tubing, allowing completion in a single phase without removing the production column.

Once de-anchored and removed from the Tupi field, the destination of the FPSO will be determined by Modec, in accordance with all applicable national and international regulations.

Production overview

According to Brazil’s oil and gas regulator ANP, the Angra dos Reis FPSO produced 40,394b/d of oil and 2.4Mm³ of natural gas in August.

During the month, Tupi’s average daily output, accounting for all FPSOs operating in the area (Itaguaí, Mangaratiba, Saquarema, Maricá, Paraty, P-66, P-67, and P-69), reached 832,602b/d of oil and 43.2Mm³/d of gas, putting Tupi ahead of the Búzios field, which produced 605,555b/d of oil and 25.8Mm³/d of gas.

While Búzios is expected to surpass Tupi with new FPSOs scheduled to come online in the coming years, Tupi is likely to undergo a revitalization program to enhance hydrocarbon recovery. The proposed plan, still pending approval by Petrobras, includes the installation of a new FPSO through an engineering, procurement, and construction (EPC) contract.

(The conceptual decommissioning plan for Cidade de Angra dos Reis, obtained by BNamericas, can be downloaded in the Documents box).