Petrobras has broken a new domestic record for exploratory drilling by reaching a water depth of 2,990 m. This was achieved in February while drilling a well in the Moita Bonita area of Sergipe-Alagoas Basin, 92 km from the city of Aracaju.
Only six exploration wells across the world have exceeded this depth. Of the 50 deepest wells in the world, Petrobras has drilled 15 (30%) of them.
The deepwater discoveries made in Sergipe-Alagoas Basin since 2010 have revealed a new extremely promising exploration frontier. The drill stem test, conducted in 2012, confirmed the presence of 41º API oil (light, high-quality crude) and good reservoir productivity.
Eight wells in the region are more than 2,700 m deep, all drilled within a period of three years. This is a significant achievement given the adverse local drilling conditions, with intense ocean currents, deepwater and the need to use more robust drilling equipment such as blowout preventers.
In addition, Petrobras has started production on platform P-61 in Papa Terra field, located near the southern perimeter of the Campos Basin (State of Rio de Janeiro), 110 km off the coast of Brazil and with a water column of 400 to 1,400 m.
Moored in waters 1,200 m deep, the P-61 completes the production system for the Papa Terra field, operating alongside the P-63 FPSO (floating production storage and offloading), commissioned on 11 November 2013.
14 production wells will be connected to the P-61, and the well currently in operation is the PPT-16. Five production and six injection wells are interconnected to the P-63, and a further five injection wells will be added.
Output from P-61 is transferred via flexible lines to FPSO P-63, capable of processing 140,000 bopd and 1 million cu m (m³) of gas, and injecting 340,000 bbls of water. Shuttle tankers transport the oil from the field and surplus gas not consumed on the platforms is injected into a nearby reservoir.
The P-61 tension leg wellhead platform is connected to a tender assisted drilling platform and is equipped with a drilling and well completion rig. This is the first time a platform of this type has been used in Brazil. P-61 is connected to dry completion wells, which means that the well control valves are onboard the platform and not on the seabed.
Wells are connected to the P-63 via subsea flexible pipes with electric heating, a system known as an integrated production bundle, and the field’s 18 production wells feature subsea centrifuge pumps.
The topside of P-61 was built at the Keppel Felds shipyard in Singapore. The hull and mating operation (joining hull and topside) were completed at the Brasfels shipyard in Angra dos Reis (Rio de Janeiro State).
With reservoirs containing 14 to 17 API crude at considerable water depth, developing the Papa Terra field has been a challenging project for Petrobras, requiring many different innovative solutions.
Papa Terra field is operated by Petrobras (62.5%) in partnership with Chevron (37.5%). Chevron’s participation in developing this field has been an important factor, given its experience with projects of this nature.