By an OGJ Online Correspondent
HOUSTON, Oct. 2 -- Petroleo Brasileiro SA (Petrobras) plans to resume development of its offshore Roncador field with installation of an advanced production system in the same area where its P-36 platform, once the world's largest, sank earlier this year.
To keep Brazil on track with its goal of achieving oil self-sufficiency by 2005, Petrobras also anticipates bringing Marlim-South field on stream and accelerating production in the Albacora-East, which are also in the Campos basin off Rio de Janeiro state.
Petrobras officials said they are working to develop all three fields as part of their goal to produce 1.9 million b/d of crude by 2005. Proven reserves for the trio are 3 billion bbl of oil and 44 billion cu m of gas.
The new Roncador production system, christened module 1A phase 1, is expected to start production in August, with an installed capacity of 90,000 b/d of oil. It will be installed with the floating production, storage, and offloading (FPSO) vessel Brasil, chartered from Single Buoy Moorings Inc. (SBM), a Monaco-based company that operates Espadarte field FPSO in Campos basin.
The P-36 platform, a converted semisubmersible rig, sank after an explosion that killed 11 workers (OGJ Online, Mar. 21, 2001).
"We shall use known technology and engineering systems and will therefore be able to start production in a short space of time, since we won�t have to search for new technology. The FPSO charter contract was signed for a 5-year period," said Cesar Palagi, general manager of the exploration and production unit at Petrobras.
Five of the six wells that operated with the P-36 will be connected through the FPSO.
Despite the loss of the P-36, the wells, wellheads, and subsea trees remained intact, enabling the field to be reactivated without large investments in subsea systems, said officials.
As the platform slowly sank, all well lines were cut so that the lower segments connected with the wellheads could be reclaimed, although the risers and upper portions of the lines could not.
"When we cut the lines, the pressure of sea water entering them forced the oil to the other end connected to the P-47 platform. So, as well as avoiding environmental threats, which were our first concern, we also recovered a certain amount of oil," Palagi said.
"In the case of the production wells, rigs were placed over the wellheads. We opened the wells at the trees, injected hydrogen, and took the oil from the lines to the rig. Now we have sealed the wells," he said.
When a new platform is installed, workers will connect those lines to a new riser system and reestablish production. Officials said Roncador's technology, especially its anchor system, would facilitate installation of the new unit.
Petrobras has started work on the Roncador 1A phase 2 module, described as the definitive system to replace the P-36. A team is working on development of new riser technology for installing the 1A phase 2 module in 1,700 m of water, compared to 1,360 m for the P-36.
"We are working on this project this semester and expect that the system will be producing by 2004. In 2005, the [two phases of] Module 1A will be producing 180,000 b/d of oil, about 20% more than would be produced by the P-36," said Palagi.
Contracts for Roncador field products and services have been diverted to Marlim-South, which is due to begin production in 2005. It will operate in the Roncador configuration with the P-38 FSO receiving production from the P-40 platform.
Most of the equipment to be used at Marlim-South has been bought, but Petrobras officials said they will buy equipment for Albacora-East, including 36 christmas trees. It is due to start up in 2003.
Although Petrobras' fiscal 2001 production was some 30,000 b/d less than forecast, company officials predicted it will return to normal production levels, with investments of $1 billion each in Marlim-South, Roncador, and Albacora-East fields.