LONDON -- Production has now hit over one million barrels of oil at the Parque das Conchas fields offshore Brazil, according to operator Shell.
A network of wells and pipelines connect the field’s reservoirs, which are up to 20 km (12 mi) apart. In a technical first, oil and gas are separated on the seabed before electric pumps push the oil upwards from the low-pressure reservoirs to a specially converted production vessel on the surface that stores it for shipping to shore. The reservoirs of Parque das Conchas are connected through a single production process centered on the converted vessel.
Production from the fields — currently ramping up — is the latest step in Shell’s strategy of delivering an additional 1 MMb/d of oil and gas production in the coming years.
The Parque das Conchas project, formerly known as BC-10, uses a floating production, storage, and offloading vessel (FPSO) with the capacity to produce up to 100,000 b/d of oil and 50 MMcf/d of natural. Shell is the operator with a 50% share; partners Petroleo Brasileiro (Petrobras) holds 35% and India’s ONGC Campos holds 15%.
To combat the low pressure in the reservoirs, Shell installed 1,500-hp electric submersible pumps on the seabed. The oil travels through specially-developed steel pipes that are flexible enough to move with the ocean’s persistent swell.
Production comes from the Abalone, Ostra, and Argonauta B-West fields lying at depths of between 950 m to 2,500 m (3,117 ft to 8,202 ft) below the seabed. The first phase of the project, which is currently onstream, involves nine producing wells. A second phase currently in planning will focus on the Argonauta O North field.
The field’s resources lie in small- to medium-sized reservoirs under a seabed terrain made unstable by shifting sands. To prevent sand, mud, and shale from falling back into the well while drilling, Shell pumped in a mix of synthetic oil with additives under high pressure to hold the hole open.
Some of the oil at Parque das Conchas has high gas content. To prevent it from entering the pumps and causing damage, Shell installed machines to separate the oil from gas on the seabed, rather than on a surface platform or onshore. Instead of burning this gas off, it is being pumped back into the Ostra field for storage until construction of a gas export pipeline system is complete.
“Developing breakthrough technologies and being successful in Parque das Conchas will allow the development of other deepwater projects in Brazil and elsewhere,” says Steven Grant, subsea team lead of the project at Shell Brasil.
Video courtesy of Shell