In 2007, the Brazilian government revealed that largely state-owned Petrobras had discovered massive quantities of pre-salt light oil and gas. We are talking about an estimated 100billion barrels.
At first, the specialist press, particularly American, raised doubts about whether Petrobras could develop the technologies needed to exploit hydrocarbon resources beneath up to 3,000m of ocean and masked by layers of salt that can be as much as 2,000m thick.
But the company did it.
Petrobras proved that its internationally renowned R&D Centre, CENPES, had an “Einsteinian” brain and now the pre-salt area is beating records with oil output already above 400,000 bpd.
By 2020, the company forecasts that pre-salt alone will double the current average crude output of some 2million bpd.
Petrobras president and CEO Maria das Graça Foster told TV Brazil that by 2020, production will reach 4.2million bpd and that 52% would come from the pre-salt reserves, located 6,000m (19,000ft) beneath the sea floor offshore south-eastern Brazil.
As a result, Brazil is on its way to join the elite club of the five largest oil producers in the world, despite going through financial scandals along the way.
In 2007, then President Luis Ignacio Lula da Silva referring to the pre-salt discoveries said: “God is Brazilian and he moved to Brazil.”
What seemed like a demagogic statement, in the largest Catholic country in the world, is becoming a reality.
A graphic measure of the enormous progress already made is that Brazil today offers the world’s largest market (around 50%) for pipelay vessels. Of some 40 such vessels operating or being built (largely to European account), 27 have been contracted by Petrobras to operate in Brazil. And the current dayrate for such vessels is more than $3million!
Co-operation with institutions such as the Federal University of Rio de Janeiro (UFRJ), national and international universities; National Petroleum, Gas and Biodiesel Agency (ANP) and companies like FMC Technologies, Subsea 7 and others, enabled Petrobras to find solutions to many problems and challenges in subsea development that might have taken much longer if the corporation had worked alone.
“We could not have advanced in this project (pre-salt) conventionally, developing the production individually,” said exploration and production director José Formigli, speaking about the plan for developing Santos Basin pre-salt resources.
Infrastructure challenges are directly related to the harsh environment where the pre-salt discoveries have been made.
During and after installations of production systems, specific challenges are strong deepwater currents, irregular and unstable seafloor, equipment corrosion and equipment failure, and more.
In terms of wells and subsea, Petrobras faces problems associated with hydrate formation and, in some cases, the need for sand-related well workovers; also more conventional workovers to replace gas lift valves and electrical submersible pumps.
Autonomous monitoring equipment is very important. This is because, over the years, Petrobras has installed a huge amount of deepwater/ultra-deepwater subsea equipment and underwater pipelines. In many cases it is impossible to inspect them with intrusive techniques, thus the need of advanced underwater inspection tools.
CENPES is focused on advancing technologies to face these challenges; looking for and devising practical solutions across a wide front, including riser and flowline (SURF) components inspection, various subsea structures, Xmas trees, and an array of umbilicals, control systems and subsea piping.
“Development of subsea systems and equipment, new or optimised, are vital to produce in deep and ultra-deep waters, pursuant to concepts of compact subsea oil, water and gas separation, re-injection of produced water into the seabed, gas-lift technology enhancement, subsea gas compression, oil boosting from the seabed, and a new generation of submersible electric pumps,” said engineer Marcos Assayag, a director at CENPES.
While huge progress has been made locally over the past 10 years or so, CENPES is even more relevant today and is, for example, working on new and more efficient systems, methods and procedures for deepwater subsea construction, for the many deepwater pre-salt developments planned for the coming years.
This includes the Libra pre-salt field in the Santos Basin. This project alone is expected to require some 60 to 90 support vessels, many of which to be exclusively used for subsea construction.
Libra alone is thought to have recoverables in the range 8-15billion barrels. Bear in mind that, discounting this development, Brazil’s proven oil reserves are only 14billion barrels.
The Libra consortium, comprising operator Petrobras (40%); Shell (20%); Total (20%); CNOOC(10%); CNPC (10%), has approved the 2014 working and investment plan, with capital expenditure in the range $400-500million.
The block’s current four-year exploration phase, which began last December, includes 3D seismic acquisition, two exploratory wells, and one extended well test.
Partnerships
Aside from subsea infrastructure, there are many other critical technology challenges including the need for well testing innovation.
Last year, Schlumberger Brasil proposed to optimise Petrobras deepwater well test operations, using a real-time communication solution on a well in the pre-salt Santos basin to provide important information about well deliverability and reservoir characteristics.
The bottom line is that downhole test operations can be especially critical in high-cost, high-risk environments such as deep water.
The candidate well tested with the wirelessly-enabled “signature” gauges is located more than 250km (150 miles) offshore. Water depth exceeded 1,981m (6,500ft) and the depth of the target zone was greater than 3,350m (11,000ft).
This wireless solution allowed Petrobras to interact with downhole equipment, manage wellbore events, and refine the test in real time. In this well, running the wireless system took less than six hours of rig time.
Signature quartz gauges ran continuously for 568 hours – longer than three weeks – to provide data crucial to optimising well test operations in real time.
Petrobras reservoir engineers were able to observe perforating guns’ impacts on pressure and confirm dynamic under-balance, compute productivity when the well was flowing and to obtain insights into reservoir parameters.
Conventionally, in many well test operations, downhole data is recovered using a system that is run on electric line and deployed during the buildup period. This is time consuming and poses safety risks involving equipment handling, high pressures, and cables across valves.
$1billion agreement
The Guará and Lula fields are among the large, ultra-deepwater, pre-salt discoveries made by Petrobras in the Santos Basin. Among Subsea 7’s Brazilian operations, the Guará-Lula NE project contract is a milestone $1billion agreement.
To date, this is the largest EPIC (engineering, procurement, installation and commissioning) – SURF (subsea, umbilicals, risers and flowlines) contract awarded in Brazil.
Subsea 7’s remit covers the engineering and installation of four decoupled riser systems, featuring large submerged buoys supporting 27 steel catenary risers (SCRs) of 3.9km length.
The system also includes: four submerged buoys each weighing about 2,000t to be installed approximately 250m deep, buoy foundations and associated tethers; SCRs, associated 21 pipeline end terminations (PLETs) of which 18 are 7.5-inch production lines, three 9.5-inch water injection lines and six 8-inch gas injection lines; 7.5-inch production lines, three 9.5-inch water injection lines and six 8-inch gas injection lines; 27 anchor suction piles and four monitoring systems for buoys and SCRs.
Toward the end of last year, Subsea 7 secured contracts with Petrobras worth $600million for deployment of its pipelayers Seven Mar and Seven Condor on a day-rate basis for approximately three years. Seven Mar is now at work and will be joined by the Condor in Q3 this year.
$650m deal for FMC
Another contract that absolutely emphasises the huge importance of the pre-salt and of the need for innovation is the $650million deal with FMC Technologies and signed on September 10, for the supply of subsea manifolds.
The scope of supply includes the delivery of up to 16 subsea manifolds.
The initial order from the agreement includes 11 manifolds, tools and controls. This order is in addition to the three subsea manifolds of identical design ordered by Petrobras earlier this year.
Under local content rules, the equipment will be engineered and manufactured in Brazil with delivery scheduled to begin next year.
FMC has significant prior experience of supplying systems to Petrobras.
The prime example, Marlim, Petrobras’ largest field in the Campos Basin, is the fifth field in the world to utilise FMC Technologies’ subsea separation system.
Located 110km (70 miles) offshore Rio de Janeiro, it was once considered the world’s largest subsea development, with 129 wells and eight floating production units (FPU), devoted to the extraction of oil and gas.
Marlim is spread out between depths of 640-2,590m (2,100-8,500ft). The separation system is at 900m (2,950ft). This is the first system worldwide to include deepwater subsea separation of heavy oil and water, with sand removal systems and reinjection of water to boost production in this mature field.
FMC supplied the subsea separation and pumping system, utilising a novel pipe separator design, licensed and developed in cooperation with Statoil.
The system is being engineered by FMC’s operations in Brazil, Norway and the Netherlands with final manufacturing and integration activities performed at the company’s Rio de Janeiro facility.
The foregoing is just a taste of what is happening offshore Brazil where subsea frontiers are being challenged probably more vigorously that anywhere else in the world, including the US Gulf of Mexico and West Africa.
Peter Howard Wertheim is a veteran oil/gas journalist based in Rio de Janeiro, Brazil. He can be reached at: peterhw@frionline.com.br
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