Petrobras stepped into the third millennium with an ambitious plan for offshore oil production. As a natural sequence of the most recent breakthroughs achieved in deep and ultradeepwater activities, Petrobras now prepares itself to operate in an even more difficult scenario in Campos Basin: deeper water, up to 3,000 m (9,800 ft), with heavier and more viscous oils. The increase in the ocean depth where it operates will bring challenges in the areas of drilling and completion, naval structures and mooring, risers and flowlines, and subsea equipment. Because of the heavier and more viscous nature of the crude oils found in this environment, several other aspects will have to be addressed: well completion technique aiming t increasing per well productivity, i.e., longer horizontal wells with larger borehole diameter, and sand production control, improved flow assurance technique and artificial lift to deal not only with hydrates and waxes, but also with stable emulsions and ultra-viscous fluids in the subsea production systems. Several fields already in production are or will soon be in mature phase, when substantial water production is expected. Also, the productivity of the fields will decrease, making harder to keep the production profitable for long time. This article describes the Petrobras plan to face each of these new challenges. The ultimate goal is to develop production systems capable of making profitable the exploitation of heavy oil reservoirs in ultra deep waters, in spite of tougher production conditions. Introduction Campos Basin production history dates back to 1977, when the first subsea production systems were put in operation. Details can be found in reference [1]. Since the very beginning, the technological challenges to produce the discovered fields were significant. Sea depths of 120 m (390 ft), considered deep then, already posed huge efforts for Petrobras. Innovative concepts such as the atmospheric pressure wellhead cellars and manifolds, and all subsea systems were examples of novel technologies tried out in Campos Basin. Through the implementation of aggressive R&D programs, such as PROCAP and PROCAP-2000, Petrobras was able to design, construct and build production systems using high-tech and innovative solutions to operate in Campos Basin, in water as deep as 1,870 m (6,100 ft), before the end of the 20th century. Many fields such as Marlim, Albacora, Barracuda andCaratinga were developed using the technologies resulted from the PROCAP effort. Several of these offshore fields are now entering advanced production phases, in which, an expected larger amount of water are to be produced, bringing a new set of problems to be dealt with. With its continued effort to expand business in Brazil, the Company still holds considerable portfolio of fields to be developed, with large proven reserves. Roncador, Marlim Sul, Marlim Leste, Albacora Leste and Jubarte are examples of fields under development. They all lie in deep and ultra-deep waters, and hold relatively heavy (less than 19° API or viscosity higher than 10 cP @reservoir) crude oil.
During the past 20 years, driven by the national economical and political pressures caused by the several petroleum crisis of the 70s and 80s, Petrobras has had to innovate in order to increase the Brazilian oil output. The major problem was that the large Brazilian oil reservoirs were all located offshore in water considered too deep, at that time. The water depth was 120m, the distance to shore was more than 100 km, and the estimated production rate was around 7 times higher than in the Brazil Northeast platforms. The adopted solution was based on the international technology available, that is, using fixed platforms. That was certainly a tremendous change in what has been done before, and, certainly, it was the first step to a new era of production facilities. The use of conventional technology would demand both a long lead time to the first barrel and the resources were not compatible with the urge of cutting down the oil import, and to the delicate country foreign cash flow balance. Petrobras had to dare trying new concepts using national technology in its own production facilities as a huge R&D lab. Examples of new production systems, equipment, process, procedures and approaches tried in Campos Basin is given throughout this paper. Past successes and failures that led to the currently used technology, as well as the more recently planned prototype testing programs are presented. Introduction The 1973 world oil crisis brought a tremendous economical impact on most countries, especially on those with strong dependence on imported oil. This led to the increase in investment on oil and gas exploration and production worldwide, including the search of new technology for producing fields located in hostile environment. The first oil discovery in the Camps Basin, in Brazil. occurred in 1974, just in the middle of the economical chaos created by the crisis, worsened by the country's unfavorable external payment balance. Bringing the newly discovered prolific oil province on to production, as fast and at the lowest cost as possible, became a key issue for Petrobras. The increased throughput would help reducing the burden of Brazil to manage its increasing external debts. The oil import was responsible, at that time, for a significant portion of the Brazilian payment unbalance. The country had to reduce its oil consumption and, at the same time, increase its oil production. The reduction would come with the introduction of alcohol fueled automobile, and the use of other alternative energy sources, while the increase would mainly come through the Camps Basin offshore development. The problem was to produce in conditions never experienced before. The Garoupa and Enchova Fields, the first ones in the Basin, located in 120 m depth, were already considered in deep waters, at the time.
Campos Basin, the main production province in Brazil, was discovered in 1974. It is located on the North coast of the Rio de Janeiro State and comprises an area of around 115,000 km2 (28,400 acres), as shown in Figure 1. The producing oil fields are between 70 and 150 km (43 to 93 miles) far from the seashore. It started its production on August 13th, 1977 with 10,000 bopd (barrels of oil per day) from the well 1-EN-01-RJS, which produced to a semi-submersible platform; this well has produced nearly 35 million barrels of oil until February 1998, when it was shutdown for economical reasons. Today, after more than twenty-five years of continuous operation, the overall production system comprises 13 fixed platforms and 24 Floating Systems distributed among 42 oil fields, which account for the production of 1.21 million bopd - which corresponds to more than 80% of Petrobras oil production, plus 18.9 million m3 of gas per day - or 43% of the gas production (as of December 2002). Such an evolution was supported by investments in exploration and production development, in deepwater technology developments and in continuous management improvement. This paper describes the main driving forces to exploit Campos Basin - especially its deep and ultra-deepwaters fields, the technological and production developments performed, the experience accumulated by Petrobras along these 25 years of operations as well as its contribution to the global oil industry. Introduction The 1973 world oil crisis brought a tremendous economical impact on most countries, especially on those with strong dependence on imported oil, such as Brazil. This led a worldwide increase in investments on oil and gas exploration and production, including the search of new technology for producing fields located in hostile environment. The first oil discovery in Campos Basin occurred in 1974, while Brazil was facing the economical commotion created by the crisis, worsened by the country's unbalanced external payments account. Bringing the newly discovered prolific oil province on to production, as fast and at the lowest cost as possible, became a key issue for Petrobras. The increased throughput would help reducing the burden of Brazil to manage its increasing external debts. The oil imports were responsible, at that time, for a significant portion of the Brazilian payment unbalance. The country had to simultaneously reduce its oil consumption and increase its production. The reduction would come with the introduction of alcohol-fueled vehicles, and the use of other alternative energy sources, while the increase would mainly come through the Campos Basin offshore development. The problem was to produce in conditions never experienced before. The Garoupa and Enchova Fields, the first ones in the basin, located in 120 m water depth (WD), were already considered in deep waters, at the time. The available field-proven solutions using fixed platforms were technically and economically feasible, but it would take years for its implementation, and the costs were relatively high. The country also had to limit the use of foreign services and goods to a bearable minimum, to not worsen the economical scenario.
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