May 15 (1) Visit to Petrobras Research Facility in Rio de Janeiro
Lauren Miller, Alex Swithers and Rachel Woody
Petrobras is Brazil's largest petrochemical and petroleum company, grossing nearly 86 billion dollars a year. Founded in 1953, the company has made major technological contributions to the oil industry. The company has been leader in offshore exploration and production. More recently, it has focused on extraction methods and production systems for reservoirs located under sea salt beds (the so-called Pre-Salt reservoir that was recently discovered). It is estimated that the shores of Brazil hold a reserve of nearly 80 billion barrels, making them one of the 15 largest oil producers in the world. A publicly traded company, Petrobras is primarily state-owned. State oversight helps the company navigate Brazil’s strict regulation and approval process.
Petrobras focuses on finding, extracting, refining and exporting petroleum and petrochemicals around the world. They advocate environmental stewardship and emphasize the need to produce in eco-friendly ways. Petrobras invests in wind and small-scale hydroelectric power and uses solar power to run some of the company’s petroleum facilities. In the long term, Petrobras seeks to transform from a petroleum to an energy enterprise.
The company began offshore production in 1954 in the Dom João Mar oil field at a depth of merely 3 meters. In the 1980's, the company progressed to more advanced methods of production and to greater water depths, exceeding 800 meters. The Campos Basin, accessible only by deepwater drilling, became the primary production region for Brazil and continues to provide oil resources to much of the world. Currently, Petrobras has the ability to drill in water as deep as 1886 meters, as illustrated by the Roncador production system.
Several methods of offshore drilling are in use around the world, but each system requires a method of anchoring the platform to the sea floor. While some systems are rigid, such as a fixed production platform, others are mobile, such as the semi submersible production platforms, whose legs are raised or lowered to proper height. FPSOs (floating production, storage and offloading systems) and semi submersible systems are used by Petrobras in the Campos Basin and Roncador field, respectively.
Cables and risers are used to stabilize the platform of a floating structure. Complex stresses from currents must be accounted for when designing these stabilization methods. The cables take the shape of a catenary rigid riser. For a mooring system of semisubmersible structures, an angle of 45 degrees is used to support horizontal and vertical containment. Both polyester and steel cables are used together to give a better response to the wave, current, wind, and other oscillation and displacement forces. These are typically used for high water depths, as seen in the P-35 system. Ideally, it utilizes 8-12 mooring cables adequately designed for each situation.
Unfortunately, with greater depths came greater challenges in petroleum production. The engineers at Petrobras met these challenges by developing new methods of sensing, analyzing, anchoring and stabilizing. New tools help engineers find the optimal location for new platforms, and develop the right stabilization and anchoring methods. Some vital data collection methods include Doppler accustom currentometers, anemometers, satellites to sense water temperature, and new soil tests to characterize the ocean floor. Custom software was specifically developed to organize, analyze, and model the parameters collected by these methods to facilitate the launch of platforms and decide where to drill based on depth, current and weather.
A successful example of this process is Petrobras’ FPSO ship with torpedo piles, moored off the Campos Basin. To install this platform, engineers conducted a wide array of tests to ensure the stability of the mooring area. Isotopic dating shows the change in topography over thousands of years, while a probabilistic analysis of these data helps predict the likelihood that the ocean floor will move again in a significant way. Creep analysis is performed to estimate the nonlinear effect of creep in the soil to see if permanent deformation occurs. Creep, deformation under constant stress, may over time overload components associated with oil production, such as pipelines. Use of an FPSO also allows Petrobras to opportunity to recycle and refurbish older tankers for new uses.
After listening to the technical presentation, our class toured and experienced Petrobras’s $250,000 virtual laboratory. This lab allows users to experience firsthand what it feels like to be on an oil platform through a sophisticated 3D visual display. 3D Projectors generate images of a platform or ship on three walls and the floor in order to simulate the experience of walking through the ship. Students were able to get a feel for the cramped nature of the ship while exploring some the technical equipment onboard.