Marine Technology Reporter Blogs - production

Deepwater flow assurance should always be considered from an integrated standpoint, taking into account the well, reservoir, and production angles to make sure the full range of fluid scenarios and compositions are examined, and to avoid costly resampling and re-evaluation after systems are built. Production fluids interact with the reservoir, well, pipeline, surface facilities, and the environment. All these impact flow assurance, leading to potential issues with hydrates, wax, asphaltenes, scales, slugging, emulsion, foam, sand, and corrosion. Deepwater flow assurance requires a full understanding of these interactions and a multi-disciplinary approach to managing them. Modern simulation software allows such an approach to be integrated efficiently into asset team workflows.

Well stimulation is a well intervention performed on an O & G well to increase production by improving the flow of hydrocarbons from the drainage area into the well bore. The assortment of drilling fluid pumped down the well during drilling and completion can often cause damage to the surrounding formation by entering the reservoir rock and blocking the pore throats (the channels in the rock throughout which the reservoir fluids flow). Similarly, the act of perforating can have a similar effect by jetting debris into the perforation channels. Both these situations reduce the permeability in the near well bore area and so reduce the flow of fluids into the well bore. A simple and safe solution is to pump diluted acid mixtures from surface into the well to dissolve the offending material.

Flow assurance is a relatively new term in oil and gas industry. It refers to ensuring successful and economical flow of hydrocarbons from reservoir to the point of sale and is closely linked to multiphase flow technology. Flow Assurance developed because traditional approaches were inappropriate for deepwater production due to extreme distances, depths, temperatures or economic constraints. The term “Flow Assurance” was first used by Petrobras in the early 1990s (Garantia do Escoamento in Portuguese), meaning literally Guarantee of Flow, or Flow Assurance. Flow assurance is an extremely diverse subject, encompassing many specialized engineering disciplines.

During the production phase of a reservoir, natural phenomenon, such as movement of fluids, changes in pressure and stress in and around reservoirs occur. In high-pressure reservoirs, pressure depletion during production is associated with compaction within the reservoir causing stretching or extensional stresses in the overburden and underlying formation. This causes variation in velocities and formation thickness, which can be observed as 4D time shifts between successive vintages. Tracking the movements of fluids due to production, for example, gives valuable information about the depletion of a field, and can indicate areas of bypassed oil or gas.

The launching of the Rio Grande Naval Complex completes another key project for pre-salt production, as the complex will house the hybrid pre-salt FPSO production line, which already has an order book for 8 units. Petrobras has launched today the Rio Grande Naval Complex, in the city of Rio Grande, southern state of Rio Grande do Sul. The complex is considered so vital to the Brazilian pre-salt production that the outgoing president of Brazil, Luiz Inácio Lula da Silva was in attendance. The complex consists of a 430,000 m² infrastructure designed for the construction and repair of offshore units for the O&G industry. The complex will be capable of building drillers and production rigs.

The MODEC owned and operated FPSO Cidade de Angra dos Reis MV22 has been moored in 2,150 meters (7,053 ft) at its final operational location over the giant Tupi area in the Santos Basin. O&G production operations will begin in a few weeks after on-location tests.MODEC converted the VLCC "M/V Sunrise IV" into an FPSO at the COSCO (Dalian) Shipyard Co., Ltd. (“COSCO Dalian”) in China. The FPSO is classified by ABS as 29.7 meters in depth, 58.00 meters in breadth, and 318.46 meters in length. The conversion from VLCC to FPSO involved steel fabrication, module installation and integration, the installation of cables, pipe and equipment.

Ativatec is a Brazilian company specialized in subsea technology and robotics engineering. The company was born at the Genesis Incubator at the Catholic University of Rio de Janeiro (PUC-Rio) in 2005. Today, Ativatec offers subsea services for Petrobras at the Campos Basin. Ativatec has a very good track record in developing new subsea technologies in partnership with government research institutes and universities such as FINEP, FAPERJ, PUC-Rio and Petrobras. Prizes and recognition from Petrobras for the services and products developed for the National Operator along the last 9 years, has earned Ativatec a preferred partner status with Petrobras and the company is recognized as one of the main Brazilian subsea robotic companies in the market.

Petrobras’s P-58 FPSO started operations at Parque das Baleias, off the state of Espírito Santo, on the north sector of the Campos Basin through well 7-BFR-7-ESS, another pre-salt producer, which is showing an excellent productivity. P-58 is part of the North project of Parque das Baleias, which encompasses production from Baleia Franca, Cachalote, Jubarte, Baleia Azul and Baleia Anã plays. P-58 is moored approximately 85 km off Espírito Santo, at a water depth of 1,400 meters. In the upcoming months, 15 production other wells, being 8 pre-salt and 7 post-salt, as well as 9 injection wells will be interconnected to it through 250 km of flexible pipelines and two subsea manifolds.

The Franco pre-salt field, which is located southwest of the massive Libra field that will be auctioned in October 21st, originally had been forecast to contain 3 billion barrels boe of recoverable light oil. In light of new studies, the Franco pre-salt field is now believed to contain recoverable oil volumes equal to or superior to the Libra pre-salt field, something hovering around 10 billion barrels boe. This is excellent news for Petrobras, which is in the process of making major exploratory, production and infrastructure investments and desperately needs new capital. The reason it being excellent news has nothing to do with oil auction…

As the time for the first pre-salt bidding round approaches, solid data begins to appear related to production forecasts and assets needed for the field’s development. Brazil’s National Petroleum Agency (ANP) has confirmed that the first pre-salt bidding round will take place in October 2013 in Rio de Janeiro and the rules concerning it have already drawn criticism from potential operators. ANP maintains that these rules will not be changed and has come forth with information concerning the field’s development. According to thr ANP, Libra is expected to produce first oil in 2018, that is, 5 years after the winning consortium signs the E&P contract for Libra. This contract will be signed by November 2013.

Based on project experience, research, and joint industry development work, DNV issues a number of pipeline codes. These comprise service specifications, standards and recommended practices, and are highly regarded within the international pipeline community. The DNV OS-F101 ‘Offshore Standard for Submarine Pipeline Systems’ provides acceptance criteria and design procedures for pipelines. The standard applies modern limit-state-design principles with ‘safety classes’ linked to consequences of failure. The DNV standard is complemented by several recommended practices (RPs), which give detailed advice on how to analyze specific technical aspects according to stated criteria.

Brazil has been investing in a major effort to increase its exploratory O&G campaign along the countries coast and also inland where major gas reservoirs have been recently located. Unfortunately, this is still not enough as presently Brazil is exploring only 4% of its areas with O&G potential. Of the 7,5 million square kilometers of sedimentary basins located in the country, only 7% have actually been researched, including all the recent major pre-salt discoveries. This points to major untapped O&G potential in the country, the numbers are impressive and point to a need to increase even more the research and exploration of the huge areas still untouched. This further increase in exploration brings various safety and environmental risks along with it.

Petrobras will launch a world first floating offshore oil terminal in order to be able to transfer oil to oil tankers offshore, beginning in 2014. Up until now the oil had to be transported through pipelines from the offshore rigs to the coast where tankers would load up the oil. It is expected that this new system will decrease oil transportation costs as tankers will be relieved from the high Brazilian port taxes, the tankers will also save up on their own bunker oil as the distances they will have to travel will decrease. The new system should be used mainly for export oil and will also probably be a hub for tankers coming to fill up on deepwater pre-salt oil.

Petrobras has set plans to spend $5.6 billion through 2016 to increase output at the Campos Basin mature fields which have had decreased outputs for some time. Most post salt fields at the Campos Basin have been in production since the 1980s, some of which have been major producers. A steep decline in production began around 2009, not only due to the aging fields having low reserves but also because of lack of investments in operational resources and equipment for the older fields. The national operator will invest $1 billion in new money and spend $4.6 billion in operating costs to boost efficiency in the offshore Campos Basin operating unit to historic levels of about 90%, up from 72% in the first quarter of 2012.

The group that will be awarded the construction contract for this novel offshore LNG production unit will be known by October 31 Petrobras is keen to begin construction of the unit as it considers offshore natural gas liquefaction vital to guarantee a efficient output for the Santos Basin pre-salt gas. Many of the Santos Basin pre-salt fields are located over 300km from the coast, which convinced Petrobras to seek other options in order to deliver the gas to the market. Normally gas is transferred from wells to the coast through underwater pipelines but with such distances involved and with many of thereservoirs located in deep water…

The advent of reliable subsea processing has taken a considerable time to develop. For a few years now, it has been looked at as a vital solution for deepwater O&G development. Subsea processing technology was first developed to overcome challenges posed by extremely deep wells but in time it has become a proven solution in mature fields by decreasing the amount of equipment on the surface, therefore lowering operational costs and of course by boost diminishing production from mature wells, normally through re-injection of fluids, such as water, into the wells to increase the pressure inside the well. It is also an important solution in locations where harsh surface weather conditions make it extremely risky to have an anchored production plant.

After a nearly perfect drilling campaign on various fronts in 2010, OGX start 2011 with new discoveries in the Campos Basin. Although there was much skepticism at the start of OGX´s creation in 2007, after last year´s performance, the new Brazilian operator, which was created by Brazilian businessman and investor Eike Batista adding to the portfolio of his EBX Group can now easily be considered as a good investment, especially for those who bought in early. Eike´s strategy to hire and partner with Petrobras´s extraordinary geologist and executive Paulo Mendonça was vital not only to gain market value as to bring in deep knowledge of where do drill and how to plan the E&P campaign. It´s important to not that Petrobras´s exploratory success rate more than doubled after Mr.

The importance of increasing the number of maintenance rigs in decreasing accident risks on older production rigs should not be underestimated, and Petrobras will need to speed up their construction, as there is no shortage of old rigs out there.Petrobras is finally increasing its investments on Maintenance and Security Units “Unidades de Manutenção e Segurança” (UMS). The new unit UMS Cidade de Arraial do Cabo, will be supplying logistics support for production rigs at the Campos Basin, its main function will be to increase safety on the rigs through maintenance and renovation in order to increase the life expectancy of these rigs.

The oil industry in Brazil finishes the year with intense activity on all fronts and the efforts are massive. However the risks taken on the deepwater projects and older production rigs may still lead to major spills if not kept in check.Petrobras recently discovered light oil in sandstones reservoirs in the post-salt section of the Espírito Santo Basin. The discovery was the result of the drilling of the 1-BRSA-882-ESS well, known as Indra, located within the BM-ES-32 Block. Petrobras holds a 60% stake and is the operator, Statoil holds the remaining 40%. It is located 140 km from the city of Vitória and was drilled to approximately 3,850 m, from a water depth of approximately 2,100 m, and is the deepest oil discovery at Espírito Santo Basin.

Flexible risers are being extensively used worldwide for deepwater O&G extraction, offering many advantages over rigid risers. However concerns still exist about the overall safety of the system, especially concerning failures leading to hydrocarbon leaks in the ocean environment.The flexible risers being used in deepwater are designed to work for a period of around 20 to 30 years, which is the expected lifetime of an O&G field. A flexible riser failure could happen due to a number of reasons, such as hostile environmental hazards and material fatigue and if the failure is catastrophic, it could lead to high economic and environmental consequences. Flexible risers comprise multiple layers, and the main layers of concerns are the tensile armor layers which exist to withstand tension loads.