Offshore drilling and producing technology of total company

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Kazakh-British Technical University

Faculty of oil and gas industry

The importance of the Offshore Province i n supplying a significant part of today's energy needs and an increasingly significant part of tomorrow's needs is unquestioned. The greatest uncertainty, however, is just how much of our future supply will come from the offshore areas and, from a total national viewpoint, what is the best way to develop and utilize the potential when balanced against all other alternatives .The evolution, present status and near term status of offshore drilling and production technology is reviewed and summarized. The application of this technology to the development of the petroleum potential of the continental margins (0 to 2500 meters) of the USA is discussed and illustrated . Some effects of hopefully accelerated offshore leasing are examined.

Besides course project includes 28 Figures, 2 patents, 5 articles.

1. New ways to monitor offshore environments

2. Subsea intervention system for arctic and harsh weather

3. Subsea Technologies for Tomorrow

4. Improving Deepwater Recovery

5. Improving Performance on Tomorrow's Mature Fields

Summary

The purpose of this paper is to help provide the answers to at least a part of these questions by summarizing quantitatively the industry's existing capability to provide offshore drilling and producing systems. I n doing so it will be instructive to show the evolution of the various segments of offshore drilling and producing technology and to show how we got to where we are today.

Without attempting to quantify the tremendous efforts , either in terms of manpower or dollars , I will show where technology stands as of today and where it will very likely be in the next four or five years more or less under existing momentum. I will also discuss how this technology i s related to the total potential of the continental margins of the U.S.A. The development of future technology will depend a great deal on the consistent progressive application of today's technology as well as the overall assessment of the rewards and benefits to be achieved by advancing the technology. Remember that technology is not only the acquisition and possession of scientific knowledge but more than that, it is the application of scientific knowledge. Let me bring t h i s point home. I am not aware of any field of scientific endeavor which has even possessed or purported to possess the "final" answer to a particular problem before attempting a solution . There have always been uncertainties and there always will be; but, the uncertainties diminish by orders of magnitude as soon as someone accomplishes the "feat". Then everyone jumps on the bandwagon and says,

"I knew it could be done!"

Ladies and Gentlemen, the Petroleum Industry, and more particularly the offshore segment of t h a t industry, is no different in this regard from any other field of scientific endeavor. Categorical guarantees just are not in the cards. There al question and often times the most significant problem then is what is the best possible assessment of the realities of a potential course of action; in other words, "Which experts should one believe?" And let 's face it, this is no small task because the issues are complex and interwoven and the experts are numerous.

Integrated French energy giant

Total is continuing to spread its wings as it focuses on liquefied natural gas (LNG), deep offshore developments, and heavy oil. The Company is seeking to maximize production from its existing fields, while at the same time boosting output from a raft of new projects it is bringing on stream over the next 5 years.

Total has ambitious plans to grow oil and gas output by 2% per year and it is trying to strengthen its upstream arm through exploration, partnerships, and targeted asset deals. Total is the fifth-largest publicly traded integrated international oil and gas company in the world and is divided into three business segments ? Upstream, Downstream, and Chemicals. It produces oil and gas in more than 30 countries, including Angola, Australia, Nigeria, Algeria, Canada, China, Russia, and Qatar.

1. New ways to monitor offshore environments

Recent progress in techniques to monitor regular and planned exploration and production discharges offshore is expanding environmental management options for E&P companies. New water column and sediment measurement methods help make possible informed environmental management decisions. Such monitoring methods can be particularly important as E&P companies look to work in sensitive and previously unexplored environments that test the limits of conventional monitoring.

In some cases, tried and true methods have only limited applicability in deepwater operations and arctic projects. Furthermore, emissions from long-term, regular discharges are the subject of increased focus in terms of effects in the sea and in application of the best available treatment technologies.

Marine environmental monitoring can apply to permits and licenses, validation of numerical models, regulatory reporting, and technology selection. Nearly all the environmental management of an offshore installation relies in some way on the data from marine environmental surveys. For example, the initial state of the seas surrounding a development are monitored for baseline data and, following start-up, monitoring of the sediment and water column is performed periodically to help ensure the good environmental condition. Also, technology selection can be validated, as in the case of a platform in Norway where water treatment engineers used a fish biomarker survey to demonstrate the effectiveness of improved produced water treatment. Therefore, good, reliable data that represent temporal and spatial variation are needed to meet these and other environmental management needs. However, monitoring in the marine medium is challenging and limitations often restrict the amount of data available. More and more oil and gas developments are located offshore. Nevertheless, with easily accessible oil and gas provinces already having been explored, future developments will take place in increasingly harsh environments, such as the west of Shetlands North Sea, deeper and deeper offshore as well as ice-covered arctic waters. The current focus is on innovation in techniques and materials that enable human access to those ever-more difficult targets. A prime example is the Swimmer system for which Cybernetix, Statoil and Total initiated a feasibility study in 2007. After 18 months, Total decided to study further the Swimmer concept for the offshore Angolan specific application. Swimmer is a vehicle that performs inspection, maintenance and repair of subsea production systems with enhanced versatility and responsiveness. It is a hybrid system composed of an AUV (Autonomous Underwater Vehicle) and a ROV (Remotely Operated Vehicle). As such, it can perform pipeline inspections in AUV mode and light interventions on subsea equipment by deploying its own embedded ROV operated from topside production facilities. This innovative vehicle is designed to reduce operational risks as well as operating costs as it does not call anymore for a ROVsupport vessels. It is engineered to remain on the seafloor for up to three months at a time, without any need for maintenance. Swimmer is undergoing further development to meet tomorrow's challenges - including deployment in arctic regions.

2. Subsea intervention system for arctic and harsh weather

SWIMMER is a new hybrid AUV/ROV subsea intervention system for light inspection, maintenance, and repair (IMR) operations on subsea production systems (SPS). One prime advantage is that it can carry out IMR operations on its own, without a field support vessel. Once the Swimmer AUV shuttle is resting on its docking station, the ROV can be controlled fully from surface facilities via the production control umbilical. The Swimmer's technical feasibility was shown in 2001 by full-scale sea trials. Since 2007, Total, Statoil, and Cybernetix have cooperated to develop a commercial version. Although the first application of this technology is earmarked for Total's Angola block 17 in late 2011, the partners are investigating use of the Swimmer system in offshore fields with extreme weather conditions. Swimmer not only can boost the flexibility and reduce the cost of operations for deep offshore fields, but also may become an enabling technology on ice covered arctic fields or in harsh environments such as the North Sea. The weather at these fields can prevent intervention vessels from operating for long periods, and is a personnel safety concern. In these conditions, the Swimmer's ability to remain deployed subsea for several consecutive weeks is a key point for the operability and maintenance of such fields. For arctic regions, operations during ice formation and ice thickness may require an expensive icebreaker vessel. Drifting icebergs also threaten support vessels and production facilities. Sea state for some harsh environment areas may exceed Level 7 during parts of the year, making deployment and recovery of subsea intervention vehicles dangerous. Swimmer can be a tool to operate and or maintain subsea production assets when infrastructure is not reachable from the surface.

SWIMMER CONCEPT

One prime advantage of swimmer is its capability to operate on its own, without a dedicated multiservice vessel (MSV). The AUV part of the hybrid vehicle, the so-called AUV shuttle, ideally is launched from surface production facilities or a vessel of opportunity, and programmed to navigate autonomously to a subsea docking station near the production equipment clusters. Once the Swimmer AUV shuttle is on its docking station, the Swimmer ROV can be remotely controlled from the surface via the field control umbilical. The operator has the hand over of the Swimmer ROV just like for a conventionally MSV-deployed ROV. In this configuration, the Swimmer ROV is powered by the FPSO (or from shore), and intervention is performed conventionally with real time data and video transmission. The Swimmer can remain deployed subsea for several consecutive weeks. Since the Swimmer performs all light IMR operations, the MSV can be dedicated to operations requiring handling of heavy equipment and modules. In this way, Swimmer introduces flexibility into the operations and reduces the overall opex.

The Swimmer concept was invented by Cybernetix in 1997. The feasibility of the concept was demonstrated successfully by Cybernetix and partners (IFREMER, the University of Liverpool) in October 2001 during full-scale sea trials. The Swimmer AUV prototype was programmed to autonomously reach and securely land onto a docking station at 100 m (328 ft) water depth to tap energy and communication for the Swimmer ROV. Following this demonstration, Cybernetix, with Statoil and Total, worked several cases to evaluate the economics of a Swimmer system for various fields. This work to a joint industry project (JIP) among the three partners to further study the technology. Phase 1 of the JIP showed the financial viability for future field developments, and recommended the extension of its scope of work to include pipeline survey and inspection.

In parallel, Cybernetix developed the Swimmer to a level of reliability required by the oil and gas industry. In particular, R&D efforts aimed at a robust and efficient docking algorithm, positioning and navigation systems, and subsea power and data transmissions. More recently, Total and Cybernetix are targeting the development and qualification of a Swimmer system for offshore Angola block 17.

MAIN FEATURES

The Swimmer system is composed of both fixed and mobile assets. The fixed assets are part of the offshore field infrastructures and include the following:

?Subsea docking stations

?Subsea power and data cables embedded into the field control umbilical

Control consoles integrated into the FPSO control room. The hybrid vehicle and the associated IMR tools form the mobile assets and include the following:

?AUV shuttle

?Light Work-ROV equipped with two manipulator arms

?Work-ROV TMS integrated into the AUV shuttle

?ROV tools for light IMR operations.

The Swimmer is designed to stay deployed subsea for up to three months. The current design depth is 1,500 m (4,921 ft) but can be extended to 3,000 m (9,842 ft). The AUV shuttle operating range is 20 km (12 mi) in the standard configuration, but can be extended to 50 km (31 mi), and cruising speed is up to 2 knots. Once docked, the ROV excursion around the docking station is in the 200 m (656 ft) range. The IMR tasks that can be performed by the Swimmer ROV include the following:

1. Valve operation

2. Cleaning

3. Global, close, and detailed visual inspection

4. Wall thickness measurement

5. Cathodic protection measurement

6. Support to electrical diagnosis and trouble shooting /fault finding

7. Assistance to large module replacement

8. Disconnection of lying leads

9. Fluid and thermal leak detection

10. Subsea sampling

11. Replacement of small components

12. Any other ROV operation requiring only the use of manipulators or manipulator carried tools. The Swimmer AUV can be programmed for field survey and pipeline inspection tasks such as the following:

1. Field mapping

2. Pipeline survey

3. Pipeline close visual inspection

4. Pipeline free span detection

5. Pipeline localization

6. Dropped objects detection

7. Cathodic protection measurement.

The hybrid Swimmer vehicle combines ROV-borne IMR capabilities, suitable for maintaining SPS within tether range from the docking stations, with AUV-borne inspection capabilities for survey and inspection of subsea flow lines. Together, the scope of tasks covers the needs for all light IMR operations necessary to maintain a facility in production except replacement of large modules. The tools for IMR tasks on an SPS are generally small and can be embarked directly by the light Work-ROV, or alternatively put into storage compartments onboard the AUV shuttle.

Some tools do not yet satisfy the requirements of the Swimmer system, particularly on long deployments. These include:

· constraints related to the architecture of deepwater developments;

· the higher cost of field pilots.

Upholding its tradition as a deepwater pioneer, Total is the first in the world to address the challenge of polymer-viscosified water flooding, on Dalia (Angola).

Initiated in 2003, three years before the field came onstream, this project illustrates an important aspect of Total's EOR strategy: these technologies are not confined to mature oilfields, but have a role to play in new developments as well.

"Polymer-viscosifiedwaterflooding could raise recovery by 8% over 10 years."

5. Improving Performance on Tomorrow's Mature Fields

Today's specialists already know how to monitor the integrity of infrastructure that is especially exposed to the inherent constraints of the deepwater environment (such as risers, mooring lines and export lines). However, the available data are still too fragmented. Tomorrow's operator at the surface will need to have available a comprehensive vision of the subsea infrastructure and the capacity to intervene promptly if something goes wrong. With both of these goals in mind, Total teamed up with the French robotics engineering firm Cybernetix to develop an innovative IMR system.

The new concept is called SWIMMER (for Subsea Works Inspection and Maintenance with Minimum Environment ROV). It is based on an Autonomous Underwater Vehicle (AUV) which contains its own Remotely-Operated Vehicle (ROV), and is designed to spend up to three months on the sea floor. The AUV is programmed onboard the FPSO then "swims" under its own power to one of the docking stations installed at the bottom of the ocean. After it docks, it releases its ROV. The ROV itself is controlled by an operator at the surface, and can intervene anywhere within a 200-meter radius around the station.

SWIMMER embodies some key advances:

· in terms of responsiveness: uninterrupted presence on the seabed by the AUV for a period of three months improves surveillance of the installations and allows quicker intervention if necessary;

· in terms of economics: because it does not depend on a dedicated support vessel, the AUV can translate to a substantial reduction in operating costs.

Work is already under way to develop second-generation SWIMMER and subsea communications systems to increase its range and applications.

· It would improve the safety of operations by limiting diver intervention and therefore the risk of accidents;

· It would limit inspection time, since an ROV can operate for longer periods than a human diver, even in rough seas.

After evaluating the potential solutions, R&D opted in favor of a Crawler/HERO ROV developed by ECA and operated by DCNS. Compared with a conventional ROV, the Crawler/HERO robot is equipped with thrusters that enable it to "stick" directly on the surface of the FPSO hull. Total's R&D qualified this innovative solution in 2011. It is destined to be tested on one of Total's FPSO vessels in the future.

The analyses carried out by the Group's drilling experts indicated that complying with Total's safety standards would have averted that uncontrolled well blowout, which led to the explosion of a drilling rig. Although the probability of occurrence of this type of accident is low, Total has taken every measure to further enhance the safety of its drilling operations and learn the valuable lessons of this event. offshore environment intervention drilling

· continuous measurement of a set of physical characteristics of the water, seafloor and upper layer of subsea sediments. Measurements are performed using chemical sensors, a detector of gas bubbles escaping from the seafloor and various other types of probes (such as pressure, microseismicity and ground motion sensors);

· real-time analysis of the data gathered;

· semi-automatic triggering of warnings in the event of danger for personnel or facilities.

HORUS is a major breakthrough that brings within grasp a real-time knowledge of changes in the key parameters of the subsea environment over the various phases of a field's life. This innovation is essential, given that alterations in pressure and temperature conditions, or vibrations generated by production operations, can sometimes cause soil instability. HORUS is a significant contributor to the safety of deepwater developments, and will soon be tested on one of Total's production sites.

Offshore Areas There has been a g r e a t deal of e f f o r t devoted to assessing the petroleum p o t e n t i a l of the c o n t i n e n t a l margins of the U.S. and the world. One of the more recent works is contained inMemoir 15 which was published by the 'American Association of Petroleum Geologists i n 1971 under the sponsorship of t h e N a t i o n a l Petroleum Council.

The c o n t i n e n t a l margins of the U.S., which include submerged lands from the s h o r e l i n e o u t to a water depth of 2500 meters, c o n s t i t u t e s an area of about 890,000,000 acres (1.4 m i l l i o n square miles). A s s t a t e d i n Memoir 15, some of t h i s area is known t o be non-prospective, although the report does not speculate on the s i z e of these non-prospective areas. Of the t o t a l 890,000,000 acres approximately 560,000,000 acres (63%) l i e on the c o n t i n e n t a l s h e l f (shorel i n e out to 200 m e t e r s ) . F i g u r e 49 d e p i c t s the t o t a l acreage and broadly how it is d i s t r i b u t e d . 421,000,000 acres (47%) l i e adjacent to the conterminous U .S .and the South Coast of Alaska. The remaining 469,000,000 acres (53%) a r e located north of the Alaskan peninsula. Also shown i s the amount of OCS and S t a t e acreage under lease compared t o the 239,000,000 acres located on the cont i n e n t a l s h e l f of the conterminous U.S. and the South Alaska coast. The approximate 5.0 m i l l i o n acres under l e a s e r e p r e s e n t about 2.0% of t h i s s h e l f area and about 112 of 1.0% of the t o t a l a r e a .