The oil and gas industry continues to reach further into increasingly complex reserves in ever-more challenging environments, and the surge in the number of subsea operations is making tougher demands on technology developers. The importance of intelligent technology in bringing efficiency to these complex operations is growing every day.
One does not have to look far to see that investment in subsea operations is booming. Market intelligence firm ODS-Petrodata reports that 107 subsea projects are already in place this year, and almost 100 are scheduled for the next. The Gulf of Mexico, Northwest Europe, Latin America and West Africa will see much of this development, posing technical and commercial challenges to exploration and production efforts.
Intelligent well design is an important weapon in overcoming these challenges, and the industry is looking to incorporate 'smart' features into many components in the offshore production infrastructure to improve efficiency and enhance remote control capability. Fields such as Champion West in the South China Sea, the first developed by Shell as a 'smart field' project, are the proving grounds for new technology and map out the key industry goals of making complex reservoirs, previously thought to be too expensive to exploit, into commercial realities.
Improving valve technology is a prime goal, and exploration and production companies increasingly recognise that the use of intelligent control systems for valve trees is becoming a competitive advantage, and a defining factor of intelligent well development. Development efforts by the likes of BP are working towards all-electric subsea production control systems to replace industry standard electro-hydraulic control systems, with the aim of making them more reliable, more responsive and more cost effective.
The current standard technology is prone to disruption – in part due to the effects of increased depth – and in high-pressure environments the technology is often operating at its limit. More reliable technology and greater ability to use surface-operated valves to control flows, isolate reservoir zones, and improve ratio of water production to hydrocarbon recovery, is in great demand.
At Champion West the remote, electronic activation of well valves is one of the vital components in the smart infrastructure that enables Shell to address any flow problems in a timely manner to improve overall well management. The industry as a whole is now investing in valve technology with embedded processor and networking capability to work alongside sophisticated monitoring technology coordinated through a central control station, particularly in operations with long tiebacks.
The implementation of smart control valves has a track record of improving efficiency and boosting revenue. Two years ago Unocal, now part of Chevron, installed intelligent pump and valve systems to boost the efficiency of its Monopod platform in the Cook Inlet Basin, Alaska.
Having been installed over 40 years ago the platform presented many challenges to efficient production, mostly from the high gas-lift usage rates. Too much gas was needed to produce too little oil. Previously, the flow of lift gas was not subject to active control, but the development team perceived an opportunity to stabilise flows using smart control valve technology.
Soon after implementation clear benefits emerged in terms of increased revenues, as well as improved operating costs compared to conventional valve technology, with profitability projections quickly boosted by 12%.
Since then there have been many other applications of intelligent well technology. This year, for instance, WellDynamics deployed its Smartwell completion technology in Nigeria's Agbami field for Star Deep Water Petroleum.
The field development, which consists of 20 oil-producing wells, 12 water-injecting wells and six gas-injecting wells, which will have flow control and enhanced monitoring systems.
The technology includes WellDynamics's Direct Hydraulics and Accu-Pulse downhole control system, plus its multi-position HVC interval control valve (HCV-ICV) with customised flow trim. HCV-ICV is a remotely operated, downhole valve designed for applications requiring selective control flow, and is suited to the kind of high-pressure / high-temperature (HPHT) environments with which the industry is now confronted.
For technology developers the goal has been to link control valves to an extended data network, coordinating control valve operation with the increasingly detailed data available on flow rates and operating conditions. Connecting valves to a network allows distributed control, which can enable operators to reconfigure piping and networking systems so that a field can continue producing even if there is a blockage in, or damage to, the pipeline network.
Similarly, there has been a focus on producing valves that consume less power, not only for the sake of energy efficiency but also to create systems that can be deployed in applications where conventional valves cannot be used due to the lack of suitable power sources.
SMART VALVE DEVELOPMENT
Marotta, with its intelligent fluid control proposition, is among those developers that have made significant advances in the integration of digital controller software algorithms and valve systems to enable them to react autonomously or execute commands from a remote host. In developing these solutions the company has not only found that smart valves can improve flow control, but also that in the context of improved data on cycles of operation and degradation the technology can enable
preventative maintenance and early warn of impending failure, which has a further positive impact on long-term operating costs.
Another manufacturer leading the way in smart valve development is Emerson Process Management, which is seen its Fisher range of valves used in key energy infrastructure developments such as the Qatar LNG plant.
The range of high-performance Fisher digital valves enabled the implementation of customised valve designs to cope with the pressure, flow capacity and temperature demands of the world's first twin-mega-train LNG plant.
All valves were equipped with FieldVue digital valve controllers, which incorporated a sophisticated diagnostic capability.
The successful operation of smart control valves in diverse applications, from complex offshore developments with long subsea tiebacks to major LNG plants, has quickly given them a good track record for delivering efficiency gains, and the future of the technology will be dominated by greater investment in research and development to achieve optimised valve control in harsh operating environments.
As with previous implementations, valve solutions will no doubt be custom built to meet the specific needs of offshore applications, but the overall trend will be to improve the integration of valve control with well data flows, and to make their response more accurate and more precisely adjustable.
Technology developers have done much to push forward the capability of smart valves, but the tests to which the E&P industry will put the technology in the field will determine how fast such systems will need to mature.