Greenfield recovery solutions 

Subsea processing technologies can be a decisive factor when assessing viability of complex greenfield developments. To date, when applied to a greenfield development, the technology has been enabling.  In other words, without subsea processing, the field would not otherwise be economic to exploit.  Low, natural production rates result in sub-par return on investment (ROI) and delayed payback versus competing projects. In many cases the reduced revenue rate over the life of field means that the projects' present value and estimated ultimate recovery can look weak versus other projects.  

Subsea processing can help achieve faster payback, accelerate production and result in improved ultimate recovery thereby taking some projects from below average producers to world class producers. Additionally, development CAPEX can be reduced through the avoidance of applying alternative costly solutions like flow assurance mitigation. 

• Enabling projects that would otherwise not meet project hurdle rates 
• Upgrading  individual project metrics to better compete in the internal market for capital
• Upgrading overall project portfolio with a higher proportion of higher quality projects

Subsea processing has enabled the development of complex reservoirs in difficult subsea environments including:

• Under pressured subsea reservoirs. These reservoirs may lack the energy to produce to the surface in economic rates or volumes
• Heavy oil and/or low permeability subsea reservoirs. Available reservoir energy is insufficient to transport the fluids through the reservoir, wells and flowlines
• Tiebacks. Produced fluids have to overcome the pressure drop associated with being transported over long distances. Typical scenarios include a satellite tieback to a long distance host, or transport directly to beach. These scenarios may be considered for developing large, remote gas fields or fields in the arctic 

Subsea boosting, subsea separation and pumping, and gas compression allow energy to be added to the produced fluids. This increases production and reserves by reducing the backpressure on wells and reservoirs.  Separation allows efficient energy management as well as increased flow assurance benefits.  These benefits are realized when the field begins operation, not just later in field life.

In greenfields, gas-liquid separation is commonly applied in conjunction with boosting as a technique to recover difficult-to-produce oil.  In deep water fields, this combined solution enables higher efficiency pumping, minimizes flow assurance risks, and diminishes tieback limitations. It’s also effective in enabling the production of complex reservoirs containing heavy, viscous oil and low pressures. This approach has been successfully applied in

As subsea processing technologies advance, it is becoming possible to eliminate the need for surface platforms. Today, subsea gas compression can be used to condition and compress the gas for transport to shore. Additionally, tiebacks to remote hosts can be made over increasing distances.  In the future, it may be possible to move more complicated functionality that is currently undertaken by surface platforms to subsea.

FMC Technologies is leading the development of technologies to enable such a future.  FMC is successfully enabling the decommissioning of existing surface facilities for Brownfield applications.

Subsea processing addresses many potential operational or flow assurance challenges for deepwater subsea projects.  Subsea processing solutions can reduce the related capital costs of providing flow assurance prevention or mitigation.  And, at the same time, it can increase production and reserves recovery. 

Subsea processing can provide an alternative to:

• Topsides architecture - Subsea processing potentially eliminates entire surface platforms. Subsea-to-beach developments are now possible for gas fields with subsea gas compression. For arctic developments, subsea separation and pumping can enable transport to a very remote hub for further processing.
• Subsea architecture - Subsea processing enables more possibilities. More options are now possible including a low pressure subsea hub with subsea separation and pumping.
• In-well ESPs - Subsea processing offers more reliable options for adding energy. In-well ESPs have potentially low reliability and high intervention costs.  Other options including mudline boosting and the combined solution of subsea separation and pumping can potentially add energy more effectively.
• Gas lift - Subsea processing widens the application for gas lift. Gas lift system designs are influenced by gas lift volume and gas lift pressure.  In applications where there are high gas fractions or long step-outs, pressure drops are increased. In addition to pressure drops, surface gas compressor capacity can pose another limitation. The addition of mudline boosting or the combined solution of subsea separation and pumping can potentially add energy more effectively.
• Water injection - Subsea processing widens applications for injection techniques. Water injection capabilities are usually preinstalled topsides, often ahead of knowing whether an aquifer is present or not. Subsea water injection of produced water or raw seawater using subsea pumps can take weight and space off the topsides facility and provide an option to retrofit once the presence of aquifer drive is confirmed.  This can eliminate the need for high pressure risers for water injection using topside facilities.