Page 27: of Offshore Engineer Magazine (Mar/Apr 2013)

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Production from subsea wells is For brownfelds, increased oil

Increased oil recovery growing in importance in many recovery (IOR) can be critical

Brownfelds techniques serve operator portfolios. As easily to keep the feld operating

P as enhancers for accessible oil is depleted, subsea economically despite depleting processing offers a compelling reservoir energy and increasing maximizing production solution to economically produce in water cut. from brownfelds a variety of challenging conditions.

Worldwide, there are more than Enabling technologies and enablers to 4000 subsea wells onstream today To improve recovery rates, operators improve the economic and FMC projects that this number often turn to IOR techniques. These viability of greenfeld will grow to nearly 7000 by 2017. are typically deployed during,

In fact, analysts expect the number or after, primary depletion and developments. of subsea wells coming onstream can be considered basic reservoir

Chris Shaw of between 2013 and 2017 to increase management techniques to improve

FMC Technologies by 68% over the previous fve-year sweep and accelerate production period. from the reservoir. These techniques examines the issues.

For operators, extracting as often include: much of the original oil-in-place as l Adding reservoir drive energy via possible is critical. water or gas injection.

While conventional oilfelds l Modifying water injection report typical recovery rates chemistry to reduce interfacial between 30-60%, subsea wells tension and rock wettability to often fall below that mark, reporting reduce residual oil saturation (EOR recovery rates less than 40%. Just technique).

a 1% increase in subsea recovery l Removing back pressure via can deliver an additional 10mmbo boosting or artifcial lift.

of production from a typical large l Workover, stimulation or re-entry feld. This additional production of existing wells to improve infow can dramatically affect project and/or access new targets.

economics, improving the viability l Creating more penetration points of greenfeld projects or ensuring to access bypassed areas of the that brownfeld installations reservoir. continue operating proftably. These techniques can each For greenfeld applications increase recovery by 3-10% of such as long distance step-outs original oil-in-place and can extend in deepwater, in the Arctic or a feld’s productive life by several challenging reservoirs with low- years or decades. energy or heavy oil, the increased To achieve these results, a number production rates and recovery can of technologies are required: be moving forward. The Arctic l Subsea pumping and subsea holds more than 90 billion bbl of separation are used to reduce back undiscovered oil. pressure in subsea oilfelds. >

The recovery challenge. Global subsea wells onstream.

oedigital.com March 2013 | OE 29 oe_BrownfieldFMC_rev2.indd 29 27/02/2013 11:27