Anchois 1- Oil&Gas Field

1 OFF550 SUBSEA TECHNOLOGY Project Report / ANCHOIS – 1 Field

! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!By!Jose!V.Taboada!//!Stud.nr:!217961!!

Project Overview

The “Anchois – 1” is part of the Production Tanger-Larache blocks (47, 48, and 49 in Offshore Morocco), the overall of the area is around 2744 m2, being located at 40Km off the Morocco shoreline to South West (SW). The project operator is lead by Repsol YPF SA (36%), and operated the consortium with:

Gas Natural Exploration SL→ 24% Dana Petroleum (D&P) LTD→ 15% ONHYM→ 25%

The “Anchois – 1” includes encountering reservoir with 90 m of Gross Gas Column in Two sections (100Bcf = 2.8Bcm =2.779MMSm3). Potential restriction with “Gas-Bearing Sands” detected. The “Anchois – 1” reservoir is a discovery from March 2009. The Field Development contains a Subsea, Offshore Flowline and Pigging Line infrastructure. The concept selection carry out is a Subsea System tied back and exported to Onshore Plant (“Subsea Wells Tie-back to Onshore Plant”) via flow lines and control umbilical.

The field itself shall be designed with flexibility for new tie-in of the new discoveries further in the area. Prospection phase has been development in 2009, and Exploration was during 2011 and the Drilling phase along 2013.

The water depth is around 387m.The field representation and existing subsea infrastructure, shown on the Annexes.

Subsea Concept

First at all, to reach up a determination of a Subsea Concept, to carry out and be implement, shall be base on the ‘‘Objectives of the Design’’, are listed below:

! Efficient Interface coordination (between Drilling &Well, Subsurface, Downstream Facilities).

! Cover all design premises for the facilities concept development process, and successive development steps.

! Have into account, future operational objectives and functional requirements for field.

! Establish coalition between services companies and operator.

In based on previous objectives cited above, the Concept selected shall be a “Subsea Wells Tie-back to Onshore Plant” through “Subsea Wells + Multi-Manifold”.(See Annexes representation).

Which one, has been determined through a survey of couple number of parameters and requirements to satisfy. As main requirement of the concept, shall allow for tie-in of the future prospects in the area, for more Subsea Templates, in addition to possible future Low-pressure production. Which one, we concept selected allows that. In terms of production rate, using Multi-Manifold (with Gas Condensate Pumps) will increase considerable high, due to two pumps in parallel position integrated.

(QOutLetFlow=QA+ QB → ↑"$ ↑), this particular dimensioning allows to decrease the pressure rate at the outlet in the Multi-Manifold (HOutLetFlow=HA- HB → POutLetFlow↓↓). See next representation below;

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Figure 1. Pumps production system into the Multi-Manifold.

In contrast, using this type of dimensioning is going to demand more consuming Energy Supply.

Sand detectors and Gas meters will be installed at the Wellhead on each well. Such as, Salt detection will be installed as part of the wet gas meters.

The objective of this subsea solution is to keep up affordable to a manageable level of activity within a reasonable time frame, and balancing the full lifecycle with the benefits of production from the field.

Subsea Features and Key Equipment

The whole Subsea installation begins from Subsea satellite wells, to ending of the Flow lines and Cables to Onshore plant. The key pieces equipment, could the two VXTree for each well, have the next characteristic bellow;

• Simple installation from Vessel, as result a decrease of Cost Installation.

• Save Energy Supply, only is needed one time to run each BOP from shore.

As second key part of the installation, could be the Mult- Manifold (with Gas Condensate Pumps), being classified as key element for the whole installation, for the next reason below;

• Allows flexibility for new tie-in of the new discoveries further in the area (new Infield Flow lines into the same Multi-Manifold).

• Rise up the caudal Flow production, from each column of Gas, due to two pumps, as having also safety effect to avoid the formation of ‘Gas Hydrates’, where the pumps will draw down wellhead pressure and increase considerably the Flow line Inlet pressure and the caudal Flow from wells increase as well. (VFlow↑→ Ta↑↑ and Pressure↓).



• A considerable reduction of the CAPEX, due to a minor controls requirements and the installation Cost, in contrast the Net increases in Oil production (QFlow↑= $↑↑).

Therefore, using a Multi-Manifold will increase the Control Capacity, Flexibility, Reservoir Management and Production.

As third key component, shall be cited the Subsea Control Module, which one shall be capable of management and controlling each VX-Tree with associated sensors, valves, and flow control system, in addition to downhole applications.

Other Options and Solutions

We could carry out two main types of subsea solutions;

1. Deepwater Platform to Onshore Plan (“Offshore stand-alone development”).

2. “Subsea Wells Tie-back to Onshore Plant” through “Template”.

For the first one, the impact of this conceptual development has high cost of implementation for Facilities Offshore, which ones will increase the Cost of Production phase, that means shall raise considerable the Reduced Costs during cited phase, as result that Equipment is not designed for the entire project life, having interchangeable phases. In the second one, to consider this conceptual idea, could be carry out and satisfactory to implement for this Well-Stream Composition in particular. The Template is a large steel structure which is used as a base of a global integration for wells, subsea trees and manifolds.

This subsea well configuration has better global integration of the subsea equipment and productive structures covering, to prevent damage from fishing activities. But breaks down the further concept develop in the area (“Flexibility for new tie-in of the new discoveries”).

Optimal Solution

As was stated above, the solution to execute might be a “Subsea Wells Tie-back to Onshore Plant” through “Subsea Wells + Multi-Manifold”.

Knowing that reservoir is close to shore and located between shallow to transitional waters (D=387m), due to using this concept selection will contribute to avoid the huge cost of displacement a Platform dry/wet wells and FSU or even high Risk levels during the Production(“Offshore stand-alone development”).

By other hand, according to the estimates reserves provided (100Bcf = 2.8Bcm =2.779MMSm3=16.479MM BOE) consider this Input information given, could be classified as big field, that means, installing of this concept selection (“Subsea Wells Tie-back to Onshore Plant”) will contribute for a long period of life cycle Production, reducing costs during the Production phase.

From OPEX perspective, exist less leak possibilities, less risk of mal-operations, and simplified operational procedures.

Although, having into account the needs of the Field itself (Big reservoir + Two columns of gas), the most optimal philosophy design to carry out (“Subsea Wells + Multi-Manifold”) for this Well-Stream Composition, looking to keep open new possibilities for new subsea wells located around further, that means using Multi-Manifold (with Gas Condensate Pumps) is going to allow us, more Infield Flowlines into the same Multi- Manifold, as well was explained previously.

The magnitude of Pipeline Export system (L=40Km) will have a better contribution during the production phase for this solution, rather than “Offshore stand-alone development” solution, which one is suitable for small fields.

In summary, the Facilities (Risers, Export Pipeline rises, Subsea System, Topside Production Facilities or Mooring lines) will be avoided to install and mobilize that Equipment.

A balance between Economical, Technical and Strategic issues had been found for an optimal solution.

Risk and Lessons Learned

Focus on the “Offshore stand-alone development”, in case to implement this concept development, is going to originate more Risk Levels during the Production Phase, due to is necessary to mobilized and implement more Equipment Supply Offshore, rather than the concept determined above.(“Subsea Wells Tie-back to Onshore Plant”).

For the Optimal solution, the formation of Span and Buckling along 40Km of pipeline to shore, are quite likely to happen these types of Risk, as consequence of the conditions and properties (Sand = Soft Friction) on Seabed, as well as high dimensioning requirement for the legs/foundations of the Multi-Manifold. Such as, a Corrosion distribution along the pipeline, shall be expected to happen.

As main Risk of Flow Assurance, obviously is the Gas-Bearing Sand formation that might be gives the chance to originated Slugg Effect, or even sand screen failure. The mitigation of this harms, shall be prevent through as first barrier, a Sand Control System (Active Sand Control is needed!), and with second barrier on the Terminal Plant (Onshore), through Slugg Catchers.

From the Economical perspective, the installation along pipeline to shore (40Km) will rise up the CAPEX investment, and also reduced the controls requirements and given more flexibility.

As Risk induced by the Owner (Repsol YPF) might not be willing to invest enough money for O&M while Wells were producing profitably.

Concerning to the Environmental Risk, the Concept selected as Optimal, will have a major impact on the Sea bottom nature or even a limitation area for fishing activities.



References

[1]http://www.onhym.com/Default.aspx?alias=www.onhym.com/EN

[2]Leslie Adriaansen, Jens Henrik Neuenkirchen, Jim Cattanach, Sigurd Moe, Carl Eriksen and Huge Clayton. Subsea Control and Data Acquisition. Professional Engineering Publishing(June -2002).

[3]API RP 17A, Recommended Pratice 17A, Design and Operation of Subsea Production Systems.Second Edition(Sept – 1996).

[4]http://www.repsol.com/es_en/corporacion/prensa/notas-de-prensa/ultimas- notas/descubrimiento_gas_aguas_marruecos.aspx

[5]http://www.tekna.no/ikbViewer/Content/22993/Nils%252520Arne%25252 0S%2525C3%2525B8lvik.pdf

[6] http://www.subseaworld.com/fields/dana-petroleum-makes-gas-discovery- offshore-marocco-02913.html

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OFF550 SUBSEA TECHNOLOGY ANNEXES Project Report /ANCHOIS – 1 Field

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OFF550 SUBSEA TECHNOLOGY ANNEXES Project Report /ANCHOIS – 1 Field

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! By!Jose!V.!Taboada!//!Stud.nr:!217961! !! !

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! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!Ref:!ONYM(www.onhym.com).Ac5vity!Report!2009.Office!Na5onal!Des!Hydrocarbures!et!des!mines.!Kingdom!of!Morocco.!2009.!

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OFF550%SUBSEA%TECHNOLOGY%%%2%By%Jose%V.Tabaoda_St.nr:%217961%2%%%%%%%%%%%%%%%Project%Report%/ANCHOIS%–%1%Field%!

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! !Ref:!ONYM(www.onhym.com).Ac5vity!Report!2009.Office!Na5onal!Des!Hydrocarbures!et!des!mines.!Kingdom!of!Morocco.!2009.!

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Annexes!

NGL!Compressor!Sta5on!

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!!OFF550%SUBSEA%TECHNOLOGY%%%2%By%Jose%V.Tabaoda_St.nr:%217961%2%%%%%%%%%%%%%%%

Project%Report%/ANCHOIS%–%1%Field%!!!  Project(Overview(

N  Objec.ve:(To!transport!Rich!Gas!from!Blocks!(47,!48,!and!49)!to!Onshore!Plant!Facili5es.!

N  Field(Development:(Subsea!+!Offshore!Flowline!+!Pigging!Line.(“Subsea'to'Shore'–'S2S”)!

N  Concept(Selected:!“Subsea!Wells!TieNback!to!Onshore!Plant”!through!“Subsea!Wells!+!Mul5NManifold”.!!

N  Drive(Mechanism:!Rich!Gas!+!Condensate!shall!be!Recovered!by!Deple2on!and!later!by!Gas'Compression.!

N  Loca.on(:(From!“Anchois!1”!wells!to!the!Onshore!Facili5es!at!40Km!off!the!Morocco!shoreline!to!South!West(SW).!

N  Owner:(Repsol!YPF!(36%)!N  Shareholders(:(Gas!Natural!Explora5on!SL!(24%),!

Dana!Petroleum!(D&P)!LTD!(15%)!and!ONHYM!(25%).!

N  Capacity:!100Bcf!=!2.8Bcm!=2.779MMSm3(High!Volume!of!Rich!Gas!moved).!

N  Target!Depth!(TD)!Points!for!each!Column!of!Gas,!are!depth.!!(Greater!Depth!Reservoir!=!High!Pressure)!!

!  Schedule(&(Phases(

N  Prospec.on:(during!2009!(Discovery!in!March!2009).!

N  Explora.on:(during!2011.!N  Drilling:(during!2013.!N  Produc.on:(Forward!2014.!

!  Challenges(N!!!!!!Flow!Assurances.!

N  Well!Stream!Composi5on.!

N  Remote!Control.!

N  Corrosion!Control!&!Corrosion!Monitoring.!

N  GasNBearing!Sand!forma5on.(demanded%acousSc%%%Sand%Control).!

N  Gas!Hydrates!forma5on.(avoid%through%MEG'flow%control).!

N  Pipelines!Rou5ng.(Against!Wave!Impact!&!Abrasion!from!moving!Sand!and!Gravel).!

!  Design(Objec.ves(

N  Be!available!to!produce!as!much!as!possible!from!Reservoir.[QOutLetFlow!=↑$!↑!]/Max(Produc.vity!/!

N  LowNCost!Pumping!for!both!Gas!Wells!to!recovery!more!Gas./Minimize(Energy(Consump.on/!

N  The!whole!system!must!be!FailESafe.!N  Marine!Systems/Subsea!Technology!for!Improved(

Operability(and!CAPEX/OPEX(Op.miza.on.!N  Reservoir!Proper5es!on!a!wide!range!of!Inlet!

composi5ons.!(Flow(Assurance)!N  Environmental(Impact!Considera5ons.(HSE)!

Anchois 1- Oil&Gas Field

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