Concrete Breakwater for the Greater Tortue Ahmeyim Project for BP in Mauritania and Senegal

2021 ◽  
Author(s):  
Alexis Replumaz ◽  
Yann Julien ◽  
Damien Bellengier
Keyword(s):  
Water Depth ◽  
Environmental Benefits ◽  
Direct Access ◽  
Road Transportation ◽  
Reclaimed Land ◽  
Gas Field ◽  
Execution Plan ◽  
Field Development ◽  
Port Area ◽  
Historical Presence

Objectives / Scope During summer 2017, EIFFAGE GENIE CIVIL MARINE was invited by BP to bid for the construction of a concrete caisson breakwater protecting an offshore LNG liquefaction floating terminal which will be located 10 km west from Saint Louis, at 33 m water depth on the Mauritanian / Senegalese maritime border. Methods, Procedures, Process The basic design as originally proposed by BP was composed of 18 rectangular concrete caissons laying on an underwater rumble-mound foundation. Dimensions of the concrete boxes were approximatively 63,5 meters long, 32 meters wide and 30 meters high, on a design consisting of multi rectangular cells (128 units/caisson) EIFFAGE GENIE CIVIL MARINE answered to the ITB by proposing under an EPC basis an alternate caisson shape optimizing drastically the concrete quantities. Results, Observations, Conclusions Alternate caisson dimensions were 54,5 m long, 28 m width, 35m height including a 3 m high crest wall at the top against extreme waves overtopping. The geometry of the caisson has been changed to a 10 lobes caisson. The weight of each caisson is around 16 000 tons. As a result of the subsequent FEED studies performed from April 2018 to February 2019, including 3D model testing in basin, Eiffage was able to reduce the amount of concrete required by 40 % compared to the first design, leading to 124 200 cum of concrete and both financial as well as environmental benefits. Novel/Additive Information Execution plan involving Mauritania and Senegal This infrastructure offers key local content components for this gas field development in each country, something Eiffage had key experience with thanks to an historical presence in the the region : Eiffage started its activities in Senegal more than 100 years ago. The original execution plan as proposed by Eiffage for the EPC phase signed in February 2019 was to build the 21 concrete caissons in Dakar -Senegal. A dedicated yard of 15 hectares has been reclaimed besides the actual port of Dakar providing a safe direct access to the sea and the required water depth for the caissons towing. As a result, at peak more than 600 jobs will be created in Senegal, with the reclaimed land for the fabrication yard left as a legacy for the port area. The underwater rumble mound requires 2 million tons of quarry material. EIFFAGE's proposal was to produce, transport and load from Mauritania those materials. A specific logistics scheme between the quarry and vessels loading point has been developed including a bypass road around Nouakchott. The transport of the quarry materials requires the mobilization of 170 trucks. A special safety mitigation plan including dedicated training is being implemented in order to reduce identified risks linked to road transportation.

Optimization Applied to Buzios Flexible Riser Systems and Subsea Layout

2021 ◽  
Author(s):  
Vinicius Gasparetto ◽  
Thierry Hernalsteens ◽  
Joao Francisco Fleck Heck Britto ◽  
Joab Flavio Araujo Leao ◽  
Thiago Duarte Fonseca Dos Santos ◽  
...  
Keyword(s):  
Deep Water ◽  
Technology Use ◽  
Capital Expenditure ◽  
Lessons Learned ◽  
Internal Diameter ◽  
Flexible Riser ◽  
Flexible Pipe ◽  
Injection Wells ◽  
Gas Field ◽  
Field Development

Abstract Buzios is a super-giant ultra-deep-water pre-salt oil and gas field located in the Santos Basin off Brazil's Southeastern coast. There are four production systems already installed in the field. Designed to use flexible pipes to tie back the production and injection wells to the FPSOs (Floating Production Storage and Offloading), these systems have taken advantage from several lessons learned in the previous projects installed by Petrobras in Santos Basin pre-salt areas since 2010. This knowledge, combined with advances in flexible pipe technology, use of long-term contracts and early engagement with suppliers, made it possible to optimize the field development, minimizing the risks and reducing the capital expenditure (CAPEX) initially planned. This paper presents the first four Buzios subsea system developments, highlighting some of the technological achievements applied in the field, as the first wide application of 8" Internal Diameter (ID) flexible production pipes for ultra-deep water, leading to faster ramp-ups and higher production flowrates. It describes how the supply chain strategy provided flexibility to cover the remaining project uncertainties, and reports the optimizations carried out in flexible riser systems and subsea layouts. The flexible risers, usually installed in lazy wave configurations at such water depths, were optimized reducing the total buoyancy necessary. For water injection and service lines, the buoyancy modules were completely removed, and thus the lines were installed in a free-hanging configuration. Riser configuration optimizations promoted a drop of around 25% on total riser CAPEX and allowed the riser anchor position to be placed closer to the floating production unit, promoting opportunities for reducing the subsea tieback lengths. Standardization of pipe specifications and the riser configurations allowed the projects to exchange the lines, increasing flexibility and avoiding riser interference in a scenario with multiple suppliers. Furthermore, Buzios was the first ultra-deep-water project to install a flexible line, riser, and flowline, with fully Controlled Annulus Solution (CAS). This system, developed by TechnipFMC, allows pipe integrity management from the topside, which reduces subsea inspections. As an outcome of the technological improvements and the optimizations applied to the Buzios subsea system, a vast reduction in subsea CAPEX it was achieved, with a swift production ramp-up.

Study on the Characteristics of Well Completion Technology in Deepwater Oil and Gas Field Development

2021 ◽  
Vol 3 (8) ◽  
pp. 70-72
Author(s):  
Jianbo Hu ◽  
◽  
Yifeng Di ◽  
Qisheng Tang ◽  
Ren Wen ◽  
...  
Keyword(s):  
Deep Water ◽  
Deep Sea ◽  
Oil And Gas ◽  
Gas Field ◽  
Marine Research ◽  
Field Development ◽  
Research Technology ◽  
Well Completion ◽  
Development Capacity ◽  
Exploration And Development

In recent years, China has made certain achievements in shallow sea petroleum geological exploration and development, but the exploration of deep water areas is still in the initial stage, and the water depth in the South China Sea is generally 500 to 2000 meters, which is a deep water operation area. Although China has made some progress in the field of deep-water development of petroleum technology research, but compared with the international advanced countries in marine science and technology, there is a large gap, in the international competition is at a disadvantage, marine research technology and equipment is relatively backward, deep-sea resources exploration and development capacity is insufficient, high-end technology to foreign dependence. In order to better develop China's deep-sea oil and gas resources, it is necessary to strengthen the development of drilling and completion technology in the oil industry drilling engineering. This paper briefly describes the research overview, technical difficulties, design principles and main contents of the completion technology in deepwater drilling and completion engineering. It is expected to have some significance for the development of deepwater oil and gas fields in China.

Offshore Gas Field Development Strategy and Flow Assurance Prediction and Optimization in Harsh Environment

2018 ◽  
Author(s):  
Humoud Almohammad ◽  
Abdullah Al-Derbass ◽  
Abdulaziz Alsubaie ◽  
Mohammed Bumajdad ◽  
Abdulaziz Al-Khamis ◽  
...  
Keyword(s):  
Development Strategy ◽  
Harsh Environment ◽  
Flow Assurance ◽  
Gas Field ◽  
Field Development

Greater Plutonio Riser Tower Installation: Studies and Lessons Learnt

2009 ◽  
Author(s):  
Charles-Alexandre Zimmermann ◽  
Guilhem Layrisse ◽  
Daniel de la Cruz ◽  
Jeremy Gordonnat
Keyword(s):  
Water Depth ◽  
Bending Moment ◽  
Lessons Learned ◽  
Field Development ◽  
System A ◽  
Analysis Methodology ◽  
Lessons Learnt ◽  
Future Improvement ◽  
Tower System

The BP operated Greater Plutonio field development offshore Angola comprises a spread-moored FPSO in 1,300 m water depth, serving as a hub processing the fluids produced from or injected into the subsea wells. The selected riser system is a Hybrid Riser Tower comprising 11 risers bundled around a central structural tubular (Core Pipe), tensioned by a steel Buoyancy Tank at its top and maintained by an anchor base at its bottom. The Riser Tower is fabricated onshore and then towed to the field for final installation in deepwater near the FPSO. Once the Riser Tower installation is completed the risers are connected to the FPSO by means of flexible jumpers and to the flowlines by means of rigid spools. All fabrication and installation work has been performed by Acergy. This paper presents the studies performed to cover all the steps of the installation phase: build-up of the Orcaflex model, miscellaneous studies to determine model and analyses parameters, towing analysis, upending analysis, Buoyancy Tank ballasting and deballasting analyses, and contingency analyses. This paper is mainly focused on the Riser Tower installation but also covers the installation of the Riser Tower anchor and of the flexible jumpers in order to give a complete overview of the operations related to the Riser Tower system. A comparison between computed data and data measured during operations is also presented to support the overall installation analysis methodology. Lessons learned are provided for future improvement of Riser Tower installation covering main challenges such as Riser Tower modeling, weight/buoyancy repartition along the Riser Tower, Buoyancy Tank ballasting adjustment in Lobito bay, fatigue issues during surface and subsurface tow, bending moment issues during upending, etc.

Marginal Gas Field Development through Innovative Sand Control Completion Concept

2016 ◽  
Author(s):  
M. Zamberi ◽  
M. Mohd Sallehud-Din ◽  
S. Shaffee ◽  
N. Nik Kamaruddin ◽  
M. B. Jadid ◽  
...  
Keyword(s):  
Gas Field ◽  
Field Development ◽  
Sand Control

The Clipper Field, Blocks 48/19a, 48/19c, UK North Sea

2003 ◽  
Vol 20 (1) ◽  
pp. 691-698
Author(s):  
M. J. Sarginson
Keyword(s):  
North Sea ◽  
Upper Permian ◽  
Lower Permian ◽  
Reservoir Properties ◽  
Gas Field ◽  
Field Development ◽  
Matrix Permeability ◽  
Recoverable Reserves ◽  
Reservoir Permeability ◽  
Sandstone Formation

AbstractThe Clipper Gas Field is a moderate-sized faulted anticlinal trap located in Blocks 48/19a, 48/19c and 48/20a within the Sole Pit area of the southern North Sea Gas Basin. The reservoir is formed by the Lower Permian Leman Sandstone Formation, lying between truncated Westphalian Coal Measures and the Upper Permian evaporitic Zechstein Group which form source and seal respectively. Reservoir permeability is very low, mainly as a result of compaction and diagenesis which accompanied deep burial of the Sole Pit Trough, a sub basin within the main gas basin. The Leman Sandstone Formation is on average about 715 ft thick, laterally heterogeneous and zoned vertically with the best reservoir properties located in the middle of the formation. Porosity is fair with a field average of 11.1%. Matrix permeability, however, is less than one millidarcy on average. Well productivity depends on intersecting open natural fractures or permeable streaks within aeolian dune slipface sandstones. Field development started in 1988. 24 development wells have been drilled to date. Expected recoverable reserves are 753 BCF.

scholarly journals The Waitsia Field, onshore North Perth Basin, Western Australia

2016 ◽  
Vol 56 (1) ◽  
pp. 29 ◽  
Author(s):  
Neil Tupper ◽  
Eric Matthews ◽  
Gareth Cooper ◽  
Andy Furniss ◽  
Tim Hicks ◽  
...  
Keyword(s):  
Flow Characteristics ◽  
Development Planning ◽  
Upper Permian ◽  
Depth Interval ◽  
Lower Permian ◽  
Minimal Processing ◽  
Gas Field ◽  
Full Field ◽  
Field Development ◽  
Primary Porosity

The Waitsia Field represents a new commercial play for the onshore north Perth Basin with potential to deliver substantial reserves and production to the domestic gas market. The discovery was made in 2014 by deepening of the Senecio–3 appraisal well to evaluate secondary reservoir targets. The well successfully delineated the extent of the primary target in the Upper Permian Dongara and Wagina sandstones of the Senecio gas field but also encountered a combination of good-quality and tight gas pay in the underlying Lower Permian Kingia and High Cliff sandstones. The drilling of the Waitsia–1 and Waitsia–2 wells in 2015, and testing of Senecio-3 and Waitsia-1, confirmed the discovery of a large gas field with excellent flow characteristics. Wireline log and pressure data define a gross gas column in excess of 350 m trapped within a low-side fault closure that extends across 50 km2. The occurrence of good-quality reservoir in the depth interval 3,000–3,800 m is diagenetically controlled with clay rims inhibiting quartz cementation and preserving excellent primary porosity. Development planning for Waitsia has commenced with the likelihood of an early production start-up utilising existing wells and gas processing facilities before ramp-up to full-field development. The dry gas will require minimal processing, and access to market is facilitated by the Dampier–Bunbury and Parmelia gas pipelines that pass directly above the field. The Waitsia Field is believed to be the largest conventional Australian onshore discovery for more than 30 years and provides impetus and incentive for continued exploration in mature and frontier basins. The presence of good-quality reservoir and effective fault seal was unexpected and emphasise the need to consider multiple geological scenarios and to test unorthodox ideas with the drill bit.

Hydrodynamic Properties of an Asymmetric Deepwater Riser Bundle

2006 ◽  
Author(s):  
Charles Zimmermann ◽  
Richard James ◽  
Blaise Seguin ◽  
Mattias Lynch
Keyword(s):  
Cross Section ◽  
Water Depth ◽  
Hydrodynamic Characteristics ◽  
Cfd Analysis ◽  
Effective Solution ◽  
Hydrodynamic Properties ◽  
Global System ◽  
Field Development ◽  
Hydrodynamic Behaviour ◽  
Deepwater Riser

The BP operated Greater Plutonio field development offshore Angola comprises a spread-moored FPSO in 1,300 m water depth, serving as a hub processing the fluids produced from or injected into the subsea wells. The selected riser system is a riser tower tensioned by a steel buoyancy tank at its top end and distributed foam buoyancy along a central structural tubular. The riser bundle is asymmetric in cross-section and this paper presents the work performed to determine the specific hydrodynamic characteristics of the design. Both basin tests and CFD analysis results are presented with discussion on some specific hydrodynamic issues: vortex-induced vibration (VIV) of the global riser tower system, VIV of individual risers, and the dynamic stability of the global system (i.e. galloping). Finally, guidelines for the assessment of the hydrodynamic behaviour of such system geometries are proposed. The results of this paper demonstrate that the Greater Plutonio riser bundle represents an effective solution in term of hydrodynamic behaviour and is not sensitive to VIV fatigue or galloping.

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