MEETING THE EXECUTION CHALLENGES OF SHELL PRELUDE FLNG

Transcription

1 MEETING THE EXECUTION CHALLENGES OF SHELL PRELUDE FLNG Alain Poincheval Executive Project Director Technip, France Jun Cheol Kim EVP, FLNG Project Management Offshore Production Facilities Business Unit Samsung Heavy Industries, Republic of Korea Nicholas Kauffmann General Manager Integrated Gas Projects East Shell Projects & Technology, The Netherlands ABSTRACT Floating Liquefied Natural Gas (FLNG) has gained wide recognition as one feasible and attractive method for the monetisation of offshore gas fields. It is an exciting technology that will enable the development of gas resources where, for a range of reasons, an onshore development is not viable. FLNG can mean faster, cheaper, more flexible development and deployment strategies. Today, this recognition comes from one outstanding project. In May 2011, Shell started the entire LNG and gas industry in a new direction when it took the Final Investment Decision on Prelude FLNG and gave the Technip-Samsung Consortium, or TSC, Notice to Proceed. Prelude FLNG is a project backed with the industry s best resources. Years of careful planning and front end engineering and design have been the basis for this ground breaking project, but the current progress would not be possible without the vigilance, professionalism and collaboration of all involved during execution of this complex project. The TSC project directorate proposes to look back jointly with Shell project management over the years from notice to proceed in a paper that focuses on solving some of the expected and also the unexpected challenges that are always inevitable in a large, complex and first-of-its-kind project. Owned and presented by Host IGU Member Supporting Association

2 OVERVIEW OF THE SHELL PRELUDE FLNG THE INNOVATIVE CONCEPT AND TECHNOLOGY OF FLNG The novel concept of FLNG has been extensively studied over the last 15 years or so. It consists of a combination of several technologies that aim to liquefy natural gas offshore. FLNG solutions have the potential to place gas liquefaction facilities directly over offshore gas fields, and unlock new energy resources offshore. They will enable access to stranded gas reserves that, up to now, were too costly and difficult to exploit. The Shell Prelude FLNG project is especially well placed to help meet the growing natural gas demand of Asia. The Shell Prelude FLNG facility will chill natural gas produced in the field to 162 C (-260 F), shrinking its volume by 600 times so it can be shipped to customers, where the gas is needed. Once constructed, the facility will be towed to its location, some 475 kilometres (around 300 miles) north-east of Broome, Western Australia. There, the facility will be moored and connected to the undersea infrastructure and the whole production system commissioned. Shell Prelude FLNG will remain permanently moored at the location for around years before needing to go back to the dock for inspection and overhaul. The LNG, LPG and condensate produced will be stored in tanks in the hull of the facility. LNG and LPG carriers will moor alongside to offload the products with tandem off-loading for condensate. Most of the technologies used on the FLNG facility have been used successfully onshore by Shell. Some have been adapted or modified in order for the processes, such as liquefaction and offloading, to run at sea, as we will see later on this paper. Important attributes of Shell s Prelude FLNG design are: it can provide high production rates of 5.3 million tons per annum (mtpa) of liquids (including LNG, LPG and condensate); it can process a wide range of gas compositions and can export LPG and condensate; it uses an efficient double mixed refrigerant liquefaction cycle; it can stay on station and does not have to be moved during severe weather conditions such as cyclones, which will increase the availability of the plant. Page 2 of 12

3 SHELL PRELUDE FLNG KEY FACTS Location Depth Table 1. Key facts about Shell Prelude FLNG Browse Basin in Australia, 475km North-North East of Broome (see figure 1) ~250 metres Interests Shell 67.5%, INPEX 17.5%, KOGAS 10%, OPIC 5% Fields FLNG facility production capacity Key contractors Prelude and potentially other Shell natural gas assets in the region 5.3 million tons per annum (mtpa) of liquids: 3.6 mtpa of LNG, 1.3 mtpa of condensate and 0.4 mtpa of liquefied petroleum gas Technip-Samsung Consortium Shell Prelude FLNG is the largest floating facility ever built (see figure 2). In numbers this means: 488 metres long (more than four FIFA football pitches) and 74 metres wide. 260,000 tons of steel, the equivalent of 36 Eiffel towers. With its cargo tanks full, Prelude will weigh roughly six times as much as the largest aircraft carrier. The total storage capacity is equivalent to around 175 Olympic swimming pools. The world s largest non-disconnectable Turret Mooring System, taller than the Statue of Liberty with its base (93 metres high). Living quarters of the size of the Paris Arc de Triomphe m 3 /h of cold water will be drawn from the ocean to help cool the natural gas Celsius (-260 Fahrenheit) is the temperature at which natural gas turns into LNG and 1/600 is the factor by which a volume of natural gas shrinks when it is turned into LNG. 117% of Hong Kong's annual natural gas demand could be met by the facility's annual LNG production years is the time the Prelude FLNG facility will stay at the location. More than 600 engineers worked on the facility s design option (1.6 million hours during the engineering and design phase). Page 3 of 12

4 Figure 1. Prelude field map. Figure 2. Infographic of Shell Prelude FLNG s size in comparison to famous constructions. THE HISTORY OF SHELL PRELUDE FLNG Following the Master agreement signed with Shell in 2009, Technip started to carry out a Generic FLNG FEED (Front-End Engineering and Design) and, in 2010, it was adapted to the Prelude field. On May 20, 2011 Shell took the final investment decision (FID) on the Prelude FLNG project. The construction and integration phase of the Prelude FLNG project are well under way and commissioning has now started. Shell, Technip and Samsung Heavy Industries common aim is to deliver Prelude FLNG safely and to do it right. This means developing a facility that is safe, robust, and reliable and with high availability to enable continuous, stable LNG production. Prelude is a global project, with fabrication of components taking place all over the globe. A key location is Geoje, South Korea, where the Prelude FLNG substructure and topsides are being built at the SHI shipyard which has one of the few dry docks in the world big enough to construct a facility of this size. Page 4 of 12

5 In November 2013, the project celebrated the launch of the Prelude FLNG hull. For a whole year, steel was welded together by thousands of workers at the SHI yard to create the biggest hull ever built. Once structurally complete, and weighing approximately 200,000 tons, the hull was floated in the massive dry dock before it was towed by nine tug boats through the Geoje harbor to its new position on the quay, where it is secured by 32 heavy mooring ropes. At Geoje, the topside process and utility modules, each weighing as much as a single typical offshore platform, were installed on the hull one by one, with the final module lifted in June 2015 (see figure 3). The 140-metre flare tower (figure 4), was installed in November At the field off the North Coast of Western Australia, Technip s Deep Orient and Deep Energy have already installed 12 km of flowlines and eight PLETs. As many as 5,000 people work on the Prelude FLNG facility on any given day at Geoje. Safety and Quality are the priority at all Prelude Project locations. Together, Shell, Samsung Heavy Industries and Technip are constantly working to ensure that Goal Zero, Shell s overarching objective of no harm and no leaks, is maintained every day. Our Zero Defect objective, supporting our quality vision at site, is conducted through all the teams, including construction, vendors and commissioning, with full compliance with the flawless programme. Page 5 of 12

6 Figure 3. Last module integration onto Shell Prelude FLNG with floating crane in June Figure 4. Shell Prelude FLNG in November MANAGING THE CHALLENGES IN SHELL PRELUDE FLNG EXECUTION The challenge of Shell Prelude FLNG is to develop an offshore version of an onshore Liquefied Natural Gas (LNG) plant on an area that is one-quarter the usual size. The traditional supply chain for LNG consists of the upstream phase, the pipelines, the onshore treatment and liquefaction, the transport, the regasification and the distribution. The Shell Prelude FLNG design Page 6 of 12

7 concept allows for the four first phases of this supply chain to be centralized and operated in a single place a single FLNG Prelude. Through the engineering, procurement, commissioning, offshore installation and start-up of this project, TSC is contributing to today s most ambitious energy infrastructure project. Technip is proud of the contribution to this making of history and its support to a visionary client Shell, by using existing technologies in novel applications. However, several challenges were faced by engineers designing this first of a kind FLNG: engineering challenges, construction and commissioning challenges, and challenges in terms of project management and HSSE. ENGINEERING CHALLENGES Despite its impressive proportions, the FLNG facility is located on an area that is one-quarter the size of an equivalent plant on land. Therefore engineers had to find different and innovative solutions to optimise the space, such as to design components that will stack vertically to save space, or to build the plant to the shape of the modules (see figure 5). The operating plant, for example, will be placed above LNG storage tanks, themselves being integrated into the hull. By pumping cooling water from the cold of the ocean depths to cool the gas, this helped to reduce the size of the cooling facilities. An assembly of eight one-metre diameter pipes will extend from the facility to about 150m below the ocean s surface to deliver around 50,000 cubic metres (m3) of cold seawater each hour. This helps to cool the gas from below the facility, saving deck space. Figure 5. Shell Prelude FLNG module construction in August In terms of optimisation during engineering, deck space management, together with module congestion and weight had to be considered. This was done through two key approaches: Use of hull machinery space for certain process units. Constant assessment of module liftability with the 8,000 ton floating crane while monitoring the center of gravity and adjusting with weight shedding. At the same time, Shell and Technip engineers also had to solve several marine environment challenges: Mechanical: Page 7 of 12

8 Process: Side-by-side offloading LNG/LPG between two vessels on the high seas both of which are moving Equipment and piping loads and fatigue generated by motion (towing & in-place conditions) LNG tank sloshing over 25 years without dry docking Industrial Maturity vs. FLNG specifications Robustness for the extreme climatic conditions of the region Gas processing facilities adapted to marine environment Compact design (weight and volume) Designing for motion compared to static onshore plant Engineering: Specific new challenges for Compliance to Australian regulation and offshore safety design. To be more precise, some new technologies that have been developed for FLNG include LNG tanks that can handle sloshing, close coupling between the producing wells and the processing facility, LNG offloading arms, cooling water intake risers, turret and mooring systems, and the marinisation of processing equipment such as absorption columns and the main cryogenic heat exchangers. All of these technologies have been extensively modelled and tested to ensure they can operate safely and efficiently under marine conditions. For example, the Prelude FLNG facility has been designed to withstand to category 5 cyclones (the highest intensity on the Saffir-Simpson Hurricane Wind Scale) and winds up to 400 km/h. To make sure it can do so, a model 1/60 of 8 meters long and 4.5 tons, was used to test the behavior of the future FLNG if impacted by high winds and strong swells (see figure 6). Figure 6. Model of Prelude during test of Prelude FLNG behavior in high climatic circumstances. CONSTRUCTION CHALLENGES Page 8 of 12

9 As a consequence of the engineering challenges, the engineering/construction execution plan had to be optimised, both for the hull/substructure and topsides of the FLNG. Substructure: Full 3D model integration between hull engineering and topside engineering Early freezing of deck penetrations (piping/e&i/handling Hatches) Deck load support (deck reinforcement & doubling plate vs. deck finishing) Very early delivery of Long Lead Items installed inside the hull (ex: power generation/instrument Air Compressor). Topsides: Detail design adapted for pancake/flip-over construction. Early freezing of main skid loads to unlock primary structure work. Prioritize secondary structure design completion versus: o Main structural support design and final stress calculation. o Accommodate late vendor interface information. Early issue of isometrics to start spooling versus: o Late vendor information. o Early insertion of large bore spools prior to deck stacking. Requested on Site Date for equipment driven by deck erection and stacking sequence. Due to vertical deck stacking sequence, priority is to start fit in position of piping and then nozzle-to-nozzle work. COMMISSIONING CHALLENGES The commissioning critical path goes through utility completion, starting first with steam generation for steam blowing. As a result, construction completion (i.e. radiography, pressure testing, insulation etc.) has a strong overlap with commissioning which needs to be managed carefully through strong Simultaneous Operations (SIMOPS) management and planning. In addition, the critical path is also going through the main compressors nitrogen run and the necessity to use steam for their steam turbines drivers. This generates late completion of High Pressure Leak test and subsequently late completion of cold insulation just before sail away. PROJECT MANAGEMENT CHALLENGES To succeed with the challenges of the execution of the Shell Prelude FLNG, Technip and Samsung Heavy Industries (SHI) chose to be organised under a Consortium (Technip-Samsung Consortium - TSC) to engineer, build and deliver Prelude FLNG project to its owner and operator Shell. In the Consortium, Technip provides the overall TSC project management as well as the Utilities/Process engineering, procurement, commissioning and final offshore Hook-up and commissioning. On the other hand, Samsung Heavy Industries (SHI) performs all of the construction on Prelude and has engineering, procurement and commissioning responsibility for the hull and associated systems. TSC is contractually obliged to its client and operator of FLNG: Shell. To carry out the engineering of Shell Prelude FLNG, TSC mobilised more than 1,000 engineers during 24 months to work on the design of this first-of-a-kind project. For Samsung, this team was primarily based in France (Paris) and Korea (Geoje). For Technip, this involved the know- Page 9 of 12

10 how of its engineers in several operating centers: France (Paris), India (Chennai), Malaysia (Kuala Lumpur) and Australia (Perth). Technip relied on the expertise of two major subcontractors: SBM Offshore for the Turret Mooring System, as well as FMC Technologies for the marine loading arms which had been jointly developed with Shell. Both Technip and Samsung Heavy Industries also rely on an international vendor network, located in more than 40 countries, mainly in Europe, America and Asia. All these stakeholders work closely together respecting the same methods and standards (HSSE policy Goal Zero, Quality Zero Defect Policy). However, this makes the Shell Prelude FLNG a mega multi-center project, and as such involves significant project management challenges. Interface management and novelty management are examples of these challenges. Interface Management The mapping of the different interfaces can be shown below: Figure 7. The mapping of the different interfaces. A Collaborative mode between Technip and Samsung Heavy Industries has been a key ingredient in the Consortium s success, with all the interfaces managed and controlled by the Topsides designer (multi-query database). In particular, interface management is critical to deliver a consistent engineering package free of rework with construction, into constrained schedule priority driven by the hull early construction into the dry dock. Novelty Management within an EPCI contract The novelty management within an EPCI contract is known as a major contribution to potential failure in delivery if not properly recognized in its specificity. For Shell Prelude FLNG, novelties were mainly recognized in the following areas: Page 10 of 12

11 Turret Mooring System Mooring chains, due to size and load Water Intake Risers: 8 x 42 LNG Marine Loading Arms (side by side loading with LNG/LPG carrier) The project implemented a gate type delivery approach and followed a thorough qualification programme as shown below: HSSE CHALLENGES Safety is the primary focus in Shell s FLNG design, construction and operation, with multiple formal safety assessments at various stages of the project confirming that an FLNG facility would be at least equally as safe and reliable as other modern offshore production facilities currently in operation. The HSE studies conducted in close collaboration with Shell indicate that Prelude will be an extremely safe and reliable facility despite the new challenges. The layout of the Prelude FLNG facility reflects the following principles that were adopted at an early stage: Higher risk process and storage areas are located furthest away from living quarters (LQ). Blast-rated bulkheads, utility modules and safety gaps separate the LQ from the process modules. The Living Quarters of both the LNG carrier and the FLNG are aligned during offloading. 20m safety gaps, open process and turret areas layouts minimise the consequences of a potential incident and the likelihood of escalation. Flammable material storage areas separated from ignition sources. Lifting equipment is deployed to facilitate maintenance access. Handling routes avoid lifting over live process areas. Dual helidecks increase helicopter operations availability. Escape routes, temporary refuges and means of evacuation in sufficient number and redundancy. As an integral part of the project, the Shell 12 Golden Safety Rules are dictated to all stakeholders under direct control of Shell, Technip, Samsung and SBM, and outline the fundamental expectations for all employees and subcontractors to comply at all times. These are as follows: Work with a valid work permit when required Conduct gas tests when required Page 11 of 12

12 Verify isolation before work begins and use the specified life protecting equipment Obtain authorisation before entering a confined space Obtain authorisation before overriding or disabling safety critical equipment Protect yourself against a fall when working at height Do not walk under a suspended load Do not smoke outside designated smoking areas No alcohol or drugs while working or driving While driving, do not use your phone and do not exceed speed limits Wear your seat belt Follow prescribed Journey Management Plan Figure 8. The 12 Golden Safety Rules. CONCLUSION The challenges in the execution of the Shell Prelude FLNG facility were numerous: Developing an offshore version of an onshore LNG plant. Specially designed equipment Impact on the Layout & Logistics. Constructability (liftability, congestion, module density). Iterative design (blast, motion acceleration etc.) matching construction sequence and procurement cycle. Shell, Samsung and Technip met these challenges thanks to a mutual understanding within a multicultural environment, a fit-for-purpose mindset, a large and efficient network of engineering and expertise centers and suppliers, strong expertise in managing and delivering large-sized complex mega-projects and building mutual trust in a first-of-a-kind environment. Ultimately, the vision of Zero Defect for Quality and Goal Zero for Safety will be the true mark of success for this giant of the seas. Page 12 of 12