LNG production for Midscale

GASTECH 2012 London

LNG BARGE DEVELOPMENTS MOVE FORWARD

Javid Talib Vice President, Floating LNG Program Manager

Brian Price LNG Advisor

Bob Germinder Vice President – Project Director

Alan Kamp Vice President – Senior Project Manager

OCTOBER 8-11, 2012

GASTECH 2012| LNG BARGE DEVELOPMENTS MOVE FORWARD

BLACK & VEATCH | www.bv.com

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LNG BARGE DEVELOPMENTS MOVE FORWARD

Javid Talib Vice President, Floating LNG Program Manager

Brian Price

LNG Advisor

Bob Germinder Vice President – Project Director

Alan Kamp

Vice President – Senior Project Manager

Black & Veatch Corporation Overland Park, KS, USA

www.bv.com

Abstract As the industry looks for new LNG supplies, the application of LNG barges has taken new life in the past two years. Two projects have completed FEEDs and are ready to move into the project execution. These projects are being developed on barge structures that can be easily fabricated and outfitted in a number of yards around the world. Two main facility configurations have been advanced into FEED and beyond considering onboard storage and storage in the form of an LNG tanker birthed nearby. The LNG can then be transferred to another tanker for shipment or switched out as desired.

With real estate on floating structures at a premium, compact facilities are a must. In barge LNG concepts, complete process systems are included such that the barge is self sufficient. For these compact, barge mounted units, the single mixed refrigerant process (SMR) is being used for the liquefaction system. The SMR process is readily modular and scalable to fit the production profile of these projects. Many configurations ranging from 0.5 MMTPA to 2.8 MMTPA have been developed to fit the dockside or near-shore (benign ocean conditions) barge LNG developments. The concept also can take advantage of available power from onshore wherever available for using motor driven refrigeration compression. Thus, the main refrigeration driver can be gas turbine drive or motor drive. Also, air and water cooling are contemplated on different sites.



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Introduction During the past decade many owners have investigated floating LNG facilities to bring new reserves to market. The majority of these projects have involved outfitting LNG tankers with gas processing and liquefaction facilities. While these concepts provide some interesting solutions to bring stranded reserves to market, many FLNG concepts have stalled due to complex solutions and high costs. A few are moving forward albeit at a slower pace.

One unique solution that has moved to the forefront of the industry is to utilize a barge mounted liquefaction plant for dockside or near-shore application. The topsides process facilities are a combination of stick built and prefabricated sub-assemblies much as would be used in an onshore situation in highly developed locations such as the U.S. These sub-assemblies or skids are then mounted on the barge structure. Such barges are often referred to as “work or dumb” barges, i.e., no propulsion systems. The barge can either be designed without onboard LNG storage or with internal storage pressure vessels. In either arrangement, the support structure for the liquefaction facilities becomes a simple and low-cost way to accommodate the liquefaction unit. Unlike traditional FLNGs with LNG containment system in the ship hull, the simple barge concepts do not have any complex topside to hull integration needs.

Barge units tend to target smaller gas production locations and locations with limited impact from ocean movements. The first projects to move forward involve 0.5 and 0.75 MMTPA designs. Also, both projects can accommodate additional identical barges for phased LNG production. An additional aspect of these barge units is the simplified design means a much shorter fabrication and launch schedule versus the large ship-based concepts. The barges can be competitively fabricated anywhere in the world and topsides can either be build and integrated at the same yard or the barge can be towed to any desired fabrication facility. Equipment is deck-mounted where feasible at reduced cost versus large offshore structural modules. Structural elements are easily modeled into barge designs.

Liquefaction Technology A successful barge-mounted project requires the application of liquefaction technology that is space-efficient and energy-efficient. The technology of choice for these applications is the Single Mixed Refrigerant (SMR) process. The SMR process is the work horse of the small and mid-scale LNG industry with over 85% of the units in operation. A leader in the SMR business is the Black & Veatch PRICO® SMR technology. With 19 units in operation and 15 additional units under contract, the PRICO® process is well proven in a range of LNG project sizes. Other processes such as nitrogen refrigeration and expander technology have been suggested for offshore LNG but the dramatic loss of efficiency in these processes limits their appeal for actual applications. The low efficiency not only impacts the energy consumption but also leads to sharply increased deck space and the consequent capital cost. On the other end of the project scale, base load processes such as C3-MR and DMR have been promoted for scale down to FLNG applications. However, the extreme complexity and high capital cost make them less suitable for smaller FLNG. In addition, these large FLNGs tend to use complex processes with tall spiral wound exchangers that may have issues in floating environments.

The PRICO® SMR process (Figure 1) is normally the lowest cost design for small and mid-scale liquefaction systems due to its low equipment count and flexibility in handling a broad range of feed gases. This technology, in contrast to the others discussed, has only a single compression system for the refrigeration. Also, the main exchanger is a very simple plate-fin unit with a minimal number of connections. This results in a simple, easy to operate liquefaction process. The system is



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designed such that during a shutdown the refrigerant inventory is maintained in the system. No venting or pressure relieving is needed. This type of process has thus become the workhorse of the small and mid-scale LNG industry and ideal for offshore floating LNG applications.

FIGURE 1: PRICO® LNG Process

Improvements in the PRICO® process by Black & Veatch over the years have resulted in a 25-35% reduction in power versus older facilities. Generally, these processes require about 260-370 kW per MMSCFD of LNG capacity. The exact value depends on the system design parameters such as feed gas pressure, ambient conditions and process specifications. Besides the refrigerant compressor, the main exchanger is the key piece of equipment in the liquefaction system. The main exchanger (Figure 2) is an aluminum plate-fin core or cores in a carbon steel box. The box is filled with perlite for insulation. All connections are external to the box, which eliminates any leak potential inside the box. Modern SMR plants have much more efficient main exchanger designs than do the more complex facilities using spiral wound exchangers. Figure 3 shows a facility where a 1970 vintage spiral wound unit was replaced with a modern plate fin unit, which is 1/3 the size and half the cost.



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FIGURE 2: PRICO® Main Exchanger (BAHX – Cold Box)

FIGURE 3: Main Exchanger Comparison



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The other critical item in an LNG process is the refrigeration compressor. Black & Veatch favors a simple, repeatable design using a single-body, two-section unit. This compressor can be purchased in a wide range of sizes from about 5 MW to over 100,000 MW. Figure 4 shows an MR compressor for a PRICO® plant. Being a barrel style unit, the bundle can be pulled without disconnecting the overhead piping. This is also a very economical design versus other systems such as are used with spiral wound units. This configuration provides a compressor that is easier to maintain than multiple body units required in more complex processes. In these other processes, the refrigeration loop requires a barrel style unit AND a horizontally split compressor. This is not only a more expensive unit but is much more difficult to provide maintenance on the horizontally split unit.

FIGURE 4: Refrigerant Compressor

One of our key suppliers for this type of unit is Dresser Rand. They make a family of compressors called Datum units that are tagged by capacity from a D-4 (smallest) to D-28 (largest). We currently have 10 units from Dresser Rand going into projects in China. Two are in operation and the others are in various stages of fabrication. The unit shown in Figure 4 is a D-16 unit that is now in operation in a recent project.

Compressor sizes for offshore units range from D-20 to D-26 units depending on the capacity. All these units have the same identical compression ratio and wheel count. The difference is the body size, which matches the unit volume throughput. Other vendors have similar equipment lines.

All components of PRICO® process have been assessed for marine application subject to motion, both from operability and mechanical strength design aspects. As such, the dockside or near-shore barge LNG application in protected waters provides much benign sea conditions for motion effects.

Marine Classification The owner of the barge needs to make an early determination for marine classification requirements for the barge. Early identification is essential to the development of the basic design and approach to be taken during execution to avoid cost impacts and schedule delay. Black & Veatch has worked with several classification agencies to establish and identify major components to be classified or built to class requirements. Most of the key suppliers have been able to confirm their previous class experience.



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The addition of marine classification impacts safety and hazard reviews. Early engagement by class in the feasibility study phase has helped the project teams identify key design criteria when developing layouts. The designs have been reviewed for egress, fire and safety, spills, dropped objects, and normal operations of the barge. Black & Veatch’s designs have undergone this level of design and HAZID reviews.

Barge Configurations There are several factors dictating barge layout configurations. The simplicity, flexibility and scalability of PRICO® process allow a wide range of liquefaction capacities in single- or multiple-train configuration. There are several system with options from which any configuration can be built around depending up on the location, power availability, permitting constraints for use of water cooling and the LNG offloading/export strategy. The barge could be self sufficient or utilize some systems located on shore at dockside.

Figure 5 lists some of the basic systems and the available options. A barge configuration could either use a turbine drive or electric motor drive with either water cooling or utilize aerial cooling. Another option to be considered is the LNG storage. Smaller capacity pressurized LNG tanks can be located in the barge for load out to small tankers periodically. The size of the storage and tanker sizing would be for smaller size deliveries to users. Other option is to use a full-size LNG tanker for LNG storage. The tanker would be berthed nearby and would accept the LNG production from the barge. The LNG can then be loaded to another tanker. Alternatively, the tanker being used for storage can be switched out with an empty tanker and taken to the final delivery point. The LNG production on the barge can continue filling the smaller LNG tank on board or located onshore.

LNG BARGE CONFIGURATION OPTIONS FOR NEAR-SHORE APPLICATION

SYSTEMS OPTIONS

LIQUEFACTION CAPACITY 0.5 ~ 1.4 MMTPA SINGLE TRAIN

1.0 ~ 2.8 MMTPA MULTIPLE TRAINS

REFERIGERATION COMPRESSOR DRIVER GAS TURBINE

ELECTRIC MOTOR

COMPRESSOR INTERSTAGE COOLING AIR

SEA WATER/FRESH WATER

BOILOFF GAS COMPRESSION ON BARGE OR ON STORAGE SHIP (FSU)

ONSHORE

GAS PRE-TREATING & DEHYDRATION ON BARGE OR ONSHORE

LNG STORAGE ON BARGE (BELOW DECK) OR SIDE-BY-SIDE LNG FSU

ONSHORE

UTILITIES ON BARGE

FROM ONSHORE

POWER ON BARGE GENERATION

FROM ONSHORE GRID /GEN

CONTROL ROOM/ACCOMMODATION ON BARGE OR ON FSU

ONSHORE

FIGURE 5: Barge Configuration Options



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For LNG barge applications, many conceptual configurations have been developed for capacity ranging between 0.5 MMTPA and 2.8 MMTPA in single and multiple PRICO® liquefaction trains, of which two general configurations have been advanced through the FEED stage. The first uses a turbine driven refrigeration compressor with water cooling. Also, included is a power generation block to provide power for the entire barge such that the barge does not depend on external power supply. The second configuration utilizes a motor-driven refrigeration unit with aerial cooling. Power would be supplied from a third-party power generation facility from onshore. Each of these configurations has advantages for a particular site location. Also, consideration on subsequent projects has been given to a turbine drive plant with aerial cooling.

Figure 6 and 7 show general arrangements for the two options. As can be seen from these two figures, in either the turbine/water case or the motor/air design, a similar size barge can be used for the liquefaction facility. Also these choices can be made with our without on-board LNG storage.



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FIGURE 6: Example Barge Layout with Gas Turbine and Water Cooling



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FIGURE 7: Example Barge Layout with Electric Motor Drive and Aerial Cooling



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Project Applications EXMAR’S FLRSU- The turbine/water design has been moved from FEED to final design and fabrication by Exmar. This barge will be located offshore Colombia, South America, and will provide LNG to local users in the Caribbean market. Figure 8 shows the Exmar project concept as it is being developed into detailed design. The barge will process 72MMSCFD of gas coming in at 77 bars pressure to produce 0.5 MMTPA of LNG product. The topsides process facility will handle the feed-gas stream to remove the CO2 and water in the gas treating and dehydration units. The liquefaction unit will be driven by a LM2500+ gas turbine with a site rating of about 24 MW. The LNG will be produced to on-board storage tanks sized for 16,000 m3 of LNG in three tanks. The barge will be designed to continuously load up to 160,000 cm LNGC via a FSU moored alongside with the longer term plan to load out 10,000 m3 LNG tanker for transport to clients in the Caribbean market. The process facility will be designed and built in accordance with Marine Classification requirements to handle the flash and boil off gas from storage and loading. All such low-pressure gas will be used for fuel or recondensed to LNG. A portion of the fuel will be used for on-barge power generation. Engine driven generators in a 3 x 50% configuration will provide reliable power for the barge operation. All other utilities and makeup systems will be located on the barge such that the barge will be self sufficient.

FIGURE 8: Exmar FLRSU Barge



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The Exmar FSLRU (floating storage, liquefaction, regasification unit) barge is being executed by a global team. The barge and topsides will be fabricated in China by Wison, a world-class shipyard/fabrication facility, utilizing cost-effective Chinese labor managed by highly qualified western management utilizing rigorous quality control and quality assurance techniques assuring superior quality, a true case where “East meets West”. The topsides design and equipment will be supplied by Black & Veatch. The entire process barge will be checked out in the Wison yard before being transported to the site. The target date for startup of the project is 1Q 2015 and as such will represent the world’s first modern FLNG application to come on stream.

DOUGLAS CHANNEL, CANADA Douglas LNG has chosen a different design for this facility application. This project, slated for Kitimat, British Columbia, is designed to process 100MMSCFD and produce 0.75 MMTPA of LNG. The project is based on using a motor-driven liquefaction unit with aerial cooling. The power for the liquefaction will come from an onshore power plant. The all electric unit with aerial cooling is designed for a low environmental impact. As shown in Figure 9, the LNG will be produced to a nearby tanker for storage. The LNG then can be loaded to another tanker for transportation to market. Alternatively, the storage tanker can go to the eventual market and another tanker put in its place. A 20,000 m3 onshore tank has been included in the project to accommodate this option.

FIGURE 9: Douglas Channel, Canada, LNG Barge

The Douglas barge is intended to be a grounded barge. This eliminates the problems with large tidal changes in the inlet. Also, a second barge can be located adjacent to the barge to double the LNG capacity. The Douglas project is nearing completion of the FEED and is expected to go on line in 2015.

Project Costs The project cost depends on the specific barge configuration for a given project. Several options to be considered are shown in Figure 5. For a given liquefaction capacity, the project cost would be a combination of costs associated with the facility selected on board as well as cost for developing any required onshore facilities



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Having completed several conceptual studies with two of these concepts advancing beyond FEED, enough cost data has been developed to support conceptual planning for a variety of barge configurations. Figures 10-12 provide cost and weight information utilizing PRICO® liquefaction process with certain configuration as noted in the footnotes. These curves are indicative and provided as guidance in project conceptual planning. As a caution, the LNG barge project cost really depends on many factors and available options. Appropriate adjustment would be needed for configuration and locations other than as described in footnotes. The cost curves have been developed using Electric Motor Driver for refrigeration compressor and air coolers for interstage cooling. Gas turbine drivers add about 8% cost to the total where as water cooling adds about 5% to the total. If both gas turbine and water cooling are used, the cost would increase by 13%.

It is suggested that project-specific pre-FEED and FEED study for selected options/configuration needs to be performed where higher level of accuracy is required for advancing the project. While projects may be similar, no two are alike due to many available options as highlighted in Figure 5. The LNG production capacity would also vary depending upon the feed gas composition, pressure and ambient temperature at the specific location.

FIGURE 10: Indicative LNG Barge Cost



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FIGURE 11: Barge LNG Cost – US$/T of LNG



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FIGURE 12: Barge LNG Topsides Indicative Weight

Conclusion The focus on a simple process solution and a simple barge structure is making barge projects a reality in the LNG supply market. After many years of conferences and discussions on FLNG units, the time has come for projects to move forward and kick off the application of FLNG to real locations. A first step has been taken with the full release by Exmar with their FLSRU project slated for startup 1Q 2015, the world’s first floating LNG Barge. The barge LNG concepts for small to midscale facilities promoted by Black & Veatch with PRICO® SMR is gaining significant momentum considering its simplicity, flexibility, cost effectiveness and shorter schedule to producing LNG in near-shore application of pipeline gas for export.

LNG production for Midscale

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