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October 2011 www.sname.org/sname/mt WILL LNG BE AVAILABLE AS FUEL? LNG AS A FUEL for ships is currently available in just a few places. An exten- sive infrastructure to provide LNG for ships has, however, been developed in Norway in recent years. With more LNG- fueled ships being planned, along with LNGs cost advantage over HFO or MDO and its cleaner emission characteristics, it is expected that owners of LNG termi- nals around the world and owners of LNG bunkering barges and feeders will see the supplying of LNG ship fuel as a busi- ness opportunity, and that the necessary global LNG bunkering infrastructure will be rapidly developed. A case in point is Singapore Power, which is building an LNG hub with the possibility of marine bunkering and distribution. The Triality project has used Ras Tanura as its loading terminal and the vessel is assumed to be bunkering in the Middle East Gulf only, with each bun- kering delivering LNG for a round trip. Large volumes of LNG are produced and exported in the Middle East Gulf. Ras Tanura is located close to Qatar, with the biggest LNG production and export terminal in the world. Loading is also possible in the Louisiana O shore Oil Port in the U.S. Gulf, with North America discovering an abundance of shale gas and some import terminals already plan- ning to convert for export. two tanks closer to midship to neu- tralize the trimming e ect of fuel consumption. e fuel capacity of 13,500 m 3?or about 6,000 tons?is su cient for an operational range of 25,000 nautical miles, which cor- responds to a round-the-world trip. is is the same operating range as for a typical base case VLCC today. With the selected trading pro le for Triality , bunkering can take place at one location only, e.g. in connection with cargo loading in the Middle East Gulf, such as at Ras Tunara, Saudi Arabia, or Ras La an, Qatar. With the Triality main engine and auxiliary duel-fuel engines, emissions are signi cantly reduced. CO2 emissions are reduced by some 22%, SO X and particulate matter emissions are reduced by some 94%, and NO X emissions are reduced by some 84% with the EGR system. Taking advantage of low-temperature LNG e LNG needs to be heated before it enters the main and auxiliary engines. This is partly carried out through heat exchangers. A gly- col circuit has been incorporated which will circulate cooling capacity onboard at almost no additional cost. is glycol circuit does not introduce adverse safety issues and it enables cooling for di erent purposes. Cooling of scavenging/combus- tion air to the engines is normally done by seawater. Seawater may have temperatures around 30°C and therefore has limitations. MAN has stated that cooling of scavenging air down to 10°C may improve e -ciency by up to 2-3%. Similarly, the low-temperature glycol is used to recover VOC dur- ing voyage. A baseline VLCC design vents cargo vapors to the atmo- sphere. Studies show that as much as 500 to 600 tons of VOC can be vented into the atmosphere on each roundtrip. Triality incorporates a much simpler and economic alter- native than what is used for shuttle tankers in the North Sea to recover VOC during voyage. e recovered VOC can either be recirculated into the cargo, or, as suggested in the Triality concept, be collected in sep- arate tanks and supplied as fuel to auxiliary boilers producing steam for the cargo pumps or cargo heat- ing. During loading, at rates up to 15,000 m 3 per hour, the VOC recov- ery arrangement onboard Triality is not able to recover all VOC. It is more convenient for the loading terminal to recover such VOC via the manda- tory vapor return line onboard. In addition to the applications of the cooling capabilities of LNG, additional cooling opportunities may include air conditioning, freez- ers, and coolers. Concepts on such applications are currently being developed for shing vessels. Environmental improvements summary The reduced environmental foot- print of the Triality VLCC compared to the baseline VLCC has been esti- mated as follows: r / P C B M M B T U X B U F S r $ 0 2 emissions reduction: 34% r 4 0 X emissions reduction: 94% r 1 B S U J D V M B U F N B U U F S F N J T T J P O T reduction: 94% r / 0 X emissions reduction: 82% r 7 0 $ F N J T T J P O T S F E V D U J P O E V S J O H voyage: 100% In addition, the fuel consump- tion for Triality is estimated to be 11% lower than the baseline VLCC. " G J S T U B U U F N Q U U P R V B O U J G Z U I F capital expenditures (CAPEX) and