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October 2011 www.sname.org/sname/mt Triality introduces four innova- tive ideas for a VLCC: r U I F I V M M B O E D B S H P U B O L B S S B O H F N F O U allow for a ballast water-free ship r M J R V F ê F E O B U V S B M H B T - / ( J T V T F E as the main fuel r U I F M P X U F N Q F S B U V S F - / ( J T V T F E to eliminate VOC releases during voyages r U I F M P X U F N Q F S B U V S F - / ( J T V T F E to cool the scavenging air, thereby improving the efficiency of the main engine. Ballast-free hull Trialitys hull and cargo tank arrangement is designed for bal- last-free operation. A baseline VLCC typically carries 80,000 to 100,000 tons of ballast water on the return leg. To illustrate the amount, U P O T P G C B M M B T U X B U F S F R V B U F T to about twice the volume of the Ei el Tower, assuming it is water- tight. This gives rise to additional fuel consumption for propulsion power and pumping of ballast water. A signi cant cost saving is achieved by eliminating the installation and operation of a ballast water treat- ment system, in particular for the M B S H F Q M B O U S F R V J S F E C Z B O P S E J nary VLCC. Ballast tanks need to satisfy high coating standards? specifically, the International Maritime Organizations, or IMOs, Performance Standard for Protective Coatings?during newbuilding. e cost for maintaining the coating and possibly renewing steel in the water ballast tanks due to corrosion over the lifetime of a vessel can also be significant. The coating standard for the void space inside the Triality double hull can be somewhat reduced compared to segregated sea water ballast tanks, and there will be significant savings associated with surface preparations, coating thickness, and maintenance cost. A ballast-free hull design is therefore very attractive. Triality is designed with a near V-shaped midship section. is is to ensure su cient draft for propeller immersion and to limit slamming in the unloaded condition. With a length between perpen- diculars of 351 m and a beam of 70 m, the hull is approximately 30 m longer and 10 m wider than the baseline VLCC design in order to achieve the same cargo carrying capacity and loaded draft limita- tions. e 2001-built Stena V-Max VLCC design has proven the feasi- bility of a 70 m wide ship. e Triality hull shape has low block coefficients of 0.6 and 0.52 in loaded and unloaded condi- tions, respectively. e wetted hull Triality would use two slow- speed, two-stroke dual-fuel MAN main engines.