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Aalborg Solutions No. 9 · November 2007 Economize - and optimize your waste heat recovery Efficient heat recovery of waste heat from the diesel engine contributes considerably to the good operating economy of a ship and saves fuel for the benefit of our environment. Efficient exhaust gas economizers save money Utilizing your fuel consumption to its full potential is not only about low(ering) fuel consumption for your diesel engine or installing an advanced oil/gas burner on your boiler, but equally so about ensuring maximum waste heat recovery by installing or upgrading to the most efficient exhaust gas economizer after your diesel engines. A quite substantial amount of thermal energy (heat) is often wasted as exhaust/flue gas. In some cases, it will be advisable to replace a less efficient economizer with a more efficient one; especially so as the pay-back time can be as short as 4-5 years. Such optimization may be relevant Heat recovery from diesel engine exhaust gas by means of an exhaust gas economizer when a ship is transferred to different purposes than those for which it was originally built and where more steam or power is required. The thermal energy can also be used for preheating of combustion air, for cargo heating or water heating. MISSION™ XW economizer The most efficient exhaust gas economizer currently in the product range of Aalborg Industries is the MISSION™ XW (ex-name AV6N) which is designed with double gilled tubes. The double gilled tube design is especially suited to the ever increasing power versus weight requirements of today's oceangoing vessels as it provides a very compact unit while maintaining the large extended surface area for a high degree of heat recovery. Waste heat recovery from auxiliary engines As the auxiliary engines are increasing in size, especially on container and passenger vessels, it could be an added advantage to install waste heat recovery after these auxiliary engines, thus producing steam from waste heat during port stay and thereby reducing the environmental impact of the vessel operation. Further, we have over the past years experienced a growth in MRtankers (MR = medium range) with a boiler configuration of one large oil-fired boiler and one exhaust gas economizer after the main The efficient double gilled tubes used in the MISSION™ XW exhaust gas economizer

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