Energy optimization of an engine room

The shipping industry is heavily dependent on fossil fuels for the operation of their ships. The current price increase in these fuels has made a significant impact on the shipping industry, providing incentives to reduce the fuel consumption of the ships. Further the debate about environmental impacts from combustion of fossil fuels is also becoming an incentive to reduce the fuel consumption. However, even if it is carbon dioxide that is the predominant pollutant in the public debate, the sulphur oxides, nitrogen oxides and other environmental toxins present in the fuel or formed during the combustion are the ones regulated. The pollution from these substances will be reduced with a reduction of fuel consumption but not enough to fulfil the regulations. The efficiency of the large energy consumers such as auxiliary and main engines are high, thus the effort and knowledge demanded for further improvements are high. The system cooperation on the other hand is low, heat is discarded overboard at the same time as heat supplied from electric heaters and fuel fired boilers are used to provide heat to different systems. This thesis focuses on the system efficiency of the boilers, cooling flows and pumps in the engine room considering both the possibility to reuse the waste heat, reduce the waste heat and reduce the excess usage of the equipment. The current boiler usage and the dimensioning parameters for the boiler system primarily used on board chemical tankers have been analysed. This knowledge has then been used to propose different improvements to the system. An analysis of the current energy flows has been performed and the possibility to use the energy currently discarded overboard have been evaluated. Considering the pump work in the cooling water circuits, calculations have been done to see what possible flow reductions can be accomplished and how the pump work can be reduced based on these flow reductions. For all suggested improvements there was an attempt to establish the corresponding investment costs and the savings so that it would be possible to illustrate the viability of the investments