Exhaust Gas Heat Recovery from a Marine Engine Using a Thermal Oil System

Abstract The recovery of exhaust gas recovery from marine engines is gaining attention in regard to saving fuel and improving system efficiency. Waste heat recovery is particularly beneficial for providing thermal and electric power, and offers efficient solutions to both economic and environmental challenges. The use of waste heat recovery technology offers the opportunity to lower fuel consumption and improve systems, and this approach also falls in line with the stringent emissions guidelines of the International Maritime Organization. This paper describes a unique exhaust gas heat recovery system in which a thermal oil system is used to heat fuel and feed cargo, in order to lower exploitation costs while also addressing environmental issues. CFD simulations of the heat recovery unit with plain and finned helix coils provide important insights into their thermal performance and pressure characteristics. The results indicate that the incorporation of fins could markedly enhance the heat transfer performance. Finned configurations are also found to have higher oil outlet temperatures, reaching up to 145.4°C in the case of a rectangular configuration. In general, this study contributes to the advancement of waste heat recovery technologies in marine applications.