Diseño de un sistema de recuperación de calor de un motor de combustión para desalinizar agua de mar

Abstract

CONDITION FOR PUBLICATION OF PROJECT. This work presents the conceptual design of a seawater desalination system based on the recovery of waste heat from an internal combustion engine, with the objective of contributing to sustainable energy solutions for water supply. The problem arises from the increasing scarcity of potable water worldwide, in contrast with the abundance of seawater, which has driven the development of desalination technologies. The proposed system integrates a finned tube heat exchanger and an evaporator–condenser unit, dimensioned through energy balances and heat transfer correlations, and later validated by CFD simulation. The theoretical analysis yielded an overall heat transfer coefficient of 888 [ 𝑊 𝑚2 𝐾 ] and an estimated distilled water production of approximately 3673 L/day, depending on operating conditions. However, CFD simulation reflected a less optimistic scenario, with an average overall coefficient of 96.6 [ 𝑊 𝑚2 𝐾 ], a seawater outlet temperature of 46.2 °C, and a corresponding production of approximately 40 L/day. These discrepancies are attributed to the idealized assumptions of the analytical model, such as uniform flow distribution, typical fin efficiency, and the absence of fouling resistances. The results confirmed the partial technical feasibility of the heat recovery principle, while also highlighting the need to optimize geometry, select more corrosion-resistant materials, and validate the design through experimental prototypes. The main contribution of this work is to provide a comparative technical diagnosis between theoretical calculations and numerical simulation, serving as a reference for future improvements in the design of sustainable water production systems. Keywords: desalination, heat recovery, waste heat, heat transfer, finned tubes heat exchanger, evaporator-condenser.