Technical-environmental assessment of low-temperature waste heat recovery technologies for marine diesel engines


Tan Sang Le†, Van Vang Le‡, Thanh Hai Truong‡, Van Viet Pham‡,*


† Institute of Engineering, Ho Chi Minh City University of Technology (HUTECH), Ho Chi Minh
‡ Institute of Maritime, Ho Chi Minh City University of Transport, Ho Chi Minh city, Vietnam

Corresponding Author Email: [email protected]

This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Currently, diesel engines are still the most widely used option to power many types of ships. Modern large diesel engines are about 50% efficient in using the fuel’s calorific value and the rest is lost to the environment as waste heat. Moreover, the rise of fuel prices due to the depletion of fossil fuel energy and unlimited carbon dioxide let-off are creating a renewed interest in techniques to increase the thermal efficiency ofmarine diesel engines. The efficient use of waste heat energy can improve the efficiency of the propulsion system and reduce emissions, by using a dedicated waste heat recovery system for power generation or for heating and drying needs. Different types of waste heat recovery technologies available onboard ships have been discussed from the perspective of technical principle and application feasibility. The objective of the paper is to focus on evaluating and analyzing the technical characteristics of typical heat utilization cycles including Kalina cycle (KC) and Rankine cycle (RC) to highlight the flexible application of KC and RC on ships. Furthermore, this work mainly focuses on evaluating the efficient heat utilization of low-temperature waste heat sources that are difficult to exploit through thermal cycles. As a result, the article drew the conclusion that waste heat recovery and its utilization will remain a good prospect in future marine engine application.