Study of waste heat recovery system for marine diesel engine based on organic rankine cycle

This paper focuses on waste heat recovery for a marine diesel engine, using ORC technology. Two separated ORC for both waste heat from jacket cooling water and engine exhaust gas are designed, with thermal efficiency of 21.1% and 5.3%, respectively. The total net power output reaches 102.2 kW and results in 10.3% increase in engine power. To simplify the waste heat recovery, an optimized system using jacket cooling water as preheating medium and engine exhaust gas for evaporation is presented. The inuence of preheating temperature on system performance is evaluated. The net power output of the optimized system reaches 100.8 kW. Though the power output is a little lower, compact system structure, low capital cost and low space occupation are the advantages of the optimized ORC system.