Application Analysis of Organic Rankine Cycle Technology to Recover Ship Waste Heat and Construction of Experimental Bench

Under the environment that the International Maritime Organization (IMO) will have stricter requirements for ship energy conservation and emission reduction, the use of organic Rankine cycle (ORC) technology to recover ship waste heat for power generation is one of the most promising methods. According to the grade characteristics and distribution characteristics of ship waste heat under different working conditions, this paper theoretically evaluates the feasibility of recovering exhaust gas waste heat, scavenge air cooling waste heat, and jacket cooling water waste heat, and summarizes the application status of using ORC technology to recover ship waste heat. It is proposed that ORC using multiple heat sources to recover is the future development trend. However, the safety of the applicable working fluid, lower actual efficiency, and longer input payback period are still bottlenecks that limit the application of ORC technology on ships. At the same time, for the subsequent in-depth research of ORC technology to recover ship waste heat for power generation, this paper uses a scroll expander as the core part to build an ORC system experimental bench for recovering ship waste heat. R245fa is used as the circulating working fluid. The 120 °C -150 °C high-temperature steam generated by the electric steam boiler and the 70 °C -90 °C hot water generated by the hot water device are used to simulate the exhaust gas waste heat and jacket cooling water waste heat of the marine diesel engine, respectively. The preliminary test results show that the basic ORC system can produce the maximum net output power of 526 W with heat source of 90 °C and hence the bench can work in order.