Economic analysis of Organic Rankine Cycle (ORC) and Organic Rankine Cycle with internal heat exchanger (IORC) based on industrial waste heat source constraint

Abstract

Abstract In order to compare the economics of ORC and IORC systems based on industrial flue gas waste heat. 5 working fluids were selected to establish economic model of systems. The thermal performance and economy were compared, and the constraint relationship between the exhaust gas temperature and the performance of different systems was analyzed. The results show that the net power of ORC system using dry working fluid is higher than the system using wet working fluid, and the economic of the system using wet working fluid is better. The IORC and ORC systems using the same dry working fluid have an equivalent exhaust temperature with a net power difference of 0. When the exhaust gas temperature is higher than the equivalent exhaust temperature, the net power of the IORC system is higher than the ORC system; If the exhaust gas temperature is lower than the equivalent exhaust temperature, the economics of the IORC system deteriorates; the economics of the IORC system is inferior to the ORC system using the same dry working fluid.