Exergy analysis of cascade Ethylene-Propane Rankine cycle with cold energy recovery of LNG

摘要

Cascade Rankine power cycle is suitable for cold recovery in a CCHP system which uses LNG as the primary energy. It has the advantages of low operating pressure and high energy efficiency. Exergy analysis of a typical cascade ethylene-propane Rankine power cycle is conducted. The results show that the exergy losses mainly occur in the low temperature part of the cycle. The exergy loss in the LNG-ethylene heat exchanger could reach about 46% of the total exergy loss. Therefore, the reduction of the exergy losses in the low temperature is important for the improvement of the performance of cascade power cycle.