Advanced exergy analyses of modified ethane recovery processes with different refrigeration cycles

This paper presents three modified processes with different refrigeration cycles based on the recycle split vapor (RSV) process. Advanced exergy analysis is adopted to evaluate the exergy destruction forms of each component and compare exergy destruction differences among the three complex ethane recovery processes to reflect the interaction between components and identify the improvement potential of exergy destruction. The results show that avoidable endogenous exergy destruction of most equipment accounts for the highest proportion of the total exergy destruction, indicating that process improvements should focus on device performance rather than process structure. The most effective measure to reduce process exergy destruction is to improve compressor efficiency, followed by reducing the temperature approach of cold boxes and improving the separating efficiency of the columns. A sensitivity analysis shows the effects of various parameters on the four combined exergy destruction forms of demethanizer, deethanizer and refrigeration compressors, revealing opportunities for further improvement of different ethane processes to reduce exergy destruction. (C) 2020 Elsevier Ltd. All rights reserved.