ChE Graduate Student Jiaming Xu Now Published in AIChE Journal
ChE PhD Graduate Student Jiaming Xu co-authored a paper with ChE Associate Professor Francisco Hung and Associate Professor Steve Lustig titled “Power generation from waste heat: Ionic liquid‐based absorption cycle versus organic Rankine cycle” which was published in the AIChE Journal.
Aspen Plus® simulations using the Peng‐Robinson (PR‐EOS) and the COSMO‐SAC models were performed to study absorption power cycles (APCs) using mixtures of R‐134a with two ionic liquids, [C2C1im][Tf2N] or [C6C1im][Tf2N], and compared against an R‐134a organic Rankine cycle (ORC) operating under similar conditions. The PR‐EOS results were in agreement with calculations from a PR model fitted to the R‐134a + IL experimental phase equilibrium data. The APCs have similar efficiencies and outperform the ORC by 3%–46%, with the largest differences observed when operating with lower grade (lower TH) heating sources, lower quality cooling (higher TL), and lower subcooling in the pump inlet stream. The PR‐EOS and the Conductor‐like Screening Model Segment Activity Coefficient (COSMO‐SAC) results follow similar trends, but numerical discrepancies are observed in the cycle efficiencies and stream flow rates and compositions due to differences in solubilities and enthalpy changes between both models, suggesting that improvements are needed to increase the accuracy of COSMO‐SAC for these systems.
This work was partially supported by the National Science Foundation (CAREER Award CBET‐1649455), and by Northeastern University. Computational resources for this research were provided by the College of Engineering Computer Center and by Information Technology Services, both at Northeastern University. Francisco Hung is deeply grateful to Keith E. Gubbins, his PhD advisor and friend and to whom this manuscript is dedicated, for all his support and the positive impact he has had in Francisco Hung’s career and life.