Bridging molecular modeling and 3E cycle analysis in absorption cooling using biomass-based solvents

Identifier:  imarina:9499445

Handle: https://hdl.handle.net/20.500.11797/imarina9499445

Authors:  Huenuvil-Pacheco, Isaias; Viar, Miguel; Zarca, Gabriel; Urtiaga, Ane; Mejia, Andres; Llovell, Felix

Abstract:
Improving the sustainability of thermal processes has fostered growing interest in renewable, biodegradable, and non-toxic compounds. Among them, biomass-derived solvents present significant advantages over traditional petroleum-based alternatives, contributing to circular economy strategies. In this study, we develop a comprehensive thermodynamic framework to assess the potential of new refrigerant-solvent working pairs for absorption refrigeration systems (ARS). These pairs combine fluorinated refrigerants and CO2 with five green organic solvents: Propylene Carbonate, Solketal, Terpinolene, gamma-Valerolactone, and Rhodiasolv PolarClean. The solubility of refrigerants in these solvents is modeled using an extended version of the SAFT-VR Mie equation of state, incorporating descriptors for planar ring structures and polar contributions. Refrigerants are treated as non-associating but dipolar fluids, and their thermophysical properties are successfully reproduced. Mixture behavior is captured with a single, temperature-independent binary interaction parameter, enabling reliable extrapolation to process conditions. The validated model is employed to quantify the working capacity of each refrigerant-solvent pair, serving as a pre-screening tool to choose the most promising pairs for cycle simulation. Single-effect (SE) and compression-assisted (CA) ARSs are evaluated through a detailed parametric study. Then, a comprehensive 3E analysis (energetic, exergetic, and environmental) is conducted, incorporating Key Performance Indicators, including the energy and exergy coefficients of performance, circulation ratio, high-pressure levels, and the total equivalent warming impact (TEWI). Finally, the TOPSIS multi-criteria decision-making method is applied to rank the working pairs and identify the best options for each configuration, revealing that R32/gamma-Valerolactone stands out as the best working pair in CA-Cycles when environmental concerns are considered.