Towards optimal mixtures of working fluids: Integrated design of processes and mixtures for Organic Rankine Cycles

J. Schilling, M. Entrup, M. Hopp, J. Gross and A. Bardow

Renewable and Sustainable Energy Reviews, 2021, vol. 135, issue C

Abstract: Organic Rankine Cycles transform low-temperature heat from sustainable sources into electrical power. Exploiting the full potential of a low-temperature heat source requires the optimal combination of Organic Rankine Cycles and working fluid. Today, working fluids are commonly pure components. However, mixtures can significantly improve the process efficiency due to their favorable temperature-glide during evaporation and condensation. In this work, we present a method for the integrated design of Organic Rankine Cycles and working fluid mixtures, so-called 1-stage Continuous-Molecular Targeting Computer-aided mixture and blend design (CoMT-CAMbD). In 1-stage CoMT-CAMbD, the physically-based perturbed-chain statistical associating fluid theory (PC-SAFT) equation of state is used to model both, the equilibrium and the transport properties of the mixture. A CAMbD formulation enables us to consider the molecular structure of the mixture components as well as its composition as degrees of freedom during process optimization. A detailed sizing of the equipment allows us to optimize not only thermodynamic but also economic objectives. 1-stage CoMT-CAMbD is demonstrated for the design of an Organic Rankine Cycle for waste heat recovery. The method identifies the optimal working fluid mixture from several million possible mixtures jointly with the corresponding optimal process and equipment, e.g., the mixture propane/diethyl ether maximizing the net power output (Pnet=295kW) or propene/propionaldehyde minimizing the specific investment cost (SIC=3479€ /kW). The presented method allows us to rigorously analyze the potential of optimal mixtures compared to pure components for varying heat source and cooling medium of the process and systematically exploit the potential of working fluid mixtures for Organic Rankine Cycles.

Keywords: CoMT-CAMD; Computer-aided mixture design; PC-SAFT; Organic Rankine Cycle (search for similar items in EconPapers)
Date: 2021
References: View references in EconPapers View complete reference list from CitEc
Citations: View citations in EconPapers (8)

Downloads: (external link)
http://www.sciencedirect.com/science/article/pii/S1364032120304688
Full text for ScienceDirect subscribers only

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:eee:rensus:v:135:y:2021:i:c:s1364032120304688

Ordering information: This journal article can be ordered from
http://www.elsevier.com/wps/find/journaldescription.cws_home/600126/bibliographic
http://www.elsevier. ... 600126/bibliographic

DOI: 10.1016/j.rser.2020.110179

Access Statistics for this article

Renewable and Sustainable Energy Reviews is currently edited by L. Kazmerski

More articles in Renewable and Sustainable Energy Reviews from Elsevier
Bibliographic data for series maintained by Catherine Liu ().