Print Email Facebook Twitter Absorption of CO2-NH3-H2O mixture in mini-channel heat exchangers Title Absorption of CO2-NH3-H2O mixture in mini-channel heat exchangers Author Shi, Liang Gudjonsdottir, V. (TU Delft Engineering Thermodynamics) Infante Ferreira, C.A. (TU Delft Engineering Thermodynamics) Rexwinkel, Glenn (Frames) Kiss, Anton A. (Akzo Nobel) Date 2017 Abstract Compression resorption heat pumps (CRHP) are a promising option to upgrade waste heat from industry. Alternative working fluids can further improve the efficiency of CRHP. The ternary mixture NH3-CO2-H2O has been identified as a promising working fluid for CRHP and has the potential to further enhance the coefficient of performance (COP) of the cycle compared to the traditionally used ammonia water mixture. So far the studies on the NH3-CO2-H2O mixture have focused mainly on carbon capture applications. But the desired operating conditions are different than for CRHP applications, e.g. the NH3 concentration. Additionally the absorption process with the mixture in tubular absorbers has not yet been reported. The focus of this study is therefore to investigate experimentally the absorption process of a CRHP with this ternary mixture. To reach this goal a model is developed for ammonia-water that takes into account the kinetics and mass transfer during the absorption process. To validate the model, experiments were performed for an absorption process in a mini channel heat exchanger with NH3 concentration of 35 wt%. The results show a good match between the model and the experiments. Additionally CO2 has been added to the solution and the experimental performance was compared with the experimental performance of the NH3-H2O mixture. A concentration of 2 wt% CO2 resulted in a performance increase of up to 5% however the working fluid flow became limited by pumping instabilities. Subject heat pumpsNH3-CO2-H2O mixtureNH3-H2O mixturewaste heat recoveryabsorptionmini-channel heat exchangers To reference this document use: http://resolver.tudelft.nl/uuid:f3dd8980-d142-4a49-8c97-e99ae8e46697 Publisher Stichting HPC 2017 ISBN 978-90-9030412-0 Source Proceedings 12th IEA Heat Pump Conference Event 12th IEA Heat Pump Conference, 2017-05-15 → 2017-05-18, Rotterdam, Netherlands Part of collection Institutional Repository Document type conference paper Rights © 2017 Liang Shi, V. Gudjonsdottir, C.A. Infante Ferreira, Glenn Rexwinkel, Anton A. Kiss Files PDF O.3.5.2_Absorption_of_CO2 ... angers.pdf 678.99 KB Close viewer /islandora/object/uuid:f3dd8980-d142-4a49-8c97-e99ae8e46697/datastream/OBJ/view