Zitieren Sie bitte immer diesen URN: urn:nbn:de:kobv:b43-556677
Heat to Hydrogen by Reverse Electrodialysis—Using a Non-Equilibrium Thermodynamics Model to Evaluate Hydrogen Production Concepts Utilising Waste Heat
- The reverse electrodialysis heat engine (REDHE) is a promising salinity gradient energy technology, capable of producing hydrogen with an input of waste heat at temperatures below 100 °C. A salinity gradient drives water electrolysis in the reverse electrodialysis (RED) cell, and spent solutions are regenerated using waste heat in a precipitation or evaporation unit. This work presents a non-equilibrium thermodynamics model for the RED cell, and the hydrogen production is investigated for KCl/water solutions. The results show that the evaporation concept requires 40 times less waste heat and produces three times more hydrogen than the precipitation concept. With commercial evaporation technology, a system efficiency of 2% is obtained, with a hydrogen production rate of 0.38 gH2 m−2h−1 and a waste heat requirement of 1.7 kWh g−1H2. The water transference coefficient and the salt diffusion coefficient are identified as membrane properties with a large negative impact on hydrogenThe reverse electrodialysis heat engine (REDHE) is a promising salinity gradient energy technology, capable of producing hydrogen with an input of waste heat at temperatures below 100 °C. A salinity gradient drives water electrolysis in the reverse electrodialysis (RED) cell, and spent solutions are regenerated using waste heat in a precipitation or evaporation unit. This work presents a non-equilibrium thermodynamics model for the RED cell, and the hydrogen production is investigated for KCl/water solutions. The results show that the evaporation concept requires 40 times less waste heat and produces three times more hydrogen than the precipitation concept. With commercial evaporation technology, a system efficiency of 2% is obtained, with a hydrogen production rate of 0.38 gH2 m−2h−1 and a waste heat requirement of 1.7 kWh g−1H2. The water transference coefficient and the salt diffusion coefficient are identified as membrane properties with a large negative impact on hydrogen production and system efficiency. Each unit of the water transference coefficient in the range tw=[0–10] causes a −7 mV decrease in unit cell electric potential, and a −0.3% decrease in system efficiency. Increasing the membrane salt diffusion coefficient from 10−12 to 10−11 leads to the system efficiency decreasing from 2% to 0.6%…
Autor*innen: | S. SolbergORCiD, P. Zimmermann, Ø. Wilhelmsen, J. LambORCiD, Robert BockORCiD, O. Burheim |
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Dokumenttyp: | Zeitschriftenartikel |
Veröffentlichungsform: | Verlagsliteratur |
Sprache: | Englisch |
Titel des übergeordneten Werkes (Englisch): | Energies |
Jahr der Erstveröffentlichung: | 2022 |
Organisationseinheit der BAM: | 3 Gefahrgutumschließungen; Energiespeicher |
3 Gefahrgutumschließungen; Energiespeicher / 3.5 Sicherheit von Gasspeichern | |
Veröffentlichende Institution: | Bundesanstalt für Materialforschung und -prüfung (BAM) |
Verlag: | MDPI |
Jahrgang/Band: | 15 |
Ausgabe/Heft: | 16 |
Erste Seite: | 6011 |
DDC-Klassifikation: | Technik, Medizin, angewandte Wissenschaften / Ingenieurwissenschaften / Angewandte Physik |
Freie Schlagwörter: | Hydrogen; Non-equilibrium thermodynamics; RED; Waste heat |
Themenfelder/Aktivitätsfelder der BAM: | Energie |
Energie / Wasserstoff | |
DOI: | 10.3390/en15166011 |
URN: | urn:nbn:de:kobv:b43-556677 |
Verfügbarkeit des Dokuments: | Datei für die Öffentlichkeit verfügbar ("Open Access") |
Lizenz (Deutsch): | Creative Commons - CC BY - Namensnennung 4.0 International |
Datum der Freischaltung: | 12.09.2022 |
Referierte Publikation: | Ja |
Datum der Eintragung als referierte Publikation: | 12.09.2022 |
Schriftenreihen ohne Nummerierung: | Wissenschaftliche Artikel der BAM |