This title appears in the Scientific Report :
2022
Please use the identifier:
http://dx.doi.org/10.3390/pr10030598 in citations.
Please use the identifier: http://hdl.handle.net/2128/31122 in citations.
Origin of Steam Contaminants and Degradation of Solid-Oxide Electrolysis Stacks
Origin of Steam Contaminants and Degradation of Solid-Oxide Electrolysis Stacks
Two once-through steam generators and a combination of a steam generator and a gas preheater for supplying feed gases to solid-oxide electrolysis stacks were evaluated for their carryover characteristics of contaminants from the feed-water into the steam phase. The concentrations of various trace im...
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Personal Name(s): | Schäfer, Dominik (Corresponding author) |
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Queda, Larissa / Nischwitz, Volker / Fang, Qingping / Blum, Ludger | |
Contributing Institute: |
Elektrochemische Verfahrenstechnik; IEK-14 Analytik; ZEA-3 Grundlagen der Elektrochemie; IEK-9 |
Published in: | Processes, 10 (2022) 3, S. 598 |
Imprint: |
Basel
MDPI
2022
|
DOI: |
10.3390/pr10030598 |
Document Type: |
Journal Article |
Research Program: |
Verbundvorhaben P2X-2: Erforschung, Validierung und Implementierung von 'Power-to-X' Konzepten ' Teilvorhaben Z0-2 Power-based Fuels and Chemicals Electrochemistry for Hydrogen |
Link: |
OpenAccess |
Publikationsportal JuSER |
Please use the identifier: http://hdl.handle.net/2128/31122 in citations.
Two once-through steam generators and a combination of a steam generator and a gas preheater for supplying feed gases to solid-oxide electrolysis stacks were evaluated for their carryover characteristics of contaminants from the feed-water into the steam phase. The concentrations of various trace impurities in the steam were determined by sampling the steam condensates and screening them with inductively coupled plasma–mass spectrometry for 19 elements and liquid ion chromatography and continuous flow analysis for chloride and ammonium. Steam-soluble species such as boric acid undergo complete volatilization and transfer into the steam phase. During unstable evaporation in the steam generators an extensive physical carryover of alloying metal species was observed. At realistic operation conditions for steam electrolysis, the gas preheater caused a considerable release of silicon into the steam phase. Two stack experiments were performed with common preheater temperatures and showed largely increased cell voltage degradation at higher operation temperatures. The post-test chemical analysis of cell samples revealed significant concentrations of silicon in the samples that are regarded as primary cause for increased degradation. These findings could partially explain the wide spread of degradation rates reported for solid-oxide steam electrolysis experiments. |