Coatings for Heat Storage Reactors with Hygroscopic Salts
conference paper
One of the bottlenecks for realizing a commercial system for thermochemical heat storage using hygroscopic salts is corrosion
induced by chemical side-reactions. E.g. when Na2S hydrates are used, we basically deal with corrosion caused by the production
of the volatile H2S, threatening metal parts in the reactor and the vacuum system. Based on comparison with similar corrosion
problems, epoxy coatings were selected to protect metal parts. Because of the complex geometry of the heat exchanger, e-coating
was selected as application method. Applied coatings were tested by electrochemical impedance spectroscopy and by visual
inspection. We found that flat areas were well covered, while defects were observed around edges and connections
induced by chemical side-reactions. E.g. when Na2S hydrates are used, we basically deal with corrosion caused by the production
of the volatile H2S, threatening metal parts in the reactor and the vacuum system. Based on comparison with similar corrosion
problems, epoxy coatings were selected to protect metal parts. Because of the complex geometry of the heat exchanger, e-coating
was selected as application method. Applied coatings were tested by electrochemical impedance spectroscopy and by visual
inspection. We found that flat areas were well covered, while defects were observed around edges and connections
Topics
TNO Identifier
574313
ISSN
18766102
Publisher
Elsevier Ltd
Source title
3rd International Conference on Solar Heating and Cooling for Buildings and Industry, SHC 2014. 13 October 2014 through 15 October 2014
Pages
182-192