{"title":"Charge Assessment for Nitrate-Based Salt as a Phase Change Material for a Medium-Temperature Latent Storage Tank","authors":"Ismail, Y. I. Widodo, R. A. Rahman","doi":"10.2478/lpts-2024-0006","DOIUrl":null,"url":null,"abstract":"\n The present study assesses the heat characteristic of the nitrate-salt mixture as a phase change material (PCM) for a medium-temperature latent storage system (LSS). Two binary and ternary mixtures are evaluated, which demonstrate different thermal behaviour. The highest melting and latent heat capacity is obtained by KNO3(0.4)/NaNO3(0.6) at 223.8 °C and 161.5 J/g. However, it has a higher supercooling degree with a partial phase transition between 217.6 °C and 251.5 °C, making it unfeasible for a medium-temperature LSS tank. The ternary mixture (TM) with NaNO2(0.4)/KNO2(0.53)/NaNO3(0.7) demonstrates a stable phase transition with minimum partial phase transition (22.1 °C) and suitable heat of fusion (98.1 J/g). Further evaluation through static thermal profiling demonstrates that the TM has a notable performance during solid-sensible charge with a charge level indicator (CLI) around 45.3 %–49.1 %. The TM can be charged up to 85.7 % until the end stage of the phase transition. It promotes a better storage capacity with suitable performance since the system can be charged effectively at a suitable temperature range (< 160 °C) for various applications. The micrograph observation indicates some dispersed particles and local agglomeration, which makes phase stabilization as an advantageous method to promote a stable phase change process. The TM can be considered a suitable PCM for a medium-temperature LSS tank that allows for a better solar thermal renewable system operation.","PeriodicalId":43603,"journal":{"name":"Latvian Journal of Physics and Technical Sciences","volume":null,"pages":null},"PeriodicalIF":0.5000,"publicationDate":"2024-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Latvian Journal of Physics and Technical Sciences","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.2478/lpts-2024-0006","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q4","JCRName":"PHYSICS, APPLIED","Score":null,"Total":0}
引用次数: 0
Abstract
The present study assesses the heat characteristic of the nitrate-salt mixture as a phase change material (PCM) for a medium-temperature latent storage system (LSS). Two binary and ternary mixtures are evaluated, which demonstrate different thermal behaviour. The highest melting and latent heat capacity is obtained by KNO3(0.4)/NaNO3(0.6) at 223.8 °C and 161.5 J/g. However, it has a higher supercooling degree with a partial phase transition between 217.6 °C and 251.5 °C, making it unfeasible for a medium-temperature LSS tank. The ternary mixture (TM) with NaNO2(0.4)/KNO2(0.53)/NaNO3(0.7) demonstrates a stable phase transition with minimum partial phase transition (22.1 °C) and suitable heat of fusion (98.1 J/g). Further evaluation through static thermal profiling demonstrates that the TM has a notable performance during solid-sensible charge with a charge level indicator (CLI) around 45.3 %–49.1 %. The TM can be charged up to 85.7 % until the end stage of the phase transition. It promotes a better storage capacity with suitable performance since the system can be charged effectively at a suitable temperature range (< 160 °C) for various applications. The micrograph observation indicates some dispersed particles and local agglomeration, which makes phase stabilization as an advantageous method to promote a stable phase change process. The TM can be considered a suitable PCM for a medium-temperature LSS tank that allows for a better solar thermal renewable system operation.
期刊介绍:
Latvian Journal of Physics and Technical Sciences (Latvijas Fizikas un Tehnisko Zinātņu Žurnāls) publishes experimental and theoretical papers containing results not published previously and review articles. Its scope includes Energy and Power, Energy Engineering, Energy Policy and Economics, Physical Sciences, Physics and Applied Physics in Engineering, Astronomy and Spectroscopy.