Experimental parametric evaluation of adsorption characteristics for silica gel - water based open-bed system for seasonal thermal energy storage

Koley, Susmita; Bao, Huashan; Roskilly, Anthony Paul; Ma, Zhiwei

Abstract

This study aims to investigate the potential of using commercial silica gel as an energy storage material in a bulk-scale open bed adsorption-based system to achieve efficient domestic heating using renewable energy sources. Designing an efficient thermal energy storage (TES) system for practical use requires understanding of the sorption properties of the adsorbent and the effects of different operating and physical parameters on the sorption process. One critical parameter that significantly affects the energy storage density when scaling up from a laboratory to a prototype system is the amount of adsorbent in the reactor. Surprisingly, this aspect has been overlooked in previous studies. To address this research gap, a laboratory-scale test rig was designed and constructed. This rig enables the evaluation of the effects of different operating parameters (such as relative humidity, flow rate, and regeneration temperature) and physical parameters (such as the quantity of adsorbent and particle diameter) on the energy storage density of silica gel and the temperature lift in the process. The water adsorption capacity of the silica gel was measured in-house to assist in future theoretical modelling of a prototype TES system. Optimum operating conditions were determined for the system, with a relative humidity of 80 %, an air flow rate of 100 L/min, and material regeneration at 120 °C. The system's performance in terms of material energy storage density and maximum temperature lift was observed for varying amounts of adsorbent, particle diameter, and regeneration temperature at these optimal operating conditions. Finally, the required storage volume to meet domestic space heating demands was estimated based on optimal discharging conditions and compared to other experimental and theoretical studies involving silica gel-based energy storage systems.

Citation

Koley, S., Bao, H., Roskilly, A. P., & Ma, Z. (2024). Experimental parametric evaluation of adsorption characteristics for silica gel - water based open-bed system for seasonal thermal energy storage. Journal of Energy Storage, 89, Article 111812. https://doi.org/10.1016/j.est.2024.111812

• Journal Article Type: Article
• Acceptance Date: Apr 19, 2024
• Online Publication Date: Apr 25, 2024
• Publication Date: 2024-06
• Deposit Date: May 8, 2024
• Publicly Available Date: May 8, 2024
• Journal: Journal of Energy Storage
• Print ISSN: 2352-152X
• Electronic ISSN: 2352-1538
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 89
• Article Number: 111812
• DOI: https://doi.org/10.1016/j.est.2024.111812
• Public URL: https://durham-repository.worktribe.com/output/2435040