Optimal sequencing and adsorbent design of multi-bed adsorption chillers

Improving of thermal efficiency is inevitable for further dissemination of adsorption heat pumps. Here, a highly heat-integrated multi-bed switching sequence for adsorption chillers is presented to maximize regeneration of both, sensible and latent heat. The thermal coupling of the beds is investigated together with properties of the adsorbent layer using a True-Moving-Bed approach. Results are compared to the limiting thermodynamic efficiency. To account for heat and mass transfer in a consolidated adsorbent together with the motion of the adsorbent beds, a spatially one + one dimensional model is used. Adsorbent layer thickness, process cycle time and heat regeneration are optimized for maximal thermal efficiency and a given specific power density. Due to the combined optimization of material properties and cycle design, a Coefficient of Performance of up to 1.57 could be reached which is 96% of the limiting thermodynamic efficiency.