The present paper reports the experimental characterization of dynamic performance of real adsorber configurations (AdHExs) based on the employment of two composite adsorbents of ethanol, developed at the Boreskov Institute of Catalysis (BIC), for adsorptive air cooling and ice making applications. In particular, the main aim of the investigation is the evaluation of the achievable specific cooling capacity of the different tested configurations under typical air conditioning cycle. Experimental tests have been performed by means of a recently developed gravimetric apparatus, based on the Large Temperature Jump approach, installed at the CNR-ITAE laboratories. Several AdHEx configurations have been analyzed to evaluate the influence of HEx geometry, adsorbent material and grain size on the overall kinetic performance. The results demonstrate that desorption stages are mainly dominated by AdHEx heat transfer. On the contrary, the adsorption stages are controlled both by inter-granular and intra-granular diffusion resistances. In particular, the intra-granular diffusion is limited by the available free pore volume. The reaction process between ethanol and inorganic salt can affect the sorption/desorption dynamics as well. As already reported in other works, also in this case characteristic adsorption times is longer than desorption one. Finally, a comparison to the kinetic performance of similar AdHEx configurations employing AQSOA-Z02/water working pair demonstrated comparable desorption kinetics, while the adsorption stage is usually twice faster for AQSOA-Z02. Starting from the experimental data, a maximum specific cooling capacity of 2.0 kW/kg has been obtained for the optimized AdHEx configuration.
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