Adsorption Dynamics in Adsorptive Heat Transformers: Review of New Trends

This review addresses recent advances in understanding and trends in studying dynamics in adsorptive heat transformers (AHTs), which are considered as an alternative to common compression and absorption machines. Experimental data have been obtained mainly by a new large temperature jump method (LTJM) specifically developed to imitate the conditions of isobaric stages of AHTs. Here we consider merely a simple but quite realistic configuration of an adsorbent-heat exchanger (Ad-HEx) with n-layers of loose adsorbent grains (n = 1-8). Water, methanol, and ammonia are used as adsorbates. Several recommendations following from this experimental study have been checked with prototypes of adsorptive chiller in ITAE-CNR (Italy) and the University of Warwick (UK). These tests clearly demonstrated that the dynamic performance of AHT can be significantly improved by a proper management of AHT cycle and Ad-HEx geometry. The most important findings and general regularities that have been revealed by systematic studying of the adsorption dynamics of water, methanol, and ammonia in AHT systems are summarized, illustrated, and discussed in this review.