Combining the psychrometric chart of humid air with water adsorption isosters: Analysis of the Ventireg process

Adsorption processes are widely used to convert heat with low- or even ultralow-temperature (ULT) potential. For instance, the adsorptive VentireG process was proposed to regenerate ULT heat and moisture in ventilation systems in cold countries. In this paper, a new approach for a deeper analysis of this process is proposed. It is implemented by plotting water adsorption isosters for a specific adsorbent directly on the common psychrometric chart of humid air. Such a combined diagram would allow the states of air and the given adsorbent to be tracked simultaneously. The merged psychrometric - isosteric diagram is plotted for five adsorbents potentially promising for the VentireG process. Their possible application in typical climatic zones of cold countries is analyzed, and the conscious choice of proper adsorbents is made. Composites salt (CaCl2, LiCl, LiBr) in silica pores can exchange up to 0.4-0.5 g_H2O/g and ensure low dew point of the outlet air. In a broader sense, this new combined diagram can be used for analyzing any open adsorption cycles, e.g., for air conditioning, desiccation, water harvesting from the atmosphere, etc. (C) 2021 Elsevier Ltd. All rights reserved.

Automated summary

Adsorption processes are commonly used to convert low- or ultralow-temperature heat into usable energy, with specific applications such as the VentireG process for ULT heat regeneration. A new approach for deeper analysis of this process involves plotting water adsorption isosters directly on psychrometric charts. This method allows for simultaneous tracking of air and adsorbent states, enabling a conscious selection of appropriate adsorbents for specific climatic zones.