Adsorption Refrigeration Technologies

Abstract

This chapter introduces a comprehensive overview about the principles, challenges and applications of adsorption refrigeration systems (ARSs), as a promising sustainable solution for many of cooling and heating applications. In addition to the features and the basics of ARSs, the following topics have been covered such as characteristics of working pairs, trends in improving the heat and mass transfer of the adsorber; advanced adsorption cycles and performance and operational data of some adsorption refrigeration applications. In some details, the operating range and the performance of ARSs are greatly affected by the employed working adsorbent/refrigerant pairs. Therefore, the study, development and optimum selection of adsorbent/refrigerant pairs, particularly the composite adsorbents, can lead to improving the performance and reliability of ARSs. Regarding the enhancement of heat and mass transfer in the adsorbent bed, two methods are commonly used: one is the development of adsorbents through different coating technologies or new materials such as metal-organic frameworks, and the second is the optimization of the adsorber geometrical parameters and cycle modes. Finally, a brief on some adsorption chillers applications have started to find their share in markets and driven by solar or waste heats.

Liquid-state pyroelectric energy harvesting

“…4 Adsorption cycles by means of a four-step thermodynamic cycle, i.e., pressurization, desorption, depressurization, and adsorption, provide a cooling effect. 5 Among thermodynamic cycles, Organic Rankine and Kalina 6 have shown to provide very good results in LG waste heat harvesting for power production. The former is based on the usage of hydrocarbon-based working fluids which, absorbing heat, evaporate passing through a turbine before condense newly.…”

“…Efficiencies of the system with the KBT05 mixture flowing at different velocities, in both LH and SH conditions. 〈v〉 1 (%) 〈v〉 2 (%) 〈v〉 3 (%) 〈v〉 4 (%) 〈v〉 5 The subscript all indicated the efficiencies obtained considering all the mixture components, while PyE indicates those obtained considering the only pyroelectric effect. Figure 6.…”

The status of refrigeration techniques for vaccine storage and transportation in low-income settings

“…The cycle can then start again with the adsorption of the refrigerant by the adsorbent bed. [66]. The adsorption capacity of a working pair is assessed as the maximal amount of adsorbate (grammes) that can be taken up by the adsorbent (grammes), i.e.…”

“…The adsorbent is a porous solid element which should thus exhibit a high capacity for adsorption with temperature variation [68]. While common adsorbents consist of activated carbon, silica-gel and zeolites, common adsorbates consist of ammonia, methanol and water [66].…”

“…[70,71]. Indeed, the heat and mass transfer that occurs in sorption refrigeration greatly influences the performance of the system and represents its main technical limitation [66].…”