Cycle and performance analysis of a small-scale adsorption heat transformer for desalination and cooling applications

Abstract

Adsorption heat transformers use low-grade heat to produce potable water and provide cooling at the same time. In this study, we present a comprehensive performance analysis for an experimental system featuring the world's smallest design using silica gel, which is commonly used as benchmarking material. We analyse the system performance in a thorough cycle analysis that quantifies the influence of isosteric heating times and cycle times onto the adsorption working capacity. In addition, the performance is assessed through common performance indicators for desalination as well as cooling. We found that the system achieved a Specific Daily Water Production of up to 10.9 kg w /(kg sg d) at 80°C. The combination of cooling and desalination is discussed highlighting advantages as well as disadvantages, which are often neglected. The results show that silica gel has a high performance in desalination, which decreases by more than 60 % if cooling is desired as well.

Water sorption equilibrium on 2-hydroxyethyl-trimethylammonium acetate in the temperature range 298.25–349.55K

“…One possible application for the investigated material is in sorption chillers using choline acetate as sorbent and water as refrigerant. A description of sorption cooling processes can be found in detail elsewhere [36][37][38].…”

Composite adsorbent materials for desalination and cooling applications: A state of the art

“…Recent papers illustrate adsorption materials and adsorption cooling system configurations and their combination with other cooling and desalination systems 19‐21 . The researchers continued to find new sorbent materials with high adsorption capacities like a new MOF, clays, aluminum fumarate, and copper sulfate 22‐30 or improve the existing materials.…”

“…The SDWP and SCP were 6.2‐15.4 m 3 /ton and 46.6 W/kg, respectively. Using MOF as an adsorbent, the SDWP was about 1.8 to 9.5 m 3 /ton, while the SCP and COP were about 100 to 200 W/kg of MOF and 0.5, respectively 27‐29 . Elsayed et al 30 studied theoretically the adsorption desalination system performance employing different MOF adsorbents.…”

Duplicating Freshwater Productivity of Adsorption Desalination System Using Aluminum Metal Filings

“…The coefficient of performance (COP) of 0.58 was achieved, which was significantly high compared to the previous studies. Olkis et al [10] fabricated a lab-scale ADS employing heat recovery where the SDWP reached 10 m 3 /ton/day [11,12] with a COP of 0.83. Ali et al [13] studied an ADS with two evaporators and four adsorber beds where the evaporator worked at 10 • C. The reported SDWP was 8.09 m 3 /ton of silica gel per day.…”