Performance analysis of a scalable solar-assisted pilot scale adsorption desalination and cooling system

Adsorption desalination has emerged as a promising alternative to conventional methods due to its compatibility with low-grade heat sources. This study evaluates the performance of a solar-assisted, 2-bed mode pilot-scale adsorption desalination system utilizing silica gel as adsorbent material. This system adopts a new droplet-based mechanism of feed and distillate water distribution between the tanks and the adsorption beds to ease the water vapor transfer as a possible solution to prevent a reduction of specific productivity as the system scale increases. The evaluated key performance metrics include specific daily water production, specific cooling production, coefficient of performance, and overall conversion ratio. The adsorbent material was characterized, and an appropriate isotherm model suggested to predict water adsorption. System performance was assessed under varying desorption temperatures provided by a solar water heater and different cycle durations. At a desorption temperature of 70 degrees C and a cycle duration of 30 min, the system achieved a water production capacity of approximately 3.8 m3 ton-1 day-1 and a cooling capacity of 100 W kg-1. Increasing the cycle duration led to improved performance metrics, although the rate of improvement decreased progressively. Additionally, the conversion ratio was maximized at desorption temperatures above 68 degrees C and cycle durations longer than 46 min, indicating thermodynamic efficiency. Overall, the system demonstrated promising performance as a scalable and sustainable solution for solar-assisted adsorption desalination.