Design and experimental study of a small scale adsorption desalinator

Adsorption desalinators produce potable water from seawater using low-grade heat at 50-90 degrees C. The technology has been proven using several experimental systems, but their sizes are too large to allow efficient further development by testing novel adsorption materials and components. In this study, we introduce the world's most compact adsorption desalinator with a bed size of 0.2 kg silica gel. The system achieves a Specific Daily Water Production of 7.7 kg(water) per kg(silica-gel) and day. The performance is comparable to the best performing system to date proving that the downscaling is not detrimental. Moreover, the tests demonstrate the benefits of simple heat integration between the adsorber beds, which reduces energy consumption by 25% and increases the Performance Ratio to 0.6. The importance of heat integration is further highlighted in an unprecedented thermal response experiment, which evaluates the partition of energy input in terms of sensible heat and heat of desorption.