Experimental adsorption water desalination system utilizing activated clay for low grade heat source applications

In the present study, benefits of utilizing acid activated montmorillonite as a proposed new adsorbent material in adsorption desalination-cooling systems- have been experimentally expressed. Montmorillonite is a natural clay mineral which is composed mainly of alumina-silicate. Effect of acid activation on montmorillonite has been illustrated using infra-red spectra analysis. Adsorption characteristics (isotherm and kinetic) of acid activated montmorillonite (with 2 mole of hydrochloric acid/water vapor pair have been expressed. Isotherms results have been fitted with Dubinin-Astakhov and Sun-Chakraborty models. An experimental adsorption desalination-cooling test rig has been erected to explore the adsorption desalination-cooling systems performance with montmorillonite /water pair and axial finned tube adsorption bed design. The experimental results indicates that the daily water production is about 4.4 m³/ton of montmorillonite, its specific cooling power is 110 W/kg and the coefficient of performance is 0.41 at a driving temperature less than 100 °C. Solar energy can drive adequately the investigated system. The experiment also illustrates that the ADCS is very significant in removing all forms of salts, as proven by the weighty drop of the total dissolved salt, TDS (measured by TDS analyzer), level from approximately 40,000 ppm in seawater intake to less than 30 ppm.