Abstract:
One of the largest environmental problems facing today is the fresh water scarcity in the
world. On earth, 97% of total water is salt water and the remaining 3% is the freshwater.
Desalination is the process by which the salt water or the brackish water can be converted
into potable water so that the water scarcity can be reduced. Many desalination techniques
such as multi-stage flash, multi-effect distillation, and reverse osmosis have been
conventionally used but, they have limitations like high energy consumption, low water
productivity and cost. The main advantage of this technique is that it can produce cooling
along with potable water. The present study focuses on thermodynamic modelling of hybrid
solar adsorption desalination and cooling system. Initially, a numerical analysis of the
adsorption desalination and the cooling system operating with silicagel-water is carried out to
determine its performance. Two modifications are incorporated for the improvement of the
system performance. The first method is the use of suitable composite adsorbent made of
silicagel as the parent material with combinations of aluminium fumerate and PVC. The
second method is the integration of the humidification dehumidification unit to the
conventional adsorption desalination system. The system is analysed by varying the operating
parameters such as hot water temperature, cooling water temperature, condenser temperature
and salinity on the water productivity, coefficient of performance and the energy requirement.
The result reveals that the water productivity obtained from adsorption desalination and the
cooling system operating with silicagel-water is 1.3kg/cycle, whereas with that of composite
adsorbent is 1.54kg/cycle. For the hybrid system integrated with the humidification
dehumidification unit the water productivity is found to be 2kg/cycle which is 23%more than
the conventional system.
