Paper presented at the 6th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, South Africa, 30 June - 2 July, 2008.
Solar desalination is an appropriate method for providing
fresh water by using renewable solar energy. Solar desalination
with humidification and dehumidification process is one of the
most effective methods among solar desalination units. This
technique presents several advantages such as flexibility in
capacity, moderate installation and operating costs, simplicity,
possibility of using low temperature energy (geothermal, solar,
recovered energy or cogeneration), etc. Processes that are used
in this method are the open water cycle- open air cycle, open
water cycle- closed air cycle and closed water cycle- closed air
cycle. Process used in this work is a open water-closed air cycle
type, in which air is circulated in the unit by forced or natural
draft between the humidifier and condenser. In this paper, the
different effective parameters such as rate of water flow
entering condenser, internal temperature to the humidifier,
natural and forced air flow, etc were examined. With the
temperature increase of water entering humidifier, the amount
of produced steam and, as a result, fresh water was increased.
However, for temperature increase of water which exits from
collector the mass of salty water inflow should be decreased.
This decrease of water flow causes reduction of desalinated
water in the condenser section of the unit. Results show that
there is an optimum rate of salty water flow entering to the
unit. Besides, a considerable difference in production of present
work with almost others were observed for natural and forced
air flow.
