Inverted trickle solar still: effect of heat recovery

The inverted trickle solar still, which has been recently developed, is improved mainly by adding a heat exchanger inside the condenser. The exchanger recovers part of the heat released in the condensation process and utilizes it in heating the saline water feed. This improvement, in addition to insulating the sides of the still and increasing the flow rate of the saline water feed, resulted in increasing the productivity from about 2.5 l/d to 2.8 l/d during the month of May. This improvement, which amounts to about 12%, is related mainly to the condensate production. This productivity was also increased by about 42% for a flow rate increase of 50%. A mixture of condensate and intermediate product at a rate of 8.2 l/d and a salinity of 7130 ppm may be obtained, which is suitable in some types of agriculture.