Abstract
Results presented of a study conducted in the Wadi El-Hai area of Libya to evaluate certain desalination methods and the effects of desalted water on tomatoes and beans grown in the area. The response of tomatoes and beans to drip irrigation with and without water retention agents in the soil was tested. A solar still was constructed for drip irrigation; evaluation of its cost and performance is presented, as compared with an electrodialysis process. Given locally prevailing indices for prices and land productions, benefits are likely to exceed costs for an average products value of $0.47/Kg with the electrodialysis method and $1.15/Kg with the solar method. The solar technique is competitive if stills can be constructed at $10/m2 pool area with a yearly average performance of 3.5 L/m2d. Results indicated no significant difference between conventional and drip irrigation unless a water retention agent is involved, in which case the growth rate increases. (Jahns-Arizona)