Demineralization as an Additional 
Water Source for Arid Lands 
WILHELMUS F. J. M. KRUL 
University of Delft, and Government Institute 
for Water Supply, The Hague, The Netherlands 
In this paper a general outline will be given of the actual 
desalting processes and their possible development in the near 
future. At the end are some references to recent literature, in 
which technical details may be found. 
In arid zones saline water often occurs in the form of: (a) sea 
water at the shore, (4) brackish water in salt inland lakes, (c) 
more or less mineralized ground water. 
Economically acceptable processes of demineralization may add 
to the possibilities of solving arid lands problems. 
Up to the present demineralization has been practiced in 
special cases at relatively high costs, particularly by: (a) distilla- 
tion with vapor compression—small units in sea vessels, e.g., 
submarines, and big installations in some places like Kuweit 
(2,650 tons per day) Curacao and Aruba (3,200 and 1,600 tons 
per day); (6) ion exchange—on a rather large scale for water 
softening in industry (boiler feed water), and only on a small scale 
for demineralization; (c) distillation by solar energy—small units 
for domestic use. 
Coordination of Research 
All over the world research is being carried out to improve the 
economy of different demineralization processes. Coordination 
and cooperation have developed fast in recent years. In the 
United States it has been carried out under the Saline Water 
Conversion Program, Department of the Interior, Washington; 
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