Fresh Water for Arizona by Salt Replacement Desalination
Affiliation
Department of Hydrology and Water Resources, University of Arizona, Tucson, Arizona 85721Issue Date
1974-04-20Keywords
Hydrology -- Arizona.Water resources development -- Arizona.
Hydrology -- Southwestern states.
Water resources development -- Southwestern states.
Desalination
Water chemistry
Desalination processes
Membrane processes
Reverse osmosis
Arizona
Water treatment
Water purification
Desalination plants
Costs
Saline water
Water supply
Cost comparisons
Solvent extractions
Water yield
Salt replacement desalination
Replacer chemical
Ultrafiltration
High flux membranes
Energy requirements
Fixed gel syneresis
Metadata
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Copyright ©, where appropriate, is held by the author.Collection Information
This article is part of the Hydrology and Water Resources in Arizona and the Southwest collections. Digital access to this material is made possible by the Arizona-Nevada Academy of Science and the University of Arizona Libraries. For more information about items in this collection, contact anashydrology@gmail.com.Publisher
Arizona-Nevada Academy of ScienceAbstract
The process of salt replacement desalination proposed is believed to be able to produce vast quantities of fresh water be desalination. This method, which is a novel approach to minimizing the costs of saline water conversion, consists of the substitution of solutes in a solution to be desalted by a replacer chemical, and the low energy removal of that replacer chemical. The ultrafiltration of larger molecular sized replacer chemicals with high flux membranes increases the produce yield rate and reduces the corresponding energy requirement, with respect to reverse osmosis. In addition, the initial captial investment is less since no pressure constraining devices are required. The alteration of the osmotic pressure of the replacer solution within the process can also take advantage of energy savings through the utilization of an easily reversible reaction which synthesizes and breaks down a constituent that has a significant osmotic pressure difference between phases. Finally, the unusual process of fixed gel syneresis shows potential as a low energy salt replacement type process, but still requires extensive investigation.ISSN
0272-6106Related items
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Economic Alternatives in Solving the U. S.-Mexico Colorado River Water Salinity Problem (invited)(Arizona-Nevada Academy of Science, 1974-04-20)A proposed desalting plant is an engineering solution to the effects of a problem which could have been avoided and even now could be reduced on the farm. Water costing $125 per acre-foot will be delivered to Mexico to grow wheat, cotton, garden crops, alfalfa and safflower, of which the average value added per acre-foot was estimated at $80 for cotton and garden crops and $14 for wheat, alfalfa and safflower. The U.S. government, instead of building the desalting complex, could accomplish its purpose just as well by paying each farmer in the Yuma area, in return for the farmers reducing their drainage flow by whatever method they see fit, $114 per acre per year for the next 50 years. With proper management on the farm, the costs of managing salinity need not be high.
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United States-Mexico Water Agreements and Related Water Use in Mexicali Valley: A Summary(Arizona-Nevada Academy of Science, 1974-04-20)A summary is given of interrelated, technical and institutional events concerning the Colorado River which took place between the United States and Mexico from 1849 to 1974 with emphasis on the 1961-1974 period. Until the treaty of 1944, Mexico had had no guarantee of a specific annual quantity of water, but in the years after 1945, when a guarantee of 1.5 million acre-feet per year was established, more than that amount was available for use. Salinity problems arose, and in 1965 an agreement for a 5-year plan for alleviating the technical and political difficulties surrounding the salinity question was made. In 1973 it was agreed that the United States would build, within approximately 5 years, a facility for desalting the saline drainage water entering Mexico. Fulfillment of the technical provisions for this agreement requires, in any event, the timely provision of federal funds to construct and operate the physical works. The several states should receive assurance that their rights and those of their respective water users will not be impaired within the legal operation of the agreement.
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