Process electrodialysis

Electrodialysis has advantages and disadvantages. For instance, the process requires very little energy and can recover highly concentrated solutions. On the other hand, similarly to other membrane processes, electrodialysis membranes are susceptible to fouling and must be regularly replaced. 

As a foundation for this introduction, we discuss a single prototypical desalination and ion separation process—electrodialysis (ED), whose essence is as follows. 

A process that was no more than a laboratory phenomenon when the Office of Saline Water was authorized in 1952 has been rapidly developed to the point where it is now one of the most economical processes for the conversion of brackish water to fresh. This process, electrodialysis, was selected for the third demonstration plant. It will be located at Webster, S. D. The Bureau of Reclamation Laboratories in Denver, Colo., prepared the specifications for this plant which will be designed to produce 250,000 gallons of fresh water per day. Operating on water containing between 1500 and 1800 parts of salt per million parts of water, this plant will remove more than 1 ton of salt daily to produce product water with less than 500 parts of salt per million parts of water which is required to meet U. S. Public Health Standards for good drinking water. Construction specifications for this plant were available August 1, and sealed bids will be opened on October 4, 1960. 

Ion-exchange membranes are currently used not only for more or less conventional separation processes like membrane electrolysis (mainly the chlor-alkali process), electrodialysis, dialysis or electro-ultrafiltration (cf. Table 2.1), but also in various... 

Principles and applications of electrochemical remediation of industrial discharges are presented by Pallav Tatapudi and James M. Fenton. Essentials of direct and indirect oxidation and reduction, membrane processes, electrodialysis, and treatment of gas streams, and of soils, are complemented by discussions of electrode materials, catalysts, and elements of reactor design. 

Of the various membrane processes, electrodialysis, reverse osmosis and ultrafiltration are applied in water technology. They are used particularly for reduction of the salt concentration in waters with a high mineralization of natural (sea water, some kinds of groundwaters) or anthropogenic origin (wastewaters with a high inorganic pollution). 

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