Evaluation of capacitive deionization desalination technology for irrigation

Desalination of brackish groundwater has great potential to alleviate the problem of the limited water resources in Egypt. In this paper, we studied the desalination of brackish water for irrigation purposes using capacitive deionization (CDI) technology. We investigated a modular unit for use in greenhouses (GH). A GH for the production of tomato requires about 3.2 m(3)/d of water. The target CDI unit has a production capacity of 32 m(3)/d for irrigation of 10 greenhouses from brackish water. The paper provides an extensive simulation study to illustrate the influence of various design parameters and to unveil the CDI technology pros and cons and its inherent limitations. Although the CDI unit provides comparable energy consumption to typical reverse osmosis units, it does not require frequent replacement of membranes, and the activated carbon can easily be manufactured using local material.