Potential of Solar-driven CDI Technology for Water Desalination in Egypt

Abstract

Freshwater scarcity is one of the most challenging problems facing the world today. Rivers, lakes, and surface ice represent only 1.2% of the fresh water sources on earth, while ground water represents over 30% of the potential fresh water. The Egyptian quota from the River Nile is limited to 55 billion m 3 /yr, and expected to decrease due to increasing demand of water by other Nile basin countries. According to an Egyptian government report, the total population of Egypt increased from 22 million in 1950 to around 85 million in 2010. This increase in population will continue for decades and it is likely to increase to between 120-150 million by 2050. Egypt has reached a state where the quantity of water available is imposing limits on its national economic development.As indication of water scarcity, Egypt passed the international threshold value of 1000 m 3 /capita/year in the nineties, and it is expected to cross the threshold of absolute water scarcity of 500 m 3 /capita/yr by 2025. Capacitive deionization (CDI) is a relatively new technology that was developed as recently as the late 1960s. In CDI systems, saline water is made to pass between a pair of electrodes connected to a voltage source. Ions are stored inside the pores of electrodes in CDI via the applied electric field strength. CDI is a membrane less technology and the problems of membrane fouling in the Reverse Osmosis technology are not present in CDI. It has the potential to be energy efficient compared with other related techniques and robust technology for water desalination. This paper explores low cost and efficient desalination technologies for brackish water for irrigation and drinking purposes using the abundant solar energy in Egypt.

Performance Evaluation of a Solar-powered Membrane Capacitive Deionization System Considering Energy Recovery

“…The energy required to separate feeding salt water into the desalinated stream from the brine can be calculated using a thermodynamic technique (Długołecki and Van Der Wal 2013). Leading membrane-based desalination technologies like reverse osmosis (RO) and electrodialysis (ED) appear to not be viable alternatives, especially for brackish water desalination, because of their high power consumption (Seleym and Elshafei 2017). Theoretically, the minimum energy required to separate ions from a solution is around 3960 kJ/m 3 for seawater and 432 kJ/m 3 for brackish water, depending on the recovery and the input-output flow concentration ratio (Chen et al 2018).…”

Irrigation Management of Pepper Crop Under Surface and Sub-Surface Drip Irrigation Systems by Using Expert System, Irrimet and Cropwat

“…The total amount of available water in Egypt is 55.5 milliard m 3 /year and the sector of agriculture consumes about 85% of the total available water (Seleym and Elshafei, 2017). This amount of water may be decreased by 10% and 20% annually, reducing the national income of farmers by 32% to 33% per year (Gohar and Ward, 2013).…”