Desalination and extraction of salt from sea water based on solar energy

The ongoing water crisis and the attempts to preserve the uniqueness of the Dead Sea prompted the current proposal for desalination and extraction of salt from sea water based on use of solar energy. A plant using the proposed technology has no harmful impact on either environment or the interests of neighboring countries. In addition, it allows creation of a hydroelectric power plant with the capacity proportional to the surface of the salt gradient solar pond.

The proposal deals with an industrial reconstruction of the Dead Sea area, as opposed to "preservation of its uniqueness." All the proposals considered today aim at preserving the level of the Dead Sea with the help of a channel with a water capacity sufficient to compensate for the river water used for agricultural needs. All these projects are seriously flawed and cannot be implemented today for the following reasons:

The exorbitant cost of such a project (about $5B) and planned construction time (10 years); under present circumstances the debates involved will delay the implementation of such a project by another 40 years.

These projects don't restore the native environment of the Dead Sea because they involve dumping about 50M tons of minerals foreign by composition into the sea yearly. The mineral and thermal structure of the Dead Sea is heterogeneous and therefore non-resistant to changes in the mineral composition, which could result in unpredictable consequences (beneficial or perilous). There is no definitive scientific prognosis to that effect. Once such a project is implemented, its consequences are irreversible! 

The essence of the current proposal is a stage-based, modular development of the Dead Sea area based on its topography and waters of the external sea (as opposed to the waters of the Dead Sea proper). The technology is based on the Israeli patent #67054. Financial risks (the cost of a pilot installation) amount to $250,000.

Thermodynamic calculation shows that a salt gradient solar pond with a surface of 0.3 sq. km can produce 1M m³ of desalinated water yearly.

Its technical specifications are:

• Feed water from Mediterranean: 2.4M m³/year
• Water consumption:
• Evaporation: 1.08M m³/year
• Condensation in the Flash Evaporator: 1.08M m³/year
• Reject brine: 240M m³/year at the 36% concentration
• Total power output: 2 GW-h/year, half of it marketable
• Connection between terminals: standard 16'' - 18'' pipe.

After a successful exploitation of the pilot installation, the total surface of the salt gradient solar pond can be increased to 80 sq. km. This will enable processing 0.58 km3/year of external sea water to produce 244 GW-h/year of electric power and 244M m3/year of desalinated water (24% of total agricultural consumption) without any harmful environmental impact. In addition, it will produce 0.059 km3/year of 36% mineral brine (including 15M tons table salt, world consumption being 225M tons).