THE COMING WATER CRISIS AND DESALINATION SOLUTIONS

Fresh water suitable for human consumption, industrial, and agricultural uses is in increasingly short supply in the world today. In arid and semi-arid regions, in both industrialized and developing countries, the problem is the same: available fresh water supplies are near or beyond their natural limits. In many regions, serious degradation of the environment related to excessive extraction of water from surface and ground waters is already all too common. Over-pumped groundwater resources are being degraded or exhausted. Increased pollution has followed disruption of the natural hydrological balance.

Water shortages are also political flashpoints that are likely to be the cause of conflict, for instance between California, Nevada, Arizona, and other States drawing water from the Colorado River, and war, such as is likely in the Middle East and North Africa between many countries sharing limited water sources.

Production of new fresh water supplies by desalination of seawater has the potential to alleviate many of these water shortages, but desalination is presently expensive, especially where water contains suspended sediments and man-made pollutants such as petroleum products, which must first be removed. Nonetheless, where no new fresh water supplies are available, desalination is the only viable answer to the problem of increasing water supplies.

Each desalination technology extracts fresh water in a different way and each method has a particular range of naturally occurring physical, chemical, and thermodynamic constraints and costs. These conventional desalination technologies are now relatively mature, having been introduced many years ago and improved greatly over time. Improving the efficiencies of the existing methods of desalination has thus become a matter of fine-scale adjustment. Dramatic improvement in raising the volumes of water produced or in lowering the costs of desalination is only possible by introducing new technology, which brings with it a new range of physical and cost factors.

Click here to view "Rivers From the Sea" an animated presentation of the MDS carbon dioxide desalination process.