Recent developments in water desalination

The paper presents a global overview of the desalination of seawater. Lessons learned from success stories in the field are critically examined to indicate the potential of these initiatives to be treated as best practice initiatives for their possible applications in Mediterranean countries. Results from some interesting case studies elsewhere and from Libya are briefly given. An example from studies initiated at the Tajoura Engineering Academy indicating solar distillation as a promising alternative for saline water distillation that can partially support needs for fresh water with free energy, simple technology and a clean environment particularly in remote/rural communities are discussed. A plan to ensure the availability of high-quality water in coastal areas is presented to seek venues of possible cooperation amongst potential interested agencies in Mediterranean countries.

The paper has presented an overview of water desalination in coastal areas. It has identified numerous difficulties in promoting the utilization and development of seawater desalination technologies. The review of best practice initiatives shows that currently there are three major distillation processes, MSF, MED and VC, which are in use commercially. MED technology is facing decline, mainly because of operation and maintenance problems due to scaling and fouling, especially at high-temperature operation. MSF plants provide the bulk of the installed capacity. VC small plants are also in operation. In addition, major membrane desalination processes such as RO, EDR and membrane softening are gaining popularity. However, RO is not generally favoured, especially in locations which have high temperatures up to 40°C, high salinity levels, high silt density, high bacteria activity and high pollution, since these require complex pretreatment. Solar distillation has the potential to become a promising alternative for saline water distillation that can partially support needs for fresh water with free energy, simple technology and a clean environment, particularly in remote/ rural communities. Dealing with uncertainty and risk in the water industry needs not only a concerted plan of action but also a daring, caring and sharing approach. Daring without knowledge is risky. Knowledge without daring is fruitless. There is a vital need to develop new water policys outlining measures to bridge the gap between current policies and those that lead to the sustainable use of the world’s water resources. It is recommended that the Mediterranean countries pay new attention to areas including (1) institutional development, reforms and restructuring of water and energy industry and sector planning; (2) the development of greater community awareness and participation including the increase involvement of women; (3) the development and utilization of affordable appropriate technologies for water desalination; (4) research on issues related to sustainable water resources including scientific and engineering concerns on water quantity and quality, water supply and demand, geology, pollution sources, integration of water supply with sanitation and hygiene education; etc; (5) the importance of adequate operation and maintenance of systems; (6) the conservation and efficiency issues in water use; (7) the mobilization of communities through the eco-village movement concept to manage their programs through demonstration and extension services including the development of own cost recovery measures for operation and maintenance; (8) the significance of human resources development through awareness among policymakers, quality education , training and life-long learning; (9) promote and support studies and research and enhanced public understanding specially in the field of water supply using renewable energy like solar stills in remote/rural areas as a strategic priority; and (10) cooperation on water management and demand management practices at region-wide levels.