Solar Ponds Utilization for Seawater Distillation

摘要

During this time natural sources of fresh water are limited in several countries. For this reason more than 2 billion people in the World still have no access to acceptable drinking water. Most of these countries are located in tropical and subtropical areas, with greater availability of renewable resources than advanced countries. Many of these countries are located along a sea-coast and have higher levels of solar energy. The most favorable belt (15-35° N) encompasses such countries in Northern Africa and Southern parts of Asia. Libya is one of the countries in Northern Africa situated along Mediterranean Sea shoreline, where seawater salinity is 39.5 x 103 (p.p.m.). Iraq and The Cooperation Council for the Arab States of the Gulf (GCC) are located along Arabian Gulf, where seawater salinity is 56 x 103 (p.p.m.) and Red Sea shorelines, where seawater salinity is 43 x 103 (p.p.m.). According to the standards for drinking water and other domestic uses, the accepted concentration of dissolved NaCl varies from 200 to 500 (p.p.m). The Arabian Gulf countries and Libya depen upon the desalination plants. The most common desalination processes used today is distillation. The thermal energy required for distillation processes can be obtained free from the Sun through the use of the salinity-gradient solar pond technologies. The cost of developing this technology in Iraq, (GCC) and Libya, which possesses abundant sunshine (solar energy) throughout the year, large amounts of salts, abundant saline water, wide area and several natural lakes, is usually much lower compared to that in advanced countries. In this paper the solar radiation conditions in Iraq, (GCC) and Libya, and the course of technology' advancement in solar pond have been analysed and studied. This paper summarizes the efforts wanted on solar pond development in these countries. This paper outlines the various technical problems that have to be solved during the construction and operation period of the solar pond and gives suggestions for future course of development