Abstract
Serious troubles regarding scale formation may occur when the amount of recovered water from sea water increases. The main constituents of the scale are CaCO3, Mg(OH)2, CaSO4 and so on, all of which are salts of alkaline earth metals. Therefore, if a key technology is developed with which the main constituents of the scale, alkaline earth metal ions such as CaCO3, Mg(OH)2, CaSO4 and so on, can be removed and/or separated from sea water the recovery of desalted water from raw sea water using high-pressure reverse osmosis (HPRO) can be increased up to 75-80%, the solubility limit of the remaining scale components. Then it will be possible to make use of all valuable materials that exist in sea water, using an integrated system that combines conventional recovery technologies with a set of the proposed technologies such as HPRO, an alkaline earth metal ions removal process, inorganic ion exchangers for recovering trace elements and so on. Furthermore, almost complete utilization of sea water may be accomplished by using of the brackish water by product for salt-resistant plants such as mangrove, salt bush and, if possible, gene-recombinated plants.
