On application of freshwater water supply business derived from deep ocean water

Abstract

Application of desalination technology for deep ocean water (hereinafter, DOW) to the tap water supply business has been verified. DOW is advantageous for desalination because it has less suspended solids and less chlorine consumption than surface seawater (hereinafter, SOW). In addition, the amount of DOW is huge compared to the water available on land (river water, lake water, etc.) used in most of the current tap water systems. In addition, the water temperature and quality of DOW are stable, and its water quality is extremely clean as well as no restriction of water rights for using. Possible disadvantages are locations where DOW can be taken are generally far from urban areas, which are large-scale consumption areas, and the cost of desalination of DOW is higher than that of current tap water cleaning process using river and reservoir waters. However, the cost difference is narrowing with the progress of technology, and it is presumed that the cost will be further reduced if freshwater production is used as a by-product of ocean thermal energy conversion. Accordingly, it is considered that DOW desalination technology can greatly contribute to solving various problems of water treatments in the current tap water supply business.