THE MANUFACTURING PROCESS OF HIGH HARDNESS DRINKING WATER USING NF/RO/ED MEMBRANE CONNECTION SYSTEM

摘要

The present invention relates to a mineral water quality control technology which removes sulfate ions and chloride ions and allows useful minerals such as magnesium, calcium or the like to be remained during a seawater (raw or concentrated deep seawater) desalination process and, more specifically, to a process connection system development for optimum water quality adjustment in a seawater desalination process comprising: a step of adjusting selected minerals using a complex method of electrodialysis (ED), nano-filtration (NF) and reverse osmosis (RO) systems in a seawater (deep seawater) desalination process; and a step of removing specific materials using electrodialysis (ED) and nano-filtration (NF). The ERO/NF/ED or NF/ED connection process relates to a process for simultaneously manufacturing deep seawater treatment water containing demineralised water, concentrated water, mineral desalinated water, mineral concentrated water and salty water and is capable of saving energy compared to a technology including a conventional evaporation method, mass-producing deep seawater treatment water and manufacturing mineral concentrated water by removing sulfate ions and chloride ions. By adjusting the pH of alkaline water produced by controlling the current of an electrolysis tank from 10 to 13, a calcium carbonate deposit is formed at pH 10 and a magnesium hydrate is produced and precipitated at pH 13. Therefore, high hardness water suitable for drinking water quality standards can be produced as calcium and magnesium mineral extracts can be separately extracted, thereby reducing the energy consumption of the process.