Technical and mineral level effects of water treatment

Reverse Osmosis is used for desalination of especially sea water in areas suffering from water shortage, and there are thousands and thousands of desalination plants around the world and more to come. The produced high–purity water tends to be corrosive, and lacks minerals, causing decreased daily intake and loss of minerals from the body. Thus, such water needs re–mineralization. Water with toxic substances is harmful, and is also often treated with RO. There are indexes to be used as guides to choose re–mineralization method after RO. However, mineral balance is not reached by remineralization, as only concentrations of calcium and bicarbonate, and in some cases magnesium is increased. Treatment with dissolution of dolomitic–calcitic limestone or other limestone with low levels of toxic elements is preferable. Hard water, on the other hand, may cause scaling, and is often softened, making the concentrations of calcium and magnesium low or extremely low. General advices on choice of treatment method to preserve or improve the mineral content and mineral balance of a water is presented in the chapter.