A water softening system is usually used to remove hard minerals from the water supply system of a house. This is because hard minerals in water cause the water to be unfit for usage as it disrupts many household functions. A water softening system is mainly attached to the water supply system of the house, their main function is to exchange the positively charged ions of calcium and magnesium (which make the water hard), with other ions, mostly sodium. This process of trading ions from water is known as ion exchange.
When hard water passes through the water softening system which contains sodium, the positively charged ions of calcium and magnesium attach themselves to the beads inside the system, being replaced by positively charged sodium ions. So the water enters the system as hard water and leaves the system containing sodium ions which make it soft water.
For the sodium ions, there are different types of salts that are used in the water softening system. Rock Salt is one of them, it contains a sodium chloride concentration of about ninety eight to ninety nine percent. It is cheaper than the rest of the salts in the market but requires more frequent cleaning of the softening reservoirs in the water softening system, as it contains, in comparison, more non-water soluble substances in it. Secondly, we have solar salt which is a naturally produced salt. It is obtained by evaporation of seawater. It has a sodium chloride concentration of about eighty five percent and is usually sold in the form of a crystal. Lastly, we have evaporated salt, which is found through mining of salt deposits of dissolving salts and then evaporated until we have a salt form. The sodium chloride concentration it contains is about 99.6 to 99.99 percent. To know more about the mechanics of water softening systems, check the full post.