The hardness of water is mainly composed of cations: calcium (Ca2+) and magnesium (Mg2+). When raw water containing hardness passes through the resin layer of the exchanger, calcium and magnesium ions in the water are adsorbed by the resin, and sodium ions are released at the same time, so that the water flowing out of the exchanger is softened water without hardness ions. When the resin adsorbs calcium and magnesium ions to a certain saturation, the hardness of the effluent increases. At this time, the water softener will automatically regenerate the failed resin according to the predetermined procedure, and use a higher concentration of sodium chloride solution (brine) to restore the failed resin to sodium resin.
Advantages of industrial salt: 1. The price of industrial salt is lower than that of ordinary salt. 2. Because the regeneration needs saturated brine, there must be salt particles in the water. Ordinary salt particles are very small and easy to be inhaled into the controller, thus causing damage to the controller.