Ion exchange technology is routinely utilized for partial or complete demineralization of the water supply, softening, and dealkalization, or it can be customized for selective removal of a specific contaminant (for example, denitratization). In simplest terms, ion exchange involves using a selective resin to exchange a less desirable ion with a more desirable ion.
The process of “dealkalization” can soften water. Dealkalization reduces the salinity of the water, by eliminating hardness cations and bicarbonate anions.
Water is passed through a bed of weakly acidic resin, and the calcium and magnesium ions are replaced by hydrogen ions. The hydrogen ions react with the carbonate and bicarbonate ions to produce carbon dioxide. The hardness of the water is thus reduced without any increase in sodium levels.
It also provides some degree of total dissolved solids (TDS) removal. Generally, weak acid cation resin removes about 80 percent of the temporary hardness (hardness associated with dissolved bicarbonate minerals). Total dissolved solids (TDS) are reduced by about 17.1 parts per million (ppm) for each grain of hardness removed.
Dealkalization process
