The salt or potassium chloride is a sacrificial media and must be replenished on a regular basis to ensure adequate softening form the device. The following equilibrium reaction describes the dissolving/formation of calcium carbonate scales: Calcium and magnesium ions can be easily removed by the ion exchange process. Our editors will review what you’ve submitted and determine whether to revise the article. At first, the exchangers used for this purpose were natural aluminosilicates, but later, synthetic resins came to be used instead. To convert between gpg and ppm use the following factor; 1 gpg = 17.1 ppm. People on restricted sodium intake diets should account for increased levels of sodium in softened water. The heart of the softener is the mineral tank which is a pressure vessel usually constructed out of fiberglass. When it is equipped with two mineral tanks, softened water is always available, even when the unit is recharging. The presence of certain metal ions like calcium and magnesium principally as bicarbonates, chlorides, and sulfates in water causes a variety of problems. Multivalent cations are cations (metal ions) with a charge greater than 1+, mainly 2+. A common magnesium mineral is dolomite which also contains calcium. You can live with the hardness level, recognizing that levels below 7.0 gpg will probably not cause major scaling and soap film, or treat the water to reduce the calcium and magnesium present.A water softener, also called an ion exchange unit, will effectively accomplish the latter option. Omissions? The lime-soda method of water softening must be followed by sedimentation and filtration in order to remove the precipitates. This process of trapping of ions happens with a simultaneous releasing of other ions resulting in the term ion-exchange. When enough water has passed through the mineral tank to have depleted the beads of sodium, the computer triggers regeneration. What this essentially does is take the cations of calcium and magnesium (the two most common causes of hard water) and replace them with the cations of another substance. The brine tank is basically a storage tank for sodium chloride (NaCl) or potassium chloride (KCL) which is mixed with water during the brine refill and regeneration cycles. A softener is comprised of different components, each having their own unique purpose. Parts per million is defined as one milligram of calcium carbonate (CaCO3) per litre of water. Water softening, the process of removing the dissolved calcium and magnesium salts that cause hardness in water. Hardness is measured by the level of calcium and magnesium bicarbonates in water and together represent Total Hardness (TH). Hard water is any type of water that contains more minerals than average tap water. For every grain of hardness removed from water, 8 mg/1 (ppm) of sodium is added. These softeners often have reserve resin capacity, so that some soft water will be available during recharging. Hard water can be problematic because the calcium and magnesium ions react with the higher fatty acids of soap to form an insoluble gelatinous curd, thereby causing a waste of the soap (this objectionable reaction does not take place with modern detergents). A second type of control uses a computer that watches how much water is used. Updates? By doing this, the water softening removes the offending minerals from the water. Hard water flows through the resin beads; Sodium is swapped for hard water minerals; Did You Know? Hardness can be quantified by instrumental analysis. Let us know if you have suggestions to improve this article (requires login). During the regeneration cycle, brine (brackish water created in the brine tank by mixing water and salt) is passed through the resin tank (either up or down depending on the design). Hard water is generally not harmful to one's health but can pose serious plumbing problems in both residential and commercial applications. It is these ions in hard water that make it difficult for products with other positively charged ions to dissolve in the water. Softening is the process of removing the dissolved calcium and magnesium salts that cause hardness in water.