Hard water typically has a hardness concentration over 120 mg/L CaCO3. Hardness is not a regulated drinking water parameter and does not have severe health effects. However, hard water causes more soap and detergent consumption and can cause scaling problems on household heating appliances, distribution pipes, and industrial cooling equipment. There are various approaches to soften hard water or prevent scale formation at the centralized and the household scale. In order to choose the best treatment for a specific set of conditions, an appropriate technology evaluation is necessary. Prior research have tested single technology or compared two or three technologies with respect to their performance. Not many papers have compared all available technologies using the same assessment criteria. At the household scale, point-of-entry (POE) devices are commonly used. Among these, ion exchange is the most widely applied POE device in Canada, though it has two major disadvantages: high sodium concentration in softened water and high chloride content in the brine which is often discharged into the sewer. Hence, there is an increasing interest in adopting salt-free treatment technology. Template assisted crystallization (TAC) is a relatively new household scale prevention technology. TAC media transforms free calcium (Ca2+) and magnesium (Mg2+) ions into insoluble microcrystals. TAC technology has the potential to be an alternative to ion exchange, but there is very little published journals about this technology.
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Djalilov, Jasur Abdukhalilovich
"SOFTENING OF DRINKING WATER IN A DEVICE BASED ON HIGH-FREQUENCY DIODES,"
Mental Enlightenment Scientific-Methodological Journal: Vol. 2022:
3, Article 16.
Available at: https://uzjournals.edu.uz/tziuj/vol2022/iss3/16