Calcium and magnesium are removed by which external water treatment process that can be regenerated using sodium chloride?

The correct answer is the zeolite softener, which is a type of ion exchange process specifically designed for water softening. This process primarily targets the removal of hardness-causing minerals, such as calcium and magnesium, from water.

The zeolite material works by exchanging sodium ions for calcium and magnesium ions in the water. As the water passes through the zeolite medium, the hardness ions are effectively removed, thus softening the water. After a certain period of use, the zeolite becomes saturated with calcium and magnesium ions, at which point it can be regenerated. This regeneration process involves flushing the saturated zeolite with a sodium chloride (table salt) solution. The high concentration of sodium ions in the brine solution displaces the calcium and magnesium ions, allowing the zeolite to be reused for further softening.

This mechanism is crucial for maintaining operational efficiency in boiler systems, as hard water can lead to scale formation and damage to equipment. Understanding the function of zeolite softeners is essential for those involved in boiler maintenance and operation, especially in contexts where water quality is critical to performance and longevity.

While ion exchange also involves the exchange of ions to remove impurities from water, the specific mention of regeneration with sodium chloride aligns more closely with the ze