What is the common term for the method used to remove hardness from water?

The common term for the method used to remove hardness from water is known as water softening. This process typically involves the exchange of calcium and magnesium ions, which contribute to hardness, with sodium or potassium ions. The primary method for water softening is ion exchange, where a softening resin captures the harder ions in exchange for softer ones. This results in water that has reduced hardness levels, making it more suitable for applications like laundry, dishwashing, and preventing scale buildup in pipes and appliances.

Filtration generally pertains to the removal of particulate matter and is not specifically aimed at addressing hardness. Hardness extraction is not a widely recognized term in water treatment and does not effectively describe the established processes used for softening water. Coagulation is a process primarily used to remove suspended solids and is not focused on hardness removal either. Consequently, water softening is the correct term that encompasses the specific method used to tackle water hardness effectively.