Types of Hardness of Water:
Depending on the nature of dissolved salts in water. It is classified as –
- Temporary or Carbonate Hardness
- Permanent or Non-Carbonate Hardness
Temporary or Carbonate Hardness:
It is caused by the presence of dissolved bicarbonates of Ca, Mg, and Fe in water which can be removed by boiling or by treating water with slacked lime that is called Clark’s process.
Permanent or Non-Carbonate Hardness:
It is caused by the presence of dissolved chlorides and sulfates of Ca, Mg, and Fe. Permanent hardness can’t be removed by mere boiling or by adding lime to water.