Here are the key steps in the base exchange process for removing permanent hardness from water:
1. Hard water passes through a column containing zeolite pellets or beads.
2. Zeolite is a sodium-based mineral that has the ability to exchange its sodium ions for calcium and magnesium ions from the hard water.
3. The calcium and magnesium ions from the hard water bond to the zeolite, replacing sodium. This removes the calcium and magnesium causing hardness.
4. The water leaving the column is softened as it no longer contains calcium and magnesium ions. It is replaced by sodium ions, which do not cause hardness.
5. Eventually the zeolite becomes saturated with calcium and magnesium