DIVISION OF MAGNA-TEK SYSTEMS, OAKVILLE, ONTARIO
A water softener uses a medium that serves to exchange "ions" of calcium and magnesium with sodium and potassium.
This occurs in four steps:
1. To do the ion replacement, the water in the house runs through a resin bed of small plastic beads or zeolite. The beads are covered with sodium or potassium ions. As the water flows past the ions, they swap places with the calcium and magnesium ions. Eventually, the beads contain nothing but calcium and magnesium, and softening stops. It is then time to regenerate the beads or zeolite.
2. To regenerate, the beads need to regain their sodium or potassium ions by being flooded with a salty, brine solution that is rich in sodium or potassium.
3. Once completed, the calcium and magnesium, dirt and sediments are flushed from the beads and into the drain in a process called backwash.
4. The final phase rinses the mineral tank with fresh water and loads the brine tank so it's ready for the next cycle.
During the softening process sodium is released from the exchange media into the output water. For every grain of hardness removed from water, 8 mg/1 (ppm) of sodium is added. People on restricted sodium intake diets should account for increased levels of sodium in softened water.