Sodium Zeolite Softening
Sodium Zeolite Softening
Introduction
Cation Exchanger Bead + + + +
+
-
-+ -+
+ + +
+
-+
+
+
-
-+ -+
+
-
+
+
-+
Ion exchange is the process in which materials exchange one ion for another, hold it temporarily, and release it to a regenerating solution. These materials are widely used to treat raw water supplies that contain dissolved salts. Today, the most commonly used material is an ion exchange resin. Resins are plastic beads to which a favorable ion has been chemically attached which can be exchanged for unwanted ions dissolved in the raw in the water supply. Once the resin has given up or exchanged most of its favorable ions, it is said to be exhausted and needs to be regenerated by coming in contact with a strong solution of ions called the regenerant.
Sodium zeolite softeners historical used natural zeolite materials but have now been replaced with exchange resins made of polystyrene. These resins have sodium ions loosely attached and will readily give up the sodium for a more desirable ion such as calcium and magnesium. This exchange is only for cations of positively charged ions. This is why sodium zeolite resin is referred to as a cation exchange resin. . The primary exchange reactions occurring at the surface of a sodium cation exchange resin are : 2RSO3-Na+ ⇔ (RSO3-)2Ca2+
+
Ca(HCO3)2
+
2Na(HCO3)2
Hardness Breakthrough at End of Softener Run
End of Run
...where "R" represents the solid resin. The water to be softened is passed through the vessel containing resin. Calcium and magnesium ions are exchanged for the sodium ions in and on the resin beads. The sodium then takes the place of the calcium and magnesium in associating with the anionic .
Na+
Effluent Level
TH
Volume Through Softener
Steam Generation Systems, Inc.
1108 Lavaca St., Suite 110-309 • Austin, Texas 78701 USA • 832-725-7662 •www.SteamGenerationSystems.com
Sodium Zeolite Softening
species in
Introduction
Cation Exchanger Bead + + + +
+
-
-+ -+
+ + +
+
-+
+
+
-
-+ -+
+
-
+
+
-+
Ion exchange is the process in which materials exchange one ion for another, hold it temporarily, and release it to a regenerating solution. These materials are widely used to treat raw water supplies that contain dissolved salts. Today, the most commonly used material is an ion exchange resin. Resins are plastic beads to which a favorable ion has been chemically attached which can be exchanged for unwanted ions dissolved in the raw in the water supply. Once the resin has given up or exchanged most of its favorable ions, it is said to be exhausted and needs to be regenerated by coming in contact with a strong solution of ions called the regenerant.
Sodium zeolite softeners historical used natural zeolite materials but have now been replaced with exchange resins made of polystyrene. These resins have sodium ions loosely attached and will readily give up the sodium for a more desirable ion such as calcium and magnesium. This exchange is only for cations of positively charged ions. This is why sodium zeolite resin is referred to as a cation exchange resin. . The primary exchange reactions occurring at the surface of a sodium cation exchange resin are : 2RSO3-Na+ ⇔ (RSO3-)2Ca2+
+
Ca(HCO3)2
+
2Na(HCO3)2
Hardness Breakthrough at End of Softener Run
End of Run
...where "R" represents the solid resin. The water to be softened is passed through the vessel containing resin. Calcium and magnesium ions are exchanged for the sodium ions in and on the resin beads. The sodium then takes the place of the calcium and magnesium in associating with the anionic .
Na+
Effluent Level
TH
Volume Through Softener
Steam Generation Systems, Inc.
1108 Lavaca St., Suite 110-309 • Austin, Texas 78701 USA • 832-725-7662 •www.SteamGenerationSystems.com
Sodium Zeolite Softening
species in