Single-Bed Demineralizers:

A single-bed demineralizer holds either cation or anion resin beads. In many cases, there are two, single-bed ion exchangers in series; a first is a cation bed and the second is an anion bed. Impurities within plant water are exchanged along with hydrogen ions within the cation bed and hydroxyl ions inside the anion bed. Hydrogen ions and the hydroxyl ions then merge to form pure water.

Figure describes a single-bed demineralizer. While in use, water flows in by the inlet to a distributor at the top of the tank. The water flows down by the resin bed and exits out by the outlet. A support screen at the bottom avoids the resin from being forced out of the demineralizer tank.

Figure: Single-Bed Demineralizer