water blockingReading time:
Historically, water blocking was the first process used.
The regenerant solution is injected at the base of the ion exchanger resin bed; while a stream of blocking water is introduced at the top of the unit. The fluids flow through the sampling outlets in the upper section of the resin bed (figure 1).
Regeneration balances show that this method can provide treated water with satisfactory quality if the upflow velocity is maintained between 2 and 2.5 m·h–1. However, the amounts of reagents used remain high.
Today, this process is practically no longer in use, due to the development of new processes, with higher performance as described in the following.