air blockingReading time:
The technique consists of partially drying the top layer of the resin bed, which then presents a high level of cohesion, greater than that obtained with water blocking.
All of the processes using this technique operate according to the following sequence :
- production cycle from top to bottom;
- regeneration from bottom to top.
Draining starts at the onset of the regeneration process once the dome of the unit is drained via eluate collection nozzles placed into the upper part of the resin bed. This process is maintained during injection and displacement of the regenerant by air being circulated through the dried layer. The eluate-air mixture is evacuated through the collection system. Air circulation can be obtained by the injection of compressed air or by suction using an external device such as an injector (figure 2).