The Actina™ process is based on the pellet softening principle, which consists in modifying the calcium-carbon equilibrium of water to be treated by soda or lime injection, and to cause calcium carbonate crystallization on sand.
This unique injection system was patented by Veolia.
Actina™ is composed of a vertical reactor in which a bed of sand is maintained in fluidization by pumping the water to be softened. This very fine sand is used as a crystallization seed for the pellet softening reaction, that is to say calcium carbonate precipitation on the surface of grains of sand. The highly basic pH enabling crystallization is obtained by alkaline reagent (soda or lime) addition at the reactor base.
The calcium carbonate thereby removed occurs as beads of a few millimeters in diameter, easily storable, transportable and recoverable.
The use of a fluidized bed allows Actina™ to run with high rising rates, around 80 to 100 m/h and confers it a small footprint.