 The air blanket was formed by recycling water saturated with compressed air injected through a ‘Thames DAF nozzle’ located at about half of the vessels height.The pilot plant was successful and a full scale 200 Ml/day plant was constructed in the late 1990s at Walton Advanced Water Treatment Works using the CoCoDAFF system.After treatment in the CoCoDAFF water passes through post-ozone and granular activated carbon (GAC) contactors then through slow sand filters before disinfection where sodium hypochlorite is introduced to contact tanks.