The recovery boiler at SCA Obbola has high operating data of 110 bar/505°C. This requires a very high purity level in the feed water. Both waste water and steam concentrate must be treated to a conductivity of <0.1 µS/cm, Na content <10 ppb and silica acid content < 20 ppb.
The treatment process consists of preliminary treatment, continuous sand filtration, desalination, two parallel ion filter lines, cation filter, anion filter, condensate treatment, precoat filter, final treatment of desalinated water and treated condensate.