Biological ion exchange capable of sulphate-based secondary ion exchange during long-term DOC removal.

Biological ion exchange (BIEX) offers removal of dissolved organic carbon (DOC) with greatly reduced regeneration frequency. In the present work, a strong base anionic exchange resin was operated without regeneration and using inlet water with either Low (12 mg L) or High (60 mg L) sulphate and DOC of 2.75 or 5.