A
treatment system passes feed water containing a contaminant such as
perchlorate through a
bed of strong base anion exchange resin that has been placed in a form (e.g., in
sulfate form) to selectively capture the contaminant while passing other ions (e.g.,
nitrate) that may also be present in the water. The
bed selectively removes the
perchlorate with high efficiency, for example on a stoichiometric basis, until exhaustion. The
bed operates robustly without spiking or displacement of more weakly-held or
lower affinity ions as composition of the feed varies. The water may be further treated, if necessary, to produce a purified or potable product, in which case downstream processes may remove remaining contaminants and co-ions. Alternatively, the treated
stream may be returned to or blended with the source to effect contaminant remediation, e.g., site clean-up. Contaminants such as
uranium species,
perchlorate or pertechnate may be treated by this method using ordinary (non-
specialty) exchange resins. The bed may include a carousel, and the exhausted upstream portion of the resin may efficiently be disposed of by
incineration, or may be rotated out for regeneration. Alternatively, the bed or the spent portion thereof may be periodically regenerated transferring perchlorate to a regeneration fluid waste. The concentrated waste may be disposed of by
incineration, bioreaction or other suitable disposal process. The concentrated regen waste may also be passed through a smaller, sacrificial bed of
ion exchange resin to capture its perchlorate, allowing re-use of the regen fluid and forming a lower-volume
solid waste output. This second-bed re-transfer process operates efficiently at the
high concentration present in spent regen fluid, and requires only a small fraction of the original bed volume.