US Patent 7309436 Process for removing perchlorate ions from water streams

Methods and systems for removing perchiorate from water are disclosed which involve the use of a plurality of vessels containing an ion exchange resin having affinity for perchiorate ions, and in which perchiorate-contaminated water is passed over the resin in some but not all of the plurality of vessels operating in parallel to one another thereby removing perchlorate ion from the water stream and generating reduced perchlorate content product water streams and in which a subset of the plurality of vessels is removed from service, their resin is removed and replaced and they are returned to service.