Patent ID: 6290847
Filing Date: 2001-09-18
Classification: B01D,B01J,C02F

Abstract:
A replaceable gravity-flow cyst-reducing water filtration cartridge, comprising:a filter cartridge housing having a top rim, a side surface and a bottom rim, said top rim being adapted for attachment to an untreated water reservoir receptacle of a water carafe, said bottom rim being in fluid communication with a treated reservoir of said water carafe, said filter housing, further comprising:a compressed bed of ion-exchange resin disposed within an upper region and proximate to said top rim of said filter housing, said compressed bed of ion-exchange resin being bounded at the top with a top screen and being bounded at the bottom with a bottom screen, each of said top screen and said bottom screen being in full contact with said compressed bed of ion-exchange resin;a high surface area cyst-reducing filter element disposed within a lower region and proximate to said bottom rim of said filter housing, said cyst-reducing filter element providing at least 99.95% removal of 3-4 .mu.m particles when tested in accordance with NSF standard 53, Drinking Water Treatment Units--Health Effects (September 1997);a middle chamber separating said compressed bed of ion-exchange resin from said cyst-reducing filter element; andat least one hydrophobic air vent conduit connected to said lower region of said filter housing, said hydrophobic air vent conduit having an entry end and an exit end, said entry end being positioned above a topmost surface of said cyst-reducing filter element, said exit end being positioned at least at a lowest surface of said cyst-reducing filter element;wherein said compressed bed of ion-exchange resin occupies at least 95% of a non-interstitial space between said top screen and said bottom screen of said filter housing.