EFFECT OF FILTER MEDIA ON CYST AND OOCYST REMOVAL

摘要

As part of a pilot-scale examination of filtration media at the Cincinnati (Ohio)Water Works, heat-inactivated Giardia cysts and Cryptosporidium oocysts were spiked into surface water that had already undergone coagulation and sedimentation. This spiked water was then introduced into pilot-scale filters containing sand only,typical dual anthracite-sand, deep dual anthracite-sand media configurations. All of the media types used in this study demonstrated similar removal capabilities, with average cyst removal ranging from 2.7 to > 4.5 logs and average oocyst removal of 2.7-3.9 logs. Endospore and polystyrene bead removals were similar to those of the protozoa, but turbidity and particle counts demonstrated substantially less removal capability.