Innovative disk thickener improves performance of digester at Chiquita Water Reclamation Facility in California.

Santa Margarita Water District's Chiquita Water Reclamation Facility has completed a process of upgrading their thickening process from a gravity thickener to allow improved performance of an under loaded digester. Feeding at a rate ranging from 0.4 − 0.8% DS the gravity thickener was only able to achieve a maximum result of 2.7% DS. The gravity thickening basin was converted to a thickened sludge basin and the selected mechanical thickener was placed on top of the basin. An evaluation of Gravity Belt Thickeners, Drum Thickeners, and the Disk Thickener was conducted. The Huber Technology RoS2S Disk Thickener was selected for implementation. After two years operation the plant reports that RoS2S Disk Thickener is consistently producing a 5.5% DS average with an ˜0.6% DS average feed at a steady flow of 107 gpm (60 gpm activated, 7 gpm trickling, 40 gpm service water) running 24 hours a day.