PHASED TEMPERATURE ANAEROBIC DIGESTION AT JEFFERSON COUNTY ALABAMA'S 60 MGD VILLAGE CREEK WWTP PRODUCES CLASS “A” BIOSOLIDS

In August 2000, Jefferson County Environmental Services Department placed in operation the largest known installation of the Phased Temperature Anaerobic Digestion process at the 60 MGD Village Creek WWTP in Birmingham, Alabama. Village Creek is a two-stage activated sludge plant with primary clarifiers and a future peak flow treatment facility. Up to 75,000 lbs/day of primary solids and 75,000 lbs/day of thickened waste biological solids are produced in the plant and are now digested and dewatered at up to 30% dry solids for disposal in the County's beneficial land application program. This paper presents the design parameters and initial operations data and how this process compares with the Class A pathogen reduction requirements (40 CFR Part 503).