Presented by: Dr. Doug Borgatti, PE
A 67-MGD regional activated sludge wastewater treatment facility (SRWTF) is located on Bondi Island in Agawam, Massachusetts and operated by the Springfield Water and Sewer Commission (SWSC). As part of their Biosolids Management Program, the SWSC is decreasing the production of secondary sludge at the SRWTF. The first method of minimizing secondary sludge was to increase the solids retention time (SRT) from four to eighteen days. The SRT was increased by increasing the mixed liquor suspended solids from 2,000 to 5,000 mg/L. This change yielded a 30 percent decrease in sludge production and reduced costs for sludge processing, polymer usage, electricity and labor.
A second method of sludge reduction, a KADY Biolysis System (BLS), was also investigated for a period of 1 year. The BLS is touted by KADY as a process that reduces sludge volume by rupturing microbial cell membranes through cavitations pressures created by their mills. In Dr. Borgatti's talk, he will compare the KADY process to the increased SRT method and estimate any additional decrease in the production of sludge with the KADY system. In addition, he will discuss the settlings and solids management in the final clarifiers and the power requirements for aeration associated with the KADY process. Also, Dr. Borgatti will present an evaluation of the effects of the KADY process on sludge thickening and dewatering, as well as a cost analysis.