Dr. Caliskaner was the principal investigator and project manager of this advanced primary treatment (APT) and carbon diversion technology development project funded by the California Energy Commission. The project had seven different sponsors from industry, academia, and public utilities. The project included testing of five wastewater filters for 2 years (between 2013-2015) to demonstrate significant potential energy and capital savings at water resource recovery facilities (WRRF). This project was significant as the first full scale demonstration for continuous operation of filtration systems as APT technologies. Design and operational principles were established for primary effluent filtration (PEF). The demonstration system consisted of the five wastewater filters:
- Cloth Disk Filter™ (CDF): Manufactured by Aqua-Aerobic Systems, Inc. The CDF used for this project was an Aqua MiniDisk® that used an OptiFiber® pile cloth filtration medium.
- Fuzzy Filter™: Manufactured by Schreiber LLC. The Fuzzy Filter is a compressible media filter type that provides operational flexibility to change the filter medium compression between 0 and 40% to alter the filter media characteristics in response to changing influent wastewater conditions.
- FlexFilter™: Manufactured by WesTech Engineering, Inc. The FlexFilter uses synthetic fiber compressible media (nominal 2” diameter) compressed lateral by an engineered fabric using the hydraulic force applied by the influent head.
- SuperDisc™: Manufactured by WesTech Engineering, Inc. The SuperDisc utilizes a polyester disk filter medium with a defined pore size.
- Ultra Screen Filter™: Manufactured by Nova Water Technologies. The ultra screen filter used for this project is a disk filter that uses continuously rotating stainless steel mesh as the filtration medium.
Following benefits were estimated based on the process modeling using treatment and hydraulic performance results obtained during the PEF demonstration project at the Linda County Water District’s (Linda) WRRF.
- PEF reduces secondary process actual oxygen requirement (AOR) by diverting biological oxygen demand (BOD) from the secondary process to the anaerobic digester. AOR and blower airflow at Linda WRRF was estimated to be reduced by approximately 15 and 30%, respectively.
- PEF increases digester gas flow by diverting additional volatile suspended solids to anaerobic digestion. Digester gas at Linda WRRF was estimated to be increased approximately 35%.
- PEF increases secondary process capacity by diverting total suspended solids and BOD from the secondary process. Secondary process treatment capacity at Linda County Water District WWTP was estimated to be increased by approximately 30%.