Unlocking Energy Savings through Strategic Process Intensification of WRRFs

Presentation Description: This technology research and development project (EPC-20-044) funded by California Energy Commission (CEC) evaluates the energy savings potential of advanced primary treatment (APT) and advanced secondary treatment (AST) technologies in reducing biological aeration demands and increasing energy recovery at Water Resource Recovery Facilities (WRRF). Over a three-year demonstration period conducted at the Linda County Water District’s (Linda) WRRF, six technologies were assessed for energy and intensification performances: Cloth Disk Primary Filter (CDPF), Proteus Filter (Proteus), and Micro-Screen (MS) for APT; and MicroNiche Engineering (MicroVi), Membrane Aerated Biofilm Reactor (MABR), and Aerobic Granular Sludge (AGS) for AST.
In the demonstration, the primary clarifier served as the baseline for primary treatment, with flow distributed parallelly to the three APT systems. For secondary treatment, conventional aeration basins processed flow from both the primary clarifier and APT units, while a portion was diverted to the AST units. All systems operated concurrently in parallel.
Measured energy and SCADA data revealed that all APT technologies significantly reduced aeration demand under full-scale scenarios. Under similar organic and nutrient loading, projected energy savings from APT (i.e., Primary Filtration technologies) ranged from approximately 25% to 30%.
AST technologies also demonstrated strong energy-savings potential, achieving approximately 20% to 40% reductions in aeration energy demand compared to conventional secondary treatment. These savings were attributed to enhanced process kinetics and reduced oxygen transfer requirements.
The findings support the integration of APT and AST technologies as a viable pathway for energy optimization in WRRFs. Full-scale implementation, coupled with responsive control systems and plantwide energy modeling (i.e., using modeling tools such as SUMO), could significantly advance operational sustainability and reduce energy intensity in wastewater treatment.