Master Planning for Advanced Nutrient Removal
Greeley and Hansen, A TYLin Company, conceptualized and led a 20-year master plan for facility-wide upgrades to convert the 16 MGD wastewater treatment plant for Thorn Creek Basin Sanitary District to meet advanced nutrient removal requirements.
The master planning effort provided the opportunity to repurpose existing unused tankage that once comprised the first stage of a two-stage activated sludge plant. This included the conversion of existing off-line secondary clarifiers to secondary anoxic zones as part of a 4-stage Bardenpho Process. By utilizing existing facilities in the upgrade, reliable compliance with impending nutrient removal requirements were estimated to cost approximately 40% less than the District’s baseline budgetary allocation.
The chosen alternative provided substantial cost savings by applying the innovative concept of linking out of service secondary process tanks into a single stage process by adaptive reuse of the old secondary clarifiers as secondary anoxic zones. This innovation eliminated the need for tertiary denitrification.
Project Highlights:
- Implementation of a comprehensive wastewater characterization sampling program involving both long-term and short-term dynamic diurnal sampling events.
- Development of a dynamic process model for current baseline conditions, as well as nine distinct process modification and addition alternative.
- Analysis of life cycle, capital and operating costs to determine most advantageous process modifications, including considerations for phased implementation as additional permit conditions are imposed.