Brief Project Description
The Town of Farmville owns and operates the Farmville Waste Water Treatment Plant which has a permitted capacity of 2.4 MGD and discharges to the Appomattox River. The existing plant is a dual basin Biolac activated sludge treatment process with integral clarifiers and tertiary (up-flow) sand filtration. The plant was not designed to remove nitrogen or phosphorus.
Under the proposal for nutrient removal cost share, retrofit of the existing Biolac activated sludge process will be accomplished by installing the Parkson Wave Oxidation process for nitrogen removal. The wave oxidation process promotes denitrification by opening and closing the air valves to create anoxic zones in the Biolac lagoon basin. Phosphorus will be removed by the addition a metal salts prior to effluent filtration by the existing Dynasand up-flow effluent filtration. A metal salt addition and feed system will be installed. The enhanced nutrient removal (ENR) upgrade project will include the following:
- Installation of electrically actuated butterfly valves on each aeration chain
- Installation of nitrified liquor recycle pumps and piping
- Installation of dissolved oxygen (DO) probes
- Installation of an electrical control panel to operate the new butterfly valves in response to DO levels
- Upgrade of air flow measurement sensors on the existing blower discharge to provide better control of the blowers
- Installation of new diffuser assemblies in the Biolac basins to provide adequate air flow
- Installation of bulk storage, day tank, metering pumps and secondary containment for metal salt addition