Case Study – Virginia, MN
The Virginia, Minnesota wastewater treatment facility went through an upgrade which was completed in 2013 at a cost of $18.5 million dollars. Its design average daily flow is 3.1 MGD, 30 day wet weather flow is 4.3 MGD and peak hourly wet weather flow at 9.9 MGD.
The treatment process includes flow measurement, screening, raw sewage pumping, vortex grit removal, flow retention primary clarification, biological treatment (conventional activated sludge) final clarification, effluent filtration (dual media gravity for reduction of mercury), effluent disinfection (ultra violet light), chemical phosphorous reduction primary and secondary anaerobic digestion, bio-solids dewatering (belt filter press) bio-solid storage (concrete walled bituminous pad with partial membrane cover) and land application of bio-solids.