Aeration technology brings wastewater up to code
The LeSourdsville Regional Water Reclamation Facility in Butler County, Ohio, was faced with a predicament: What could be done about floodwaters that compromised the plant’s cascade basin? Fortunately, a solution was found, and it utilized Mazzei technology.
The LeSourdsville facility was required to meet its National Pollutant Discharge Elimination System (NPDES) permit requirement of 6 mg/L dissolved oxygen at its Miami River outfall. During normal operation, the dissolved oxygen increase is accomplished in a cascade basin. However, during storm events, the river can rise to levels that completely flood the basin, rendering it useless.
The Mazzei AirJection system was chosen by plant administrators to battle this problem. Due to the confined space in the cascade basin and limited access to the site, a modular drop-in design incorporating a vertical turbine pump, the Mazzei Model 12050 Venturi injector and the Mazzei MTM nozzle manifold was adopted.
The aeration system was designed to provide oxygen transfer sufficient to raise the dissolved oxygen of the plant outfall from 3.5 mg/L to 5.6 mg/L under storm event plant flow conditions up to 26 million gal per day.
This provides the facility with a quiet, efficient, reliable back-up emergency aeration system that allows the plant to meet NPDES outfall dissolved oxygen requirements. During a storm event in 2004, the river rose and flooded the cascade basin. The Mazzei post-aeration system maintained the outfall at compliance levels of 5.6 mg/L at flows up to 31 mgd—20% higher than the aeration system’s peak design flow.