Problem: The Sidney (Ohio) Wastewater Treatment Plant receives substantial industrial wastewater. To meet current and future needs and protect the Great Miami River, the city undertook an upgrade to increase capacity to 7.5 mgd design and 14 mgd peak, along with conversion from chlorine to UV disinfection. The plant must maintain at least 6 mg/L dissolved oxygen in the effluent. However, the UV system eliminated the pressure head needed for the cascade aeration system.
Solution: The Hazen design firm recommended a venturi aeration system from Mazzei Injector Company. The system uses a pump to recirculate water through a venturi injector, creating a vacuum that draws in ambient air. The air-water mixture is then discharged back into the basin. Two parallel venturi aeration systems to provide redundancy and turn-down capability, with injectors mounted above the water level.
Result: The system fits entirely within the basin boundaries and enables the plant to meet permit without increasing staff responsibilities. After nearly five years, plant personnel noted that annual oil replacement in the pump is the only routine maintenance required. These enhancements positioned the plant to support local growth while maintaining permit compliance.
661-363-6500; www.mazzei.net
