Project: Murfreesboro Wastewater Treatment Plant
Location: Murfreesboro, Tennessee
Client: City of Murfreesboro
Solution: Wastewater Treatment
Technology: Aeration Basin with one 40-horsepower Hurricane Submersible Aerator
Wastewater treatment systems discharging directly to surface bodies of water typically require a post-aeration system before the water is released. During the post-aeration process, air is introduced to the water to raise the dissolved oxygen (DO) level of the water to a standard level to minimize the occurrence of low DO levels in the water basins, which can have negative effects on wildlife.
The City of Murfreesboro, Tennessee, chose a 40-horsepower Hurricane Aerator for installation in a 19-foot-deep post-aeration basin. The Hurricane provides a combined pattern of fine bubble aeration and spiral mixing. This combination achieves reliable oxygen transfer throughout the square 45-foot tank for the daily flows of 13-19 million gallons, bringing the treated effluent to state standards (DO >6.0 mg/L) before discharge.
The Hurricane aerator is a freestanding unit, which is very easy to install because it does not require anchoring or bolting. The 360-degree, radially mixing system uses air diffusers designed for high oxygenation efficiency and mixing over a wide area. Multiple diffuser lengths can be adjusted for any basin shape to maximize mixing efficiency.
Principle of Operation
The Hurricane self-aspirating aerator is designed for submerged operation and utilizes a chemical-duty, explosion-proof, water-cooled motor. The motor shaft spins the impeller (the only moving part), which creates a low-pressure zone and pulls air from above the water surface. Air and water are efficiently mixed and the air is broken into fine bubbles by the spinning impeller. The turbulence and flow created by the impeller disperse the air and water mixture through diffuser pipes. The fine air bubbles rise and efficiently mix the water above and around the unit, creating mixing throughout the basin.
Hurricane Submersible Aerator/Mixer Features
- Available in 304 or 316 (optional) stainless steel configuration to prevent corrosion, even in the harshest environments
- Stainless steel air intake pipe will not deteriorate from exposure to UV rays
- Hardened 17-4 stainless steel impeller machined from a single piece of steel for added durability against solids
- Five- to 100-horsepower (3.75 kW-75 kW) units are available
- Can be operated as an aerator/mixer or as just a mixer
- Multiple diffuser lengths can be adjusted for any basin shape to maximize mixing efficiency
Easy Installation and Low Maintenance
- Freestanding unit means no anchoring is required
- Adjustable legs allow easy leveling of the unit on most basin floors without additional level pad
- Aerobic digesters
- Sequencing batch reactors (SBR)
- Post-aeration basins
- Sludge holding tanks
- Flow equalization basins
- Deep-tank applications with small-surface areas