The city of Colorado Springs in Colorado currently operates a 65 mgd wastewater treatment facility. To help meet the stringent water quality standards for denitrification, the facility has employed 20 7.5 hp AquaDDM mixers instead of installing submerged directional mixers.
Four AquaDDM mixers are used in each of five anoxic basins to partition anoxic zones into four compartments. Utilizing the mixers in this manner accomplishes mixing of the influent and provides a completely mixed environment (every constituent in the reactor exists at a uniform concentration at every point in the reactor) necessary for successful denitrification, without aeration. The need for tank baffles in the anoxic zones is eliminated due to the AquaDDM mixer’s integrated flow vanes and lower input torque.
The mixers are equipped with a pivotal mooring arm to provide ease of maintenance for the plant operators. Located on the walkway at each quadrant of the anoxic basin are recessed ports with removable cross section grating. Operators can remove the grating and use the attached mooring cable to pull the mixers to the port. They can then attach a winch to the lifting harness on the mixer motor. This arrangement provides total support during routine maintenance of the mixer without removing it from the basin.
A few years ago, the plant also replaced 30 submerged units that were being used in its primary effluent channel with three 3 hp AquaDDM mixers with directional elbows and one AquaDDM mixer without an elbow. Since replacing these submerged units, the plant has saved significant costs on power, labor and maintenance.
Download the full case study to learn more
Download Case Study
