Aqua Aerobic Systems – MixAir is a biological system that allows a single aeration basin to be used since its aeration and mixing is accessible above the water surface. Cyclically operated aeration and mixing promote anoxic/aerobic and anaerobic environments with low energy consumption without having separate anoxic/anaerobic tanks and mixers to provide a 3 Stage Bardenpho-type process.
The system features “Retrievable Diffusers” in racks that can be lifted by a davit crane and rotated outside the basin or other aeration devices. Mixing is provided by proven AquaDDM® Direct Drive floating mixers. This concept allows for fewer aeration basins initially since the facility can have a single aeration basin and add basins with growth. MixAir systems can accommodate low cost construction of a round basin with movable forms or other configuration needed.
Installations include Little Blue Valley Sewer District (LBVSD) Middle Big Creek WWTP in Pleasant Hill, Missouri, and Fishing River WWTP and Rocky Branch WWTP in Kansas City, Missouri.
Energy Savings of Separating Mixing and Air
The following chart demonstrates the relative cost savings that can be realized by using the MixAir system in biological reactor. When comparing a life cycle cost analysis, whether with diffused aeration or surface aeration, the use of the MixAir system can lead to the best option to match the actual conditions. Example: a 200 blower HP required with diffusers alone for mixing, must run all the time, where only 115 blower HP required for air for oxygen at design loading. With a 25 HP mixer, only need to provide 140 total HP to mix and aerate (lower blower capitol $, lower power consumption at design load).
When factoring additional power savings related to lower than design organic loadings during much of plant life, as is typical, total savings can be quite considerable.
Little Blue Valley Sewer District (LBVSD) Middle Big Creek WWTP in Pleasant Hill, MO
Designed by HDR Engineers and constructed by Kat Excavation in 2013. A single, 125 ft diameter aeration basin with retreivable diffusers and 3 AquaDDM® Direct Drive floating mixers. The control system optimized pollutant and nutrient removal and minimize energy requirements by controlling system through a PLC-based system. The system continuously monitors and controls the dissolved oxygen level and incorporates adjustable Nitrification and Denitrification cycles. The project included Qty 3- 125 HP blowers each designed for 1750 SCFM at 10 psi and two 75 ft diameter, 14 ft SWD Final Clarifiers.
Rocky Branch WWTP in Kansas City, Missouri
Designed by HDR Engineers and constructed by Huffman Construction in 2002. A single basin aeration basin with retrievable diffusers and AquaDDM® Direct Drive floating mixers.
Fishing River WWTP in Kansas City, Missouri
Designed by Burns & McDonnell Engineers and constructed by Foley Construction and started up in April of 2013. The biological system was composed of two 120 ft diameter aeration basins with Retrievable Diffusers and Qty 1-60 HP AquaDDM® Direct Drive mixers. The project included Qty 5- 100 HP blowers each designed for 1500 SCFM at 9.5 psi and two 65 ft diameter, 14 ft SWD Final Clarifiers.
Sedalia, MO; Central Wastewater Treatment Plant
Designed by HDR Engineers and constructed by Huffman Construction. A single basin aeration basin with retrievable diffusers and AquaDDM® Direct Drive floating mixers.
The system features fine-bubble “Retrievable Diffusers” in racks that can be lifted by a davit crane and rotated outside the basin for maintenance or replacement without taking the aerations system offline.
Available Membrane Materials:
EPDM, Silicone, and others upon request
Membrane lengths from 1 foot to 8 feet (30.5 to 244 cm) per diffuser
From 0.6 to 6.0 SCFM per foot of length (3.3 to 33.0 m3/hr per meter of length)
Standard oxygen transfer efficiency from 1.5% to over 2.0% per foot of submergence*