Anoxic Mixing Energy Savings

PHi mixing in anoxic basins results in a significant energy savings over mechanical mixers!

The Department of Environmental Protection for New York City commissioned a study of PHi’s mixing in a BNR basin at the city’s Red Hook WPCP during 2005 and 2006. The study results showed that the PHi mixing system was significantly less expensive when compared to the existing submersible mechanical mixers in capital costs, maintenance costs, and energy usage.

Following is a summary of the test results:

  • Both mixers achieved distribution of suspended solids throughout the bulk volume of the anoxic zones.
  • Initial capital cost is higher for the Davis EMU mixers than the PHi Mixing System. Additionally, due to lower preventive maintenance and energy costs, the PHi Mixing System has a lower capitalized cost.
  • Over a 10 year period, the savings in capitalized costs using the PHi Mixing System would be lower based on vendor’s own recommendations.
  • Experience at the Red Hook WPCP suggests that the Davis EMU Uni-Prop mixers are prone to frequent breakdowns.

Download the NYC Red Hook Report (PDF)

DO Enhancement in Aeration Basin Energy Savings

PHi mixing in conjunction with fine bubble diffuser aeration results in energy savings.

PHi conducted a test at GSEE, in LaVergne, TN, where the PHi mixing system was operated at the same time as a fine bubble diffuser system.  The results of the test show that the energy consumption required to reach the oxygen saturation point  was reduced.

The reason the aeration is enhanced is due to the down force motion created by the PHi mixing system, which keeps the fine bubbles in contact with the liquid longer, allowing for more oxygen transfer.  In the video “Aeration Enhancement” you can see that some of the fine bubbles go down, not up, which is the result of the PHi mixing.

 Download the complete GSEE report (PDF)

Aeration Enhancement Video