SURFACE AERATOR SPACING

[allie075]

Hi guys,

Anyone experienced with surface aerators for aerated lagoons? How do you space them?

I've heard that they should be placed at the corners and middle to prevent dead zones but Mara has warned against spacing them too close because the eddy interference leads to reduced oxygen transfer.

A spacing of 20 meters was recommended for 100hp aerators but most of our applications are smaller than that.

Any idea where I'd find appropriate spacing information? Are there, for instance, influence diagrams for aerators showing a radius of influence?

Regards,
Allie

 

[bimr]

Biological Wastewater Treatment by Grady has some design guidelines.

100 HP mixers closer than 30 meters may give you interactions. However, draft tubes should allow that distance to be reduced.

You probably need 30-50 HP/ Million Gallons to maintain the solids in suspension.

The effective distance of an aerator is typically 2 ft/HP with a maximum separation of 250 feet. If the bain depth is greater than 3 meters, draft tubes should be used.

If you have multipe basins, an economical volume split is 0.6:0.2:0.2.

 

[Watthour]

How deep is the lagoon (on average)?