Floating Aerators IrelandFloating aerator questions
Short answers to the questions people ask most before choosing a floating aerator: depth, sizing, installation, hire, licences, winter running and how to buy.
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Frequently asked questions
What is a floating aerator?
A floating aerator is a motor driven unit that sits on the surface of a lagoon, basin or pond. It churns the surface or throws water into the air so oxygen dissolves into it. That oxygen feeds the bacteria that break down organic pollution and keeps solids from settling.
What water depth does a floating aerator need?
Floating surface aerators work best in water 1.0 to 4.0 m deep. They can run well in basins up to 4.5 to 5.0 m, and deeper basins need a modified unit such as one with a draft tube. Small pond units run in about 0.5 to 0.8 m.
Do you have to drain the lagoon to install one?
No. Floating aerators go into a live basin and are held by three or four cables to posts or anchors on the bank. They rise and fall with the level, and can be moved later by small boat to reach dead zones.
How many kW does a lagoon need?
It depends on the oxygen demand and on how well the basin must be mixed. As a rough guide, partial mix lagoons need about 1 to 2 W per m3 and complete mix lagoons about 5 to 8 W per m3. We size every job from your load and basin, and show the working.
How much oxygen does a surface aerator add per kWh?
Manufacturers quote about 1.2 to 2.4 kg of oxygen per kWh in clean water tests. In real wastewater the figure is usually 50 to 70 percent of that, which is why sizing uses field values.
High speed or low speed surface aerator?
High speed floating units are direct drive, cost less and suit lagoons whose level changes. Low speed units turn a large turbine through a gearbox, move more water per kW and suit deep activated sludge tanks and oxidation ditches.
Can I hire an aerator in an emergency?
Yes. Hire units are used when blowers fail, during plant upgrades, for seasonal peaks and to save fish in lakes and reservoirs. Send an enquiry with the basin size and how soon you need cover.
What happens to floating aerators in frost?
Running aerators usually keep an area of open water. In long frosts the spray can ice floats and nearby walkways, so timers, a de-icing setting or a short shutdown are used.
Do I need a licence to discharge treated wastewater in Ireland?
Yes. Public sewer discharges are authorised by the EPA under the Waste Water Discharge (Authorisation) Regulations 2007. Industrial sites discharge under an EPA industrial emissions or IPC licence, or a local authority Section 4 licence. Good aeration helps a plant meet the limits in its licence.
Do you sell online?
No. Every site is different, so we sell by enquiry. Send the basin size, depth and what goes into it, and we will come back with a proposal.