Extended aeration wastewater treatment

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Our extended aeration wastewater treatment system is a compact solution for projects serving 50 to 250 people. It is ideal for flow rates up to 150 m3/day.

What is an extended aeration wastewater treatment system?

The Rewatec extended aeration system uses activated sludge to treat wastewater in a single tank with two chambers. The first chamber is the biological reactor and the second chamber is the clarifier.

Our technology is the solution of choice for small community and commercial projects that strive for high performance with minimal energy consumption.

Installation of a prolonged aeration system

The system removes pollutants through a continuous aeration and clarification process, then returns effluent to the environment in accordance with local requirements.

When versatility matters, we have you covered. The Rewatec extended aeration system can serve 50 to 250 people and is ideal for flow rates up to 150 m3/day.

Where are our extended aeration systems used?

The Rewatec extended aeration wastewater treatment system is most often a solution for:

  • small communities
  • commercial areas
  • apartment buildings
  • office buildings
  • schools
  • golf courses

How do our extended aeration wastewater treatment systems work?

Sketch of an extended aeration compact system for the treatment of wastewater


Our extended aeration wastewater treatment system is simple, compact, and easy to operate. A single panel controls the operation of the system’s electromechanical equipment and can be adjusted as needed.

Fine screen

For projects serving more than 50 people, we recommend installing a fine screen upstream from the extended aeration tank. This screen provides a simple barrier that removes solids from wastewater and prevents them from entering the system's reactor.


Wastewater enters the extended aeration tank's first chamber, where membrane diffusers are fed by side-channel blowers. This aeration system injects fine air bubbles that break down solids and provide oxygen to bacteria and other microorganisms that feed on organic pollutants.


After passing through the reactor, wastewater flows via gravity into the extended aeration tank's clarification chamber. Suspended solids sink to the bottom of the tank and clarified effluent exits through an overflow outlet.

The bottom of the clarification chamber has a submerged pump that recirculates settled sludge back to the reactor. This process optimizes activated sludge concentrations, which maximizes the system's overall efficiency.

Extended aeration system maintenance

Protect your investment in your extended aeration wastewater treatment system — and maximize its service life — by having it regularly inspected and maintained.

If you want to check the condition of your system, feel free to contact our team.

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