Jet aeration systems for wastewater treatment plants

Looking for an aeration technique for deep basins in wastewater treatment? Jet aeration is suitable for basins over 5 meters deep. This unique, innovative and highly efficient jet aeration system is used worldwide in various industrial sectors (food, paper, chemicals, waste processing, etc.).

Mixing and aeration of waste water

In jet aeration, air is mixed with a liquid and injected into the wastewater. This forms a powerful water plume with high turbulence.

There are two major differences compared to traditional systems: the height of the installed system and the position of the aeration nozzles.

Jet aeration in wastewater treatment plants

Height and position of the nozzles

The current jet aeration system is designed to be elevated, typically 75 cm to 120 cm above the basin floor. Certainly, this elevation proves to be cost effective, as less power is required for the blowers.

Secondly, the jet aeration nozzles are not positioned horizontally, as in traditional systems. The nozzles are positioned at a downward angle, depending on the shape of the basin. This results in a higher efficiency.

Typical jet aeration system

A typical installation is consisting of aerators, piping in the aeration basin, backwash system, dry mounted centrifugal pump and roots blowers. Connecting piping and the supporting fastening system for the jet aerator are made of stainless steel. Two types of jet aeration systems are available: traditional systems and systems with slot injector.

Traditional jet aeration systems

The aerator itself consists of two nozzles. Injection fluid – recirculated fluid/air mixture – is sprayed from an inner nozzle into an outer mixing nozzle, where compressed atmospheric air is added. This creates very fine bubbles. As a result, a large interface between air and wastewater is provided, leading to a very high oxygen transfer coefficient.

Jet Aeration with Slot Injector

The Slot Injector system is similar to a modern jet aeration system, but has a higher efficiency. Its unique shape provides a high percentage of dissolved air and a superior mass transfer coefficient. In addition, the mixing chamber of the jet aerator includes a pressure recovery zone, which is lacking in traditional systems.

traditional injector of jet aeration
slot injector type of jet aeration

Backwash system

Easy backwashing by reverting the flow through the inner nozzle, removing all dirt and debris from the system.

What are the advantages of a jet aeration system?

  • High efficiency in oxygen transfer and mixing capacity
  • Maintenance friendly
  • No moving parts in the aeration basin
  • Insensitive to clogging
  • little foaming
  • Very suitable for use in deep aeration basins
  • Low installation, energy and maintenance costs
  • Low operating costs
  • Long-term and stable efficiency 
  • Durable: life span of more than 20 years
  • No aerosols
  • No pre-cooling of the aeration fluid required
  • Not sensitive to frost
  • Limited waste gas volume
  • Superior corrosion and wear resistance 


Where can jet aeration be used?

Jet aeration technology is applicable to a wide range of water treatment applications and sludge treatment, such as biological water treatment, activated sludge aeration, aerobic sludge stabilization, SBR (sequencing batch reactor), MBR (membrane bioreactor), aerobic digestion, etc. Jet aeration is used in both industrial and community water treatment. The Slot Injector™ aeration system with injection slots is specifically suitable for industrial-scale biological wastewater treatment applications.

Optimization of existing installations

In the context of a production expansion and/or an optimization of the energy consumption, Task can assist you. Moreover, most types of (jet) aerators can be equipped with the Slot Injector™ system.

This way, a higher oxygen transfer can be obtained, without having to replace the existing compressed air supply. On the other hand Slot Injectors also allow to achieve the same oxygen level with a smaller air flow. The jet aeration system with Slot Injectors also provides a more dispersed operating range at peak loads, without compromising the mixing process.

We review the specifications of your existing aeration system with pleasure for possible retrofitting with the Slot Injector™ system. Do not hesitate to contact us!

Other types of aerators available

In addition to the submersible aerators, we also offer surface aerators:

  • Fixed surface aerators
  • Lowspeed floating surface aerators.

For more information, please contact us.