WEEDLESS agitatorsFor all plant designs for municipal and industrial waste water

Agitators for waste water treatment facilities function according to a simple basic principle, but are important to the success and continuity of the overall process.

For this reason, great demands are justifiably placed on their performance and durability. The WEEDLESS agitators from GVA were specially developed to meet the high demands resulting from continuous operation, the corresponding operating conditions, and the often widely varied composition of municipal and industrial waste water.

Typical applications of WEEDLESS agitators are:

  • Mixing of anaerobic und anoxic zones for biological phosphate elimination and denitrification
  • Application in mixing and compensating basins
  • Compressed air aeration with separate circulation

WEEDLESS agitators operate successfully worldwide
GVA agitators have proven their high quality every day in hundreds of waste water treatment plants all over the world. As a specialist for these technologies, GVA delivers not only components and process know-how, but our business operations also include plant planning and consultation for plant operators all over the world.

WEEDLESS agitators – Always the right technological concept for every purification process
For over 20 years, GVA has been supplying high-quality system technology and components with our extensive know-how in waste water treatment plants. The continuity and success of the purification process depend mainly on a constant circulation and gentle mixing of the medium. The large-scale, slow running WEEDLESS agitators from GVA are designed to achieve maximum circulation and are available in a horizontal or vertical version:

  • WEEDLESS-T submerged agitators move the water horizontally.
  • WEEDLESS-V vertical agitators initiate a primarily vertical circulation in which the water is generally drawn up from the bottom of the basin to the surface of the water.
  • WEEDLESS-S floating vertical agitators are ideal for applications in which the water level varies.

Two or three blades
All agitator models are available with two-blade or three-blade propellers so that you can be sure you have the optimum component for the circulation process in each basin. The setting angle of the blades can be adjusted from 30° to 45° in 5° increments.

Any drive can be used
There is a wide range of standard drives for the various WEEDLESS models, and if necessary, different drive units can be used, for example with pole-changing motors or in combination with a frequency converter. Depending on the design, the volumetric capacity of the agitators is from 1.0 to 7.5 m3 of water per second.

Utilize the experience GVA has gained from hundreds of plants
The fact that all aspects of the plant layout and process technologies need to be considered is demonstrated again and again when determining where to place the agitators.


While designing the WEEDLESS-T submerged agitator, special requirements were put on the mounts and the gearbox.

WEEDLESS-V agitators consist of a geared motor above the water level and a propeller hanging below it.

Ideal when the water level varies: the WEEDLESS-S vertical agitator