ELASTOX®-R tube air diffuserAn idea conquers the world

The ELASTOX®-R tube air diffuser introduced by GVA to the market in 1983 is one of the first membrane compressed air aeration systems. Its design advantages and positive properties in continuous operation have convinced our customers all over the world:

  • Extremely low buoyancy due to a floodable supporting tube
  • Simple and fast mounting to and removal from aeration grids
  • Also ideal in case of unfavorable basin dimensions
  • Low piping requirement thanks to individual air diffuser lengths and the ability to mount them in pairs

Design details and the materials used have been constantly optimized and refined, but the floodable support tube principle has stood the test of time.

Typical applications are:

  • Preservation aeration of waste water, e.g. in balancing tanks
  • Oxygenation of activation basins
  • Oxygenation to stabilize sludge
  • Aeration of rivers and lakes
  • Aeration of fish ponds
  • CO2 admission for neutralization

The outstanding advantages of the ELASTOX®-R tube air diffuser:

  • Micro-bubbling gassing, and therefore excellent oxygen utilization
  • Defined distance between pores prevents coalescence of air bubbles during the generation process. The elastic membrane ensures a high degree of unclogged operation, even in difficult application environments.
  • Due to an intermittent mode of operation, the application of modern process techniques (e. g. nitrification/denitrification) is also possible in existing facilities.
  • Additional energy is saved due to the adaptability of oxygen admission to all load conditions without having to take a minimum diffuser admission into account
  • Floodable support tubes reduce buoyancy effects caused by the air diffusers.

Air diffuser lengths for every application

Tube air diffusers are normally installed with aeration lengths of 750 or 1,000 mm in newly built aeration tanks. In conjunction with the retrofitting of existing sewage treatment plants, old tank structures with an unfavorable geometry (e. g. gutters) are refitted and converted to aeration tanks. In this case GVA offers various air diffuser lengths to achieve optimum distribution at the bottom, especially for area-type aeration systems.

All materials were selected so that excellent resistance to the chemical and biochemical influences expected to be found in biological waste water treatment is achieved. If required, the membranes can be easily replaced.

The membrane material is especially important for its resistance to ageing.

EPDM membrane with extremely low plasticizer content.

Plasticizer-free silicone membrane with very good resistance to chemicals and anti-adhesive surface properties.


A great many oxygen admission tests on existing facilities have confirmed that ELASTOX®-R tube air diffusers are leaders in micro-bubble aeration systems.

The low-buoyancy ELASTOX®-R tube air diffusers operate based on the floodable supporting tube principl