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Compact unit for biological treatment of wastewater using granular activated sludge.

GRASS® allows the production of stable granular activated sludge in biological tanks of any shape. GRASS® is therefore suitable for new plant construction as well as for revamping.

Curious to know more? Read on!

What are "granules"?

The granules are aggregates of bacteria with high purifying performances that agglomerate to form “beads” whose settling speed is much higher than the classical flocs of an activated sludge.

How are GRASS® granules obtained?

The granules GRASS® are selected and their growth is promoted by modifying the classical phases of an SBR. No reagents or seeding with an existing granular slurry is required.

Who the technology is for GRASS® ?

Initially designed for effluents from the food industry, it is also very well suited for effluents from the wood industry as well as the return juices from anaerobic digesters, but also for normally concentrated urban water.

What are the interests of the GRASS® technology ?

We offer GRASS® technology to customers who want to optimize the operation and operating costs of their biological treatment plant.

Indeed, the technology GRASS® allows to :

  • increase the treatment capacity of a wastewater treatment plant
  • increase the removal of certain pollutants (N and P)
  • eradicate filamentous bacteria and considerably increase the settling speed of the biology.

The process also makes water treatment less energy intensive. A 30% reduction of your energy consumption is possible!

In summary:

GRASS® technology secures the performance of a traditional SBR and provides significant savings on capital (CAPEX) and operating (OPEX) costs. With this technology, our customers can :

Discover GRASS® at


How do you know if GRASS® technology will work for you?

To know if you can easily develop a granular biology on your effluent, we can carry out a diagnosis of the latter. We realize 4 types of them:

SILVER Version

Silver = Effluent characterization

GOLD version

Gold = SILVER + biodegradability test


Platinium = GOLD + pilot test in
laboratory for 2 to 3 months

DIAMOND version

Diamond = GOLD + pilot test on site with a container for 4 to 6 months