Filtralite® Clean, an exclusive material for wastewater fixed bed technology

The biofilters, in use at Annecy´s wastewater treatment plant (SILA), have been filled with Filtralite (initially implemented under the name Biolite® in the Suez-patented BIOFOR®), offering optimum conditions for biofilm growth in the biological treatment of wastewater.

Lightweight and porous, Filtralite® Clean, made of particles of expanded clay, features angular and sharp faces and a high specific contact area. These properties facilitate an efficient bacteria development for BOD (Biochemical Oxygen demand) removal, TSS (Total Suspended Solids) removal and nitrification process.


Filtralite®, a solution easy to implement

The Annecy Wastewater treatment association (SILA) awarded Quadrimex Chemical the contract to drain, refill and replace the filtration media of 3 biological filters in the SILOE plant (230 000 population equivalent).

Quadrimex Chemical managed to renew the filter media of 3 biological filters in only 12 weeks. The company developed an innovating pumping system (based on Venturi effect), non-polluting and noiseless. This system is made to drain the biological filter in order to insure the maintenance of the equipments.

Three biological filters had to be drained for maintenance : 2 filters N (Nitrogen) and 1 filter C (Carbon).

Thereafter, the equipments were refilled with :

  • the re-use of the same filtration media recovered from the draining,
  • and new Filtralite Clean media.