Gepeif is an economic interest group composed of Rhodia Organique St-Fons (phenol by-products), Rhodia PI Belle Etoile (manufacturer of Nylon intermediates) and Ciba Spécialités Chimiques St-Fons (dyes and pigments).

The Gepeif facility use biological treatment methods to process wastewater from the workshops of these three plants. The treatment capacity is 3,500 m³ per day for a pollution load equivalent to 400,000 equivalent reisdential units.

Gepeif was looking for a partner to take over the operation and maintenance of the treatment plant, improve the performance of the existing facilities and reduce operating costs.

The client also wanted to make its sludge treatment line more reliable.

To meet the needs of Gepeif, Veolia Water took over the management of the wastewater treatment plant and performs now the following functions :

• operation and maintenance of the wastewater treatment plant, including the supply of utilities (energy, reagents for the treatment process)
• sludge treatment : incineration on fluidised bed at the wastewater municipal treatment plant in Lyon

To improve the performance of the plants Veolia Water agreed to undertake pilot tests on Total Suspended Solids removal with :

• Actiflo™ tertiary treatment process for a volume of 100 m³ per hour over a period of 4 months (modular solution). Conclusive tests reducing TSS to 2-3 mg/L,
• Another process selected by Gepeif (flotation or lamellar settling process or chemical treatment process developed by Ciba).