Biological treatments are mainly used to eliminate soluble material. For biological treatments, NANTAISE DES EAUX INGÉNIERIE uses a lot of process :

Suspended growth

• Activated sludge (traditional or SBR)
  
  • Surface aerators
  • Submersible aerators
  • Fine bubbles air diffusors

Attached growth

• Rotating biological contactors (RBC)
• Bacteria beds

Separation of phases by decantation, flotation, membranes bioreactor (MBR)